Featured Papers


Parvovirus B19-Induced Severe Anemia in Heart Transplant Recipients: Case Report and Review of the Literature.
Clinical transplantation
Pinto, N. C., Newman, C., Gomez, C. A., Khush, K. K., Moayedi, Y., Lee, R., Teuteberg, J. J., Montoya, J. G.
2019: e13498

Abstract »
We report a case of a 64-year-old woman who developed transfusion-dependent anemia after cardiac transplantation, the etiology of which was unknown after initial comprehensive evaluation. At the suggestion of the Transplant Infectious Diseases consultant, microbial agents with red blood cell tropism pertinent to this patient such as Parvovirus B 19 (B19V) were investigated. The B19V viral load by PCR in peripheral blood was >100,000,000 copies/ml and after treatment with intravenous immunoglobulin (IVIG), her anemia resolved. Here, we summarize the clinical and virologic characteristics, treatment, and outcome of fifteen cases of B19V-induced anemia in heart transplant recipients. Spontaneous recovery from anemia secondary to B19V has also been reported in some heart transplant recipients, possibly due to an absence of their B19V P-antigen receptor and/or reduction of their immunosuppression. Therefore, in heart transplant patients, B19V should be suspected early as a cause of severe anemia of unknown etiology. The extent that B19V-induced anemia is underdiagnosed in heart transplant recipients is unknown. This article is protected by copyright. All rights reserved.

Plasmonic gold chips for the diagnosis of Toxoplasma gondii, CMV, and rubella infections using saliva with serum detection precision. 
European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology
Li, X., Pomares, C., Peyron, F., Press, C. J., Ramirez, R., Geraldine, G., Cannavo, I., Chapey, E., Levigne, P., Wallon, M., Montoya, J. G., Dai, H.

Abstract »
Sampling the blood compartment by an invasive procedure such as phlebotomy is the most common approach used for diagnostic purposes. However, phlebotomy has several drawbacks including pain, vasovagal reactions, and anxiety. Therefore, alternative approaches should be tested to minimize patient's discomfort. Saliva is a reasonable compartment; when obtained, it generates little or no anxiety. We setup a multiplexed serology assay for detection of Toxoplasma gondii IgG and IgM, rubella IgG, and CMV IgG, in serum, whole blood, and saliva using novel plasmonic gold (pGOLD) chips. pGOLD test results in serum, whole blood, and saliva were compared with commercial kits test results in serum. One hundred twenty serum/saliva sets (Lyon) and 28 serum/whole blood/saliva sets (Nice) from France were tested. In serum and whole blood, sensitivity and specificity of multiplex T. gondii, CMV, and rubella IgG were 100% in pGOLD when compared to commercial test results in serum. In saliva, sensitivity and specificity for T. gondii and rubella IgG were 100%, and for CMV IgG, sensitivity and specificity were 92.9% and 100%, respectively, when compared to commercial test results in serum. We were also able to detect T. gondii IgM in saliva with sensitivity and specificity of 100% and 95.4%, respectively, when compared to serum test results. Serological testing by multiplex pGOLD assay for T. gondii, rubella, and CMV in saliva is reliable and likely to be more acceptable for systematic screening of pregnant women, newborn, and immunocompromised patients.

Toxoplasmose congenitale aux Etats-Unis: observations cliniques et serologiques chez les nourrissons nes de meres traitees pendant la grossesse. 
Parasite (Paris, France)
Olariu, T. R., Press, C., Talucod, J., Olson, K., Montoya, J. G.
2019; 26: 13

Abstract »
We assessed clinical and serologic findings in 25 infants with congenital toxoplasmosis born to mothers treated during pregnancy in the United States. Results indicate a lower prevalence of eye findings and hydrocephalus in the group of infants born to treated mothers (62.5% and 38.5%, respectively) compared to results on the same pathologies reported in our previous cohort of infants born to untreated mothers (92.2% and 67.7%, respectively). The sensitivity of the IgM ISAGA and IgA ELISA in the present study were lower (44% and 60%, respectively) compared to sensitivity of these methods in our previously studied group of infants born to untreated mothers (86.6% and 76.5%, respectively). These findings provide further evidence that anti-parasitic treatment if administered during pregnancy can contribute to better clinical outcomes, even in countries where systematic screening and treatment have not been routinely implemented.

Role of Toxoplasma IgA as part of a Reference Panel for the Diagnosis of Acute Toxoplasmosis During Pregnancy. 
Journal of clinical microbiology
Olariu, T. R., Blackburn, B. G., Press, C., Talucod, J., Remington, J. S., Montoya, J. G.

Abstract »
This study evaluated the usefulness of adding the Toxoplasma gondii IgA antibody ELISA test to the serologic panel of tests done for the diagnosis of acute toxoplasmosis in pregnant women in a reference laboratory in the United States. We conducted a retrospective study of 690 consecutive pregnant women with positive T. gondii IgG antibody test results who also had T. gondii IgA and IgM antibody tests performed. Patients were defined as acutely or chronically infected with T. gondii based on a panel of serologic tests performed at the Palo Alto Medical Foundation - Toxoplasma Serology Laboratory (PAMF-TSL). Among the 81 women who were positive by T. gondii IgA antibody ELISA testing, 61 (75.3%) were acutely infected with T. gondii, while of the 547 who were negative by IgA testing, only 24 (4.4%) were acutely infected (p<0.001). Among the 71 women who were positive by both IgA and IgM antibody tests, 61 (85.9%) were acutely infected, compared to 24 (19.2%) of the 125 women who were positive by only the IgM ELISA (p<0.001). These results demonstrate that pregnant women with T. gondii IgA antibodies are more likely to have had a recent infection with T. gondii compared to pregnant women without T. gondii IgA antibodies. Toxoplasma IgA antibody testing can therefore improve the accuracy of a serologic panel for the diagnosis of acute toxoplasmosis during pregnancy. Physicians who ordered testing only for T. gondii IgG and IgM should also request additional testing for IgA and IgG avidity, if both IgG and IgM are positive. This further testing should be ideally performed in a reference laboratory.

Systematic screening and treatment of toxoplasmosis during pregnancy: is the glass half full or half empty? 
American journal of obstetrics and gynecology
Montoya, J. G.
2018; 219 (4): 315–19

Editorial introductions 
Montoya, J. G., Perl, T. M.
2018; 31 (4)

Prevention and treatment of cytomegalovirus in immunocompromised patients: beyond DNA polymerase inhibition. 
Current opinion in infectious diseases
Montoya, J. G., Gomez, C. A., Lee, R.

Deconstructing post-exertional malaise in myalgic encephalomyelitis/ chronic fatigue syndrome: A patient-centered, cross-sectional survey. 
PloS one
Chu, L., Valencia, I. J., Garvert, D. W., Montoya, J. G.
2018; 13 (6): e0197811

Abstract »
BACKGROUND: Post-exertional malaise (PEM) is considered to be the hallmark characteristic of myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS). Yet, patients have rarely been asked in formal studies to describe their experience of PEM.OBJECTIVES: To describe symptoms associated with and the time course of PEM.METHODS: One hundred and fifty subjects, diagnosed via the 1994 Fukuda CFS criteria, completed a survey concerning 11 symptoms they could experience after exposure to two different types of triggers. We also inquired about onset and duration of PEM and included space for subjects to write in any additional symptoms. Results were summarized with descriptive statistics; McNemar's, paired t-, Fisher's exact and chi-square goodness-of-fit tests were used to assess for statistical significance. RESULTS: One hundred and twenty-nine subjects (90%) experienced PEM with both physical and cognitive exertion and emotional distress. Almost all were affected by exertion but 14 (10%) reported no effect with emotion. Fatigue was the most commonly exacerbated symptom but cognitive difficulties, sleep disturbances, headaches, muscle pain, and flu-like feelings were cited by over 30% of subjects. Sixty percent of subjects experienced at least one inflammatory/ immune-related symptom. Subjects also cited gastrointestinal, orthostatic, mood-related, neurologic and other symptoms. Exertion precipitated significantly more symptoms than emotional distress (7±2.8 vs. 5±3.3 symptoms (median, standard deviation), p<0.001). Onset and duration of PEM varied for most subjects. However, 11% reported a consistent post-trigger delay of at least 24 hours before onset and 84% endure PEM for 24 hours or more. CONCLUSIONS: This study provides exact symptom and time patterns for PEM that is generated in the course of patients' lives. PEM involves exacerbation of multiple, atypical symptoms, is occasionally delayed, and persists for extended periods. Highlighting these characteristics may improve diagnosis of ME/CFS. Incorporating them into the design of future research will accelerate our understanding of ME/CFS.

Toxoplasmosis in the non-orthotopic heart transplant recipient population, how common is it? Any indication for prophylaxis? 
Current opinion in organ transplantation
Dhakal, R., Gajurel, K., Montoya, J. G.
2018; 23 (4): 407–16

Abstract »
Unlike in orthotopic heart transplant (OHT) setting where toxoplasma prophylaxis is a standard practice in pretransplant toxoplasma seronegative recipients who have received donor hearts from seropositive donors (D+/R-), there is no consensus regarding prophylaxis in non-OHT recipients. The incidence of toxoplasma disease in non-OHT recipients is less than 1% but its true burden is underestimated. Among 31 cases of toxoplasma disease reported from 2004 through 2017, renal and liver transplant recipients comprised of 90% of cases. A total of 94% of 18 recipients with known pretransplant serology were seronegative recipients (mostly D+/R-). Out of 16 recipients with adequate information, 10 (63%) and five (31%) were deemed to be donor derived and nondonor-derived primary toxoplasmosis respectively. Tissue invasive reactivation was uncommon. Almost all cases were described in patients not on prophylaxis at the time of presentation. Universal screening of donor/recipient toxoplasma serology for risk stratification is beneficial as illustrated by reports of fatal cases of toxoplasmosis due to unavailability of positive donor serology results. Toxoplasma disease in non-OHT predominantly occurs in pretransplant seronegative recipients- mostly in D+/R- group and is rare in seropositive recipients. Posttransplant prophylaxis should be targeted against the high-risk D+/R- group and should be considered in seropositive recipients in whom unusually high immunosuppression is implemented. Toxoplasma serologies and PCR should be used in combination for the diagnosis of toxoplasmosis in non-OHT patients.

Genetic characterization of Toxoplama gondii DNA samples isolated from humans living in North America: An unexpected high prevalence of atypical genotypes. 
The Journal of infectious diseases
Pomares, C., Devillard, S., Holmes, T. H., Olariu, T. R., Press, C. J., Ramirez, R., Talucod, J., Estran, R., Su, C., Dubey, J. P., Ajzenberg, D., Montoya, J. G.

Abstract »
Whereas in Europe most of Toxoplasma gondii genotypes belong to the type II lineage, in Latin America, type II is rare and atypical strains predominate. In North America, data on T. gondii genotypes in humans are scarce.In this study, T. gondii DNA samples from 67 patients diagnosed with toxoplasmosis in the United States were available for genotyping. Discriminant analysis of principal components was used to infer each atypical genotype to a geographic area where patients were likely infected. Associations between genotype, disease severity, immune status, and geographic region, were also estimated.Forty-one DNA samples out of 67 were successfully genotyped: 18 (43.9%) and 5 (12.2%) were characterized as types II and III, respectively. The remaining 18 genotypes (43.9%) were atypical and were assigned to a geographic area. Ten genotypes originated from Latin America, 7 from North America and one from Asia (China). In North America, unlike Europe, T. gondii atypical genotypes are common in humans and unlike Latin America, type II strains are still present with significant frequency. Clinicians should be aware that atypical genotypes are common in North America and have been associated with severe ocular and systemic disease and unusual presentations of toxoplasmosis in immunocompetent patients.

Value of Circulating Cytokine Profiling During Submaximal Exercise Testing in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. 
Scientific reports
Moneghetti, K. J., Skhiri, M., Contrepois, K., Kobayashi, Y., Maecker, H., Davis, M., Snyder, M., Haddad, F., Montoya, J. G.
2018; 8 (1): 2779

Abstract »
Myalgic Encephalomyelitis or Chronic Fatigue Syndrome (ME/CFS) is a heterogeneous syndrome in which patients often experience severe fatigue and malaise following exertion. Immune and cardiovascular dysfunction have been postulated to play a role in the pathophysiology. We therefore, examined whether cytokine profiling or cardiovascular testing following exercise would differentiate patients with ME/CFS. Twenty-four ME/CFS patients were matched to 24 sedentary controls and underwent cardiovascular and circulating immune profiling. Cardiovascular analysis included echocardiography, cardiopulmonary exercise and endothelial function testing. Cytokine and growth factor profiles were analyzed using a 51-plex Luminex bead kit at baseline and 18 hours following exercise. Cardiac structure and exercise capacity were similar between groups. Sparse partial least square discriminant analyses of cytokine profiles 18 hours post exercise offered the most reliable discrimination between ME/CFS and controls (κ = 0.62(0.34,0.84)). The most discriminatory cytokines post exercise were CD40L, platelet activator inhibitor, interleukin 1-β, interferon-α and CXCL1. In conclusion, cytokine profiling following exercise may help differentiate patients with ME/CFS from sedentary controls.

Toxoplasma gondii Infection in the United States, 2011-2014 
AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENEJones, J. L., Kruszon-Moran, D., Elder, S., Rivera, H. N., Press, C., Montoya, J. G., McQuillan, G. M.
2018; 98 (2): 551–57

Abstract »
Toxoplasma gondii can cause severe neurologic and ocular disease when transmitted congenitally and in immunosuppressed persons. Sera collected in the National Health and Nutrition Examination Survey 2011 through 2014 in 13,507 persons ≥ 6 years old were tested for T. gondii immunoglobulin (Ig) G and IgM antibodies, and in those both IgG and IgM antibody positive, for IgG avidity. Overall, 11.14% (95% confidence limits [CL] 9.88%, 12.51%) were seropositive for T. gondii IgG antibody (age-adjusted seroprevalence 10.42% [95% CL 9.19%, 11.76%]); in women aged 15-44 years, the age-adjusted T. gondii IgG seroprevalence was 7.50% (95% CL 6.00%, 9.25%). In multivariable analysis, risk for IgG seropositivity increased with age and was higher in males; persons living below the poverty level; persons with ≤ a high school education compared with those with > a high school education; and non-Hispanic black, Mexican American, and foreign born non-Hispanic white persons compared with U.S.-born non-Hispanic white persons. Overall, 1.16% (95% CL 0.94%, 1.42%) were T. gondii IgM antibody positive and 0.71%, (95% CL 0.54%, 0.92%) were both IgM and IgG antibody positive. In multivariable analysis, the significant risk factors for being both IgM and IgG positive were older age, crowding, and non-U.S. birth origin compared with U.S.-born persons. Among those positive for both IgM and IgG antibody, almost all had high avidity (all women aged 15-44 years had high avidity). Toxoplasma gondii antibody prevalence remains relatively low in the United States, although it is higher in non-U.S.-born persons, males, and some minority and socioeconomically disadvantaged groups.

Toxoplasmosis in hematopoietic cell transplant recipients 
TRANSPLANT INFECTIOUS DISEASEGajurel, K., Dhakal, R., Montoya, J. G.
2017; 19 (5)

Validation of IgG, IgM multiplex plasmonic gold platform in French clinical cohorts for the serodiagnosis and follow-up of Toxoplasma gondii infection. 
Diagnostic microbiology and infectious disease
Pomares, C., Zhang, B., Arulkumar, S., Gonfrier, G., Marty, P., Zhao, S., Cheng, S., Tang, M., Dai, H., Montoya, J. G.
2017; 87 (3): 213-218

Abstract »
We report the use of the multiplexed T. gondii IgG, IgM test on plasmonic gold (pGOLD) platform in the setting of T. gondii infection by analyzing 244 sera from Nice, France (seroconversion, chronically infected, non-infected and newborns serum samples). Results were compared with commercial tests for the detection of IgG and IgM and their overall clinical final interpretation of a complete serological profile. The IgG and IgM test results on the platform were in agreement in, respectively, 95% and 93% with the commercial kits. When comparing with the overall clinical interpretation of the serological profile, the agreement reached 99.5% and 97.7% for IgG and IgM, respectively. This innovative pGOLD platform allows detection of both IgG and IgM simultaneously with only ~1 microliter of serum. The multiplexed IgG/IgM test on pGOLD platform is a strong candidate for its use in the massive screening programs for toxoplasmosis during pregnancy.

Congenital Toxoplasmosis in France and the United States: One Parasite, Two Diverging Approaches. 
PLoS neglected tropical diseases
Peyron, F., Mc Leod, R., Ajzenberg, D., Contopoulos-Ioannidis, D., Kieffer, F., Mandelbrot, L., Sibley, L. D., Pelloux, H., Villena, I., Wallon, M., Montoya, J.G.
2017; 11 (2)

Lifelong Persistence of Toxoplasma Cysts: A Questionable Dogma? 
Rougier, S., Montoya, J. G., Peyron, F.
2017; 33 (2): 93–101

Abstract »
It is believed that infection by Toxoplasma gondii triggers a lifelong protective immunity due to the persistence of parasitic cysts which induce immunoprotection against reinfection. A review of the scientific literature since the 1950s did not yield any definitive data regarding the duration of cysts in the host or the presence of lifelong protective immunity, which led us to question this dogma. We put forward the hypothesis that sustained immunity to T. gondii requires repeated antigenic stimulations. The decline of seroprevalence recently observed in many countries might contribute to explain the loss of immunity. We address the potential consequences of this phenomenon, should it persist and worsen.

Cytokine signature associated with disease severity in chronic fatigue syndrome patients.
Proceedings of the National Academy of Sciences of the United States of America
Montoya, J. G., Holmes, T. H., Anderson, J. N., Maecker, H. T., Rosenberg-Hasson, Y., Valencia, I. J., Chu, L., Younger, J. W., Tato, C. M., Davis, M. M.
2017; 114 (34): E7150–E7158

Abstract »
Although some signs of inflammation have been reported previously in patients with myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS), the data are limited and contradictory. High-throughput methods now allow us to interrogate the human immune system for multiple markers of inflammation at a scale that was not previously possible. To determine whether a signature of serum cytokines could be associated with ME/CFS and correlated with disease severity and fatigue duration, cytokines of 192 ME/CFS patients and 392 healthy controls were measured using a 51-multiplex array on a Luminex system. Each cytokine's preprocessed data were regressed on ME/CFS severity plus covariates for age, sex, race, and an assay property of newly discovered importance: nonspecific binding. On average, TGF-β was elevated (P = 0.0052) and resistin was lower (P = 0.0052) in patients compared with controls. Seventeen cytokines had a statistically significant upward linear trend that correlated with ME/CFS severity: CCL11 (Eotaxin-1), CXCL1 (GROα), CXCL10 (IP-10), IFN-γ, IL-4, IL-5, IL-7, IL-12p70, IL-13, IL-17F, leptin, G-CSF, GM-CSF, LIF, NGF, SCF, and TGF-α. Of the 17 cytokines that correlated with severity, 13 are proinflammatory, likely contributing to many of the symptoms experienced by patients and establishing a strong immune system component of the disease. Only CXCL9 (MIG) inversely correlated with fatigue duration.

Cytokine profiles in patients with toxoplasmic lymphadenitis in the setting of pregnancy.
Pomares, C., Holmes, T. H., Estran, R., Press, C. J., Ramirez, R., Talucod, J., Maecker, H., Rosenberg-Hasson, Y., Montoya, J. G.
2016; 90: 14-20

Abstract »

Majority of Toxoplasma gondii infections are benign and asymptomatic; however, some patients experience toxoplasmic lymphadenitis (TL). Factors associated as to whether infection will be symptomatic or not are unknown. Dye test titers of patients with acute toxoplasmosis (pregnant and not pregnant) with TL (TL+) were compared with those in patients with asymptomatic acute infection (TL-). Additionally, mean levels of 62 serum cytokines were compared between TL+ and TL- pregnant women and between TL+ pregnant and non-pregnant women. During acute infection, mean dye test titer was higher in TL+ than in TL- patients (p=0.021). In addition, out of 62 cytokines, CXCL9andCXCL10 levels were higher (p<0.05) and resistin mean levels were lower (p<0.05) in pregnant women with TL+ compared to TL-. Among patients with TL+, levels of VCAM1andCCL2 were lower (p<0.05) in pregnant women than in non-pregnant women. Here we report differences in dye test titers in patients with acute infection. Cytokine responses vary according to the presence of TL+ and to the pregnancy status. Factors underlying these differences are presently unknown and require further studies to define individual and combined roles of cytokines in TL+.

Laboratory Diagnosis of Congenital Toxoplasmosis. 
Journal of clinical microbiology
Pomares, C., Montoya, J. G.
2016; 54 (10): 2448-2454

Abstract »

Recent studies have demonstrated that screening and treatment for toxoplasmosis during gestation result in a decrease of vertical transmission and clinical sequelae. Early treatment was associated with improved outcomes. Thus, laboratory methods should aim for early identification of infants with congenital toxoplasmosis (CT). Diagnostic approaches should include, at least, detection of Toxoplasma IgG, IgM, and IgA and a comprehensive review of maternal history, including the gestational age at which the mother was infected and treatment. Here, we review laboratory methods for the diagnosis of CT, with emphasis on serological tools. A diagnostic algorithm that takes into account maternal history is presented.

Multiplexed Anti-Toxoplasma IgG, IgM, and IgA Assay on Plasmonic Gold Chips: towards Making Mass Screening Possible with Dye Test Precision
Li, X., Pomares, C., Gonfrier, G., Koh, B., Zhu, S., Gong, M., Montoya, J. G., Dai, H.
2016; 54 (7): 1726-1733

Abstract »

Toxoplasmosis is an infection caused by the protozoan parasite Toxoplasma gondii that can lead to severe sequelae in the fetus during pregnancy. Definitive serologic diagnosis of the infection during gestation is made mostly by detecting T. gondii-specific antibodies, including IgG and IgM, individually in a single serum sample by using commercially available kits. The IgA test is used by some laboratories as an additional marker of acute infection. Most of the commercial tests have failed to reach 100% correlation with the reference method, the Sabin-Feldman dye test for the detection of Toxoplasma IgG antibodies. For Toxoplasma IgM and IgA antibodies, there is no reference method and their evaluation is done by comparing the results of one assay to those of another. There is a need for multiplexed assay platforms, as the serological diagnosis of T. gondii infection does not rely on the detection of a single Ig subtype. Here we describe the development of a plasmonic gold chip with vast fluorescence enhancement in the near-infrared region for simultaneous detection of IgG, IgM, and IgA antibodies against T. gondii in an ∼1-μl serum or whole-blood sample. When 168 samples were tested on this platform, IgG antibody detection sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were all 100%. IgM antibody detection achieved 97.6% sensitivity and 96.9% specificity with a 90.9% PPV and a 99.2% NPV. Thus, the nanoscience-based plasmonic gold platform enables a high-performance, low-cost, multiplexed assay requiring ultra small blood volumes, paving the way for the implementation of universal screening for toxoplasmosis infection during gestation.

Failure of primary atovaquone prophylaxis for prevention of toxoplasmosis in hematopoietic cell transplant recipients 
Gajurel, K., Gomez, C. A., Dhakal, R., Vogel, H., Montoya, J. G.
2016; 18 (3): 446-452

Significance of a Positive Toxoplasma Immunoglobulin M Test Result in the United States
Dhakal, R., Gajurel, K., Pomares, C., Talucod, J., Press, C. J., Montoya, J. G.
2015; 53 (11): 3601-3605

Abstract »

A positive Toxoplasma immunoglobulin M (IgM) result is often interpreted as a marker of an acute infection. However, IgM can persist for several years, and Toxoplasma commercial IgM diagnostic test kits can yield a number of false-positive results. For these reasons, a chronic Toxoplasma infection can be erroneously classified as an acute infection, resulting in serious adverse consequences, especially in pregnant women, leading to emotional distress and unnecessary interventions, including termination of pregnancy. Interpretation of Toxoplasma serology at a reference laboratory can help differentiate a recently acquired infection from a chronic infection. Serological test results for 451 patients with positive Toxoplasma IgM and IgG test results obtained at nonreference laboratories (NRLs) that were referred to Palo Alto Medical Foundation Toxoplasma Serology Laboratory (PAMF-TSL) to determine whether the patient was acutely or chronically infected were retrospectively reviewed. PAMF-TSL results established that of the 451 patients, 335 (74%) had a chronic infection, 100 (22%) had an acute infection, and 7 (2%) were not infected, and for 9 (2%), results were indeterminate. Positive Toxoplasma IgM and IgG test results obtained at NRLs cannot accurately distinguish between acute and chronic infections. To do so, testing at reference laboratories is required, as mandated in 1997 in a letter from the Food and Drug Administration (FDA) to clinicians and laboratories in the United States.

Toxoplasma prophylaxis in haematopoietic cell transplant recipients: a review of the literature and recommendations 
Gajurel, K., Dhakal, R., Montoya, J. G.
2015; 28 (4): 283-292

Abstract »

Toxoplasmosis in haematopoietic cell transplant (HCT) recipients is associated with high morbidity and mortality rates. Prophylaxis following HCT is recommended for high-risk pre-HCT toxoplasma-seropositive (pre-HCTSP) recipients. However, there is no agreement or consistency among programmes on whether to adopt prophylaxis or not, or if used, on the chosen antitoxoplasma prophylactic regimen. This review discusses the role of prophylaxis, and preemptive treatment, for toxoplasmosis in the setting of HCT.Approximately two-thirds of toxoplasmosis cases following HCT are reported in allogeneic pre-HCTSP (allo pre-HCTSP) patients. This finding confirms a major role of reactivation of latent infection in the pathogenesis of toxoplasmosis in this patient population. Toxoplasma disease-related mortality in allo pre-HCTSP patients was reported at 62%, but it can be significantly decreased with early detection and treatment of toxoplasma infection. There are no randomized trials comparing the efficacy of different prophylactic agents to prevent toxoplasmosis after HCT. Several observational studies have demonstrated the efficacy of trimethoprim-sulfamethoxazole (TMP/SMX) in decreasing the incidence of toxoplasmosis following HCT. There is limited information regarding efficacy of other prophylactic agents. Preemptive treatment using routine blood PCR monitoring seems to be beneficial in detecting infection early and preventing disease in several observational studies and has been adopted for allo pre-HCTSP HCT patients when universal prophylaxis is not possible.Universal prophylaxis with TMP/SMX in allo pre-HCTSP patients should be implemented by all transplant programmes. Preemptive treatment with routine blood PCR monitoring is an option if prophylaxis cannot be used.

Distinct plasma immune signatures in ME/CFS are present early in the course of illness. 
Science advances
Hornig, M., Montoya, J. G., Klimas, N. G., Levine, S., Felsenstein, D., Bateman, L., Peterson, D. L., Gottschalk, C. G., Schultz, A. F., Che, X., Eddy, M. L., Komaroff, A. L., Lipkin, W. I.
2015; 1 (1)

Abstract »

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is an unexplained incapacitating illness that may affect up to 4 million people in the United States alone. There are no validated laboratory tests for diagnosis or management despite global efforts to find biomarkers of disease. We considered the possibility that inability to identify such biomarkers reflected variations in diagnostic criteria and laboratory methods as well as the timing of sample collection during the course of the illness. Accordingly, we leveraged two large, multicenter cohort studies of ME/CFS to assess the relationship of immune signatures with diagnosis, illness duration, and other clinical variables. Controls were frequency-matched on key variables known to affect immune status, including season of sampling and geographic site, in addition to age and sex. We report here distinct alterations in plasma immune signatures early in the course of ME/CFS (n = 52) relative to healthy controls (n = 348) that are not present in subjects with longer duration of illness (n = 246). Analyses based on disease duration revealed that early ME/CFS cases had a prominent activation of both pro- and anti-inflammatory cytokines as well as dissociation of intercytokine regulatory networks. We found a stronger correlation of cytokine alterations with illness duration than with measures of illness severity, suggesting that the immunopathology of ME/CFS is not static. These findings have critical implications for discovery of interventional strategies and early diagnosis of ME/CFS.

Right arcuate fasciculus abnormality in chronic fatigue syndrome. 
Zeineh, M. M., Kang, J., Atlas, S. W., Raman, M. M., Reiss, A. L., Norris, J. L., Valencia, I., Montoya, J. G.
2015; 274 (2): 517-526

Abstract »

Purpose To identify whether patients with chronic fatigue syndrome ( CFS chronic fatigue syndrome ) have differences in gross brain structure, microscopic structure, or brain perfusion that may explain their symptoms. Materials and Methods Fifteen patients with CFS chronic fatigue syndrome were identified by means of retrospective review with an institutional review board-approved waiver of consent and waiver of authorization. Fourteen age- and sex-matched control subjects provided informed consent in accordance with the institutional review board and HIPAA. All subjects underwent 3.0-T volumetric T1-weighted magnetic resonance (MR) imaging, with two diffusion-tensor imaging ( DTI diffusion-tensor imaging ) acquisitions and arterial spin labeling ( ASL arterial spin labeling ). Open source software was used to segment supratentorial gray and white matter and cerebrospinal fluid to compare gray and white matter volumes and cortical thickness. DTI diffusion-tensor imaging data were processed with automated fiber quantification, which was used to compare piecewise fractional anisotropy ( FA fractional anisotropy ) along 20 tracks. For the volumetric analysis, a regression was performed to account for differences in age, handedness, and total intracranial volume, and for the DTI diffusion-tensor imaging , FA fractional anisotropy was compared piecewise along tracks by using an unpaired t test. The open source software segmentation was used to compare cerebral blood flow as measured with ASL arterial spin labeling. Results In the CFS chronic fatigue syndrome population, FA fractional anisotropy was increased in the right arcuate fasciculus (P = .0015), and in right-handers, FA fractional anisotropy was also increased in the right inferior longitudinal fasciculus ( ILF inferior longitudinal fasciculus ) (P = .0008). In patients with CFS chronic fatigue syndrome , right anterior arcuate FA fractional anisotropy increased with disease severity (r = 0.649, P = .026). Bilateral white matter volumes were reduced in CFS chronic fatigue syndrome (mean ± standard deviation, 467 581 mm(3) ± 47 610 for patients vs 504 864 mm(3) ± 68 126 for control subjects, P = .0026), and cortical thickness increased in both right arcuate end points, the middle temporal (T = 4.25) and precentral (T = 6.47) gyri, and one right ILF inferior longitudinal fasciculus end point, the occipital lobe (T = 5.36). ASL arterial spin labeling showed no significant differences. Conclusion Bilateral white matter atrophy is present in CFS chronic fatigue syndrome . No differences in perfusion were noted. Right hemispheric increased FA fractional anisotropy may reflect degeneration of crossing fibers or strengthening of short-range fibers. Right anterior arcuate FA fractional anisotropy may serve as a biomarker for CFS chronic fatigue syndrome . © RSNA, 2014 Online supplemental material is available for this article.

Ocular toxoplasmosis in the United States: recent and remote infections. 
Clinical infectious diseases 
Jones, J. L., Bonetti, V., Holland, G. N., Press, C., Sanislo, S. R., Khurana, R. N., Montoya, J. G.
2015; 60 (2): 271-273

Abstract »

We tested all samples from patients with ocular toxoplasmosis sent to the Palo Alto Medical Foundation Toxoplasma Reference Laboratory from June 2004 through August 2010 for serologic evidence of recent Toxoplasma gondii infection. Of 205 patients aged 10-96 years, 11.7% had recent infection. Many people develop ocular disease soon after T. gondii infection.

Immune Profiling of Pregnant Toxoplasma-Infected US and Colombia Patients Reveals Surprising Impacts of Infection on Peripheral Blood Cytokines. 
Journal of Infectious Diseases
Pernas, L., Ramirez, R., Holmes, T. H., Montoya, J. G., Boothroyd, J. C.
2014; 210 (6): 923-931

Abstract »

In North America (NA) and Europe, the majority of toxoplasmosis cases are benign and generally asymptomatic, while in South America (SA) toxoplasmosis is associated with much more severe symptoms in adults and congenitally infected children. The reasons for these differences remain unknown and, currently, there is little information from patients in either region on how the immune system responds to infection with Toxoplasma gondii. Here, we report the relative abundance of 51 serum cytokines from acute and chronic toxoplasmosis cohorts of pregnant women from the United States (US), where approximately one-half of clinical isolates are Type II, and Colombia, where clinical isolates are generally "atypical" or Type I-like strains. Surprisingly, the results showed notably lower levels of 23 cytokines in acutely infected patients from the US, relative to uninfected US controls. In acutely infected Colombian patients, however, only 8 cytokine levels differed detectably with four being lower and four higher relative to uninfected controls. Strikingly, there were also differences in the cytokine profiles of the chronically infected patients relative to uninfected controls in the US cohort. Hence, Toxoplasma appears to specifically impact levels of circulating cytokines and our results may partly explain region-specific differences in the clinical spectrum of toxoplasmosis.

Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections: 2014 Update by the Infectious Diseases Society of America 
Stevens, D. L., Bisno, A. L., Chambers, H. F., Dellinger, E. P., Goldstein, E. J., Gorbach, S. L., Hirschmann, J. V., Kaplan, S. L., Montoya, J. G., Wade, J. C.
2014; 59 (2): E10-E52

Abstract »

A panel of national experts was convened by the Infectious Diseases Society of America (IDSA) to update the 2005 guidelines for the treatment of skin and soft tissue infections (SSTIs). The panel's recommendations were developed to be concordant with the recently published IDSA guidelines for the treatment of methicillin-resistant Staphylococcus aureus infections. The focus of this guideline is the diagnosis and appropriate treatment of diverse SSTIs ranging from minor superficial infections to life-threatening infections such as necrotizing fasciitis. In addition, because of an increasing number of immunocompromised hosts worldwide, the guideline addresses the wide array of SSTIs that occur in this population. These guidelines emphasize the importance of clinical skills in promptly diagnosing SSTIs, identifying the pathogen, and administering effective treatments in a timely fashion.

Antifungal prophylaxis following heart transplantation: systematic review 
Uribe, L. G., Cortes, J. A., Granados, C. E., Montoya, J. G.
2014; 57 (7): 429-436

Abstract »

Patients with heart transplantation have a high incidence of infectious complications, especially fungal infections. The aim of the systematic review was to determine the best pharmacological strategy to prevent fungal infections among patients with heart transplant. We searched the PubMed and Embase databases for studies reporting the effectivenesss of pharmacologic strategies to prevent fungal infections in adult patient with a heart transplant. Our search yielded five studies (1176 patients), four of them with historical controls. Two studies used inhaled amphotericin B deoxycholate, three used itraconazole and one used targeted echinocandin. All studies showed significant reduction in the prophylaxis arm. Different products, doses and outcomes were noted. There is a highly probable benefit of prophylaxis use, however, better studies with standardised doses and comparators should be performed.

Polymerase chain reaction in cerebrospinal fluid for the diagnosis of congenital toxoplasmosis.
Pediatric infectious disease journal
Olariu, T. R., Remington, J. S., Montoya, J. G.
2014; 33 (6): 566-570

Abstract »

Congenital toxoplasmosis (CT) can result in visual impairment, hearing loss, serious neurologic sequelae and death in the infant. We studied the potential of the polymerase chain reaction (PCR) in cerebrospinal fluid (CSF) for diagnosis of congenital toxoplasmosis.For this purpose we studied both congenitally infected (diagnosed clinically and serologically) and non-infected infants born to untreated mothers.The infants ranged in age from 0 to 180 days. CSF PCR was positive in 27 of the 58 (46.5%) congenitally infected infants and was negative in each of the 103 infants without CT. The frequency of positive CSF PCR varied according to whether infants had major clinical signs of the disease; PCR was positive in 70.9%, 53.3% and 50.9% of those with hydrocephalus, cerebral calcifications and/or eye disease, respectively. Three of six infants who were negative for both IgM and IgA antibodies had a positive PCR in their CSF as the confirmatory test for diagnosis of congenital toxoplasmosis. IgM and IgA antibodies and CSF PCR, when combined, yielded a higher sensitivity for diagnosis of congenital toxoplasmosis when compared with the performance of each test alone.Our findings reveal that in infants with clinical and serologic findings suggestive of congenital toxoplasmosis and born to untreated mothers, CSF PCR has the potential to increase the frequency of cases in which the diagnosis is confirmed.

Acute Toxoplasma gondii Infection among Family Members in the United States 
Contopoulos-Ioannidis, D. G., Maldonado, Y., Montoya, J. G.
2013; 19 (12): 1981-1984

Abstract »

We investigated 32 families of persons with acute toxoplasmosis in which > or = 1 other family member was tested for Toxoplasma gondii infection; 18 (56%) families had > or = 1 additional family member with acute infection. Family members of persons with acute toxoplasmosis should be screened for

Randomized Clinical Trial to Evaluate the Efficacy and Safety of Valganciclovir in a Subset of Patients With Chronic Fatigue Syndrome 
Montoya, J. G., Kogelnik, A. M., Bhangoo, M., Lunn, M. R., Flamand, L., Merrihew, L. E., Watt, T., Kubo, J. T., Paik, J., Desai, M.
2013; 85 (12): 2101-2109

Abstract »

There is no known treatment for chronic fatigue syndrome (CFS). Little is known about its pathogenesis. Human herpesvirus 6 (HHV-6) and Epstein-Barr virus (EBV) have been proposed as infectious triggers. Thirty CFS patients with elevated IgG antibody titers against HHV-6 and EBV were randomized 2:1 to receive valganciclovir (VGCV) or placebo for 6 months in a double-blind, placebo-controlled trial. Clinical endpoints aimed at measuring physical and mental fatigue included the Multidimensional Fatigue Inventory (MFI-20) and Fatigue Severity Scale (FSS) scores, self-reported cognitive function, and physician-determined responder status. Biological endpoints included monocyte and neutrophil counts and cytokine levels. VGCV patients experienced a greater improvement by MFI-20 at 9 months from baseline compared to placebo patients but this difference was not statistically significant. However, statistically significant differences in trajectories between groups were observed in MFI-20 mental fatigue subscore (P = 0.039), FSS score (P = 0.006), and cognitive function (P = 0.025). VGCV patients experienced these improvements within the first 3 months and maintained that benefit over the remaining 9 months. Patients in the VGCV arm were 7.4 times more likely to be classified as responders (P = 0.029). In the VGCV arm, monocyte counts decreased (P < 0.001), neutrophil counts increased (P = 0.037) and cytokines were more likely to evolve towards a Th1-profile (P < 0.001). Viral IgG antibody titers did not differ between arms. VGCV may have clinical benefit in a subset of CFS patients independent of placebo effect, possibly mediated by immunomodulation and/or antiviral effect. Further investigation with longer treatment duration and a larger sample size is warranted.

Utility of DNA Sequencing for Direct Identification of Invasive Fungi From Fresh and Formalin-Fixed Specimens 
Moncada, P. A., Budvytiene, I., Ho, D. Y., Deresinski, S. C., Montoya, J. G., Banaei, N.
2013; 140 (2): 203-208

Abstract »

Objectives: To describe and discuss the utility and potential pitfalls of ribosomal RNA locus sequencing for direct identification of invasive fungi from fresh and formalin-fixed, paraffin-embedded specimens. Methods: DNA was extracted from fresh and formalin-fixed, paraffin-embedded tissue and subjected to real-time polymerase chain reaction (PCR) targeting ITS2 and D2 regions of fungal ribosomal RNA locus. Cycle sequencing was performed on PCR products, and the identity of sequences was determined using a public database. Results: Four clinical cases of invasive fungal infection are presented to illustrate the utility of DNA sequencing for determining etiology when microbiological culture is negative, for shortening the time to identification of slow-growing fungi, for guiding antifungal therapy, and for shedding light on the pathogenesis of disseminated fungal infection. Conclusions: Fungal ribosomal RNA locus sequencing from fresh or formalin-fixed, paraffin-embedded specimens is a powerful tool for rapid and accurate diagnosis of patients with culture-negative or uncultured invasive mycosis.

Risk factors and outcomes in lung transplant recipients with nodular invasive pulmonary aspergillosis 
Singh, N., Suarez, J. F., Avery, R., Lass-Floerl, C., Geltner, C., Pasqualotto, A. C., Lyon, G. M., Barron, M., Husain, S., Wagener, M. M., Montoya, J. G.
2013; 67 (1): 72-78

Abstract »

Whether nodular lesions have specific risk-factors or influence outcomes in lung transplant recipients with invasive aspergillosis, is not fully known. The study population consisted of 64 consecutive lung transplant recipients with proven or probable invasive aspergillosis. Nodules, with or without halo/air crescent-sign were considered nodular presentations. Outcomes assessed were response rate (successful versus unsuccessful outcome) and all-cause mortality at 12 weeks.Overall, 34 patients had nodular and 30 had non-nodular lesions. Presence of nodular lesions was less likely to be associated with renal failure at baseline (adjusted OR 0.21, 95% CI, 0.04-0.97, p = 0.047), CMV infection (adjusted OR 0.18, 95% CI 0.04-0.75, p = 0.019) and receipt of antifungal prophylaxis (adjusted OR 0.22, 95% CI, 0.06-0.88, p = 0.032). Successful outcome and mortality rates in the study patients were 64.0% (41/64) and 25.0% (16/64), respectively. Nodular aspergillosis was associated with significantly higher successful outcome (adjusted OR 3.35, 95% CI, 1.06-10.54, p = 0.039) and lower mortality at 12 weeks (adjusted OR 0.20, 0.05-0.78, p = 0.021).Lung transplant recipients with nodular lesions due to invasive aspergillosis had better outcomes than those without such lesions.

Risk factors and outcomes in lung transplant recipients with nodular invasive pulmonary aspergillosis. 
Journal of Infection
Singh, N., Suarez, J. F., Avery, R., Lass-Flörl, C., Geltner, C., Pasqualotto, A. C., Marshall Lyon, G., Barron, M., Husain, S., Wagener, M. M., Montoya, J. G.
2013; 67 (1): 72-78

Abstract »

Whether nodular lesions have specific risk-factors or influence outcomes in lung transplant recipients with invasive aspergillosis, is not fully known.The study population consisted of 64 consecutive lung transplant recipients with proven or probable invasive aspergillosis. Nodules, with or without halo/air crescent-sign were considered nodular presentations. Outcomes assessed were response rate (successful versus unsuccessful outcome) and all-cause mortality at 12 weeks.Overall, 34 patients had nodular and 30 had non-nodular lesions. Presence of nodular lesions was less likely to be associated with renal failure at baseline (adjusted OR 0.21, 95% CI, 0.04-0.97, p = 0.047), CMV infection (adjusted OR 0.18, 95% CI 0.04-0.75, p = 0.019) and receipt of antifungal prophylaxis (adjusted OR 0.22, 95% CI, 0.06-0.88, p = 0.032). Successful outcome and mortality rates in the study patients were 64.0% (41/64) and 25.0% (16/64), respectively. Nodular aspergillosis was associated with significantly higher successful outcome (adjusted OR 3.35, 95% CI, 1.06-10.54, p = 0.039) and lower mortality at 12 weeks (adjusted OR 0.20, 0.05-0.78, p = 0.021).Lung transplant recipients with nodular lesions due to invasive aspergillosis had better outcomes than those without such lesions.

Daily cytokine fluctuations, driven by leptin, are associated with fatigue severity in chronic fatigue syndrome: evidence of inflammatory pathology. 
Journal of translational medicine
Stringer, E. A., Baker, K. S., Carroll, I. R., Montoya, J. G., Chu, L., Maecker, H. T., Younger, J. W.
2013; 11: 93-?

Abstract »

Chronic fatigue syndrome (CFS) is a debilitating disorder characterized by persistent fatigue that is not alleviated by rest. The lack of a clearly identified underlying mechanism has hindered the development of effective treatments. Studies have demonstrated elevated levels of inflammatory factors in patients with CFS, but findings are contradictory across studies and no biomarkers have been consistently supported. Single time-point approaches potentially overlook important features of CFS, such as fluctuations in fatigue severity. We have observed that individuals with CFS demonstrate significant day-to-day variability in their fatigue severity.Therefore, to complement previous studies, we implemented a novel longitudinal study design to investigate the role of cytokines in CFS pathophysiology. Ten women meeting the Fukuda diagnostic criteria for CFS and ten healthy age- and body mass index (BMI)-matched women underwent 25 consecutive days of blood draws and self-reporting of symptom severity. A 51-plex cytokine panel via Luminex was performed for each of the 500 serum samples collected. Our primary hypothesis was that daily fatigue severity would be significantly correlated with the inflammatory adipokine leptin, in the women with CFS and not in the healthy control women. As a post-hoc analysis, a machine learning algorithm using all 51 cytokines was implemented to determine whether immune factors could distinguish high from low fatigue days.Self-reported fatigue severity was significantly correlated with leptin levels in six of the participants with CFS and one healthy control, supporting our primary hypothesis. The machine learning algorithm distinguished high from low fatigue days in the CFS group with 78.3% accuracy.Our results support the role of cytokines in the pathophysiology of CFS.

Response to valganciclovir in chronic fatigue syndrome patients with human herpesvirus 6 and Epstein-Barr virus IgG antibody titers 
Watt, T., Oberfoell, S., Balise, R., Lunn, M. R., Kar, A. K., Merrihew, L., Bhangoo, M. S., Montoya, J. G.
2012; 84 (12): 1967-1974

Abstract »

Valganciclovir has been reported to improve physical and cognitive symptoms in patients with chronic fatigue syndrome (CFS) with elevated human herpesvirus 6 (HHV-6) and Epstein-Barr virus (EBV) IgG antibody titers. This study investigated whether antibody titers against HHV-6 and EBV were associated with clinical response to valganciclovir in a subset of CFS patients. An uncontrolled, unblinded retrospective chart review was performed on 61 CFS patients treated with 900 mg valganciclovir daily (55 of whom took an induction dose of 1,800 mg daily for the first 3 weeks). Antibody titers were considered high if HHV-6 IgG ≥ 1:320, EBV viral capsid antigen (VCA) IgG ≥ 1:640, and EBV early antigen (EA) IgG ≥ 1:160. Patients self-rated physical and cognitive functioning as a percentage of their functioning prior to illness. Patients were categorized as responders if they experienced at least 30% improvement in physical and/or cognitive functioning. Thirty-two patients (52%) were categorized as responders. Among these, 19 patients (59%) responded physically and 26 patients (81%) responded cognitively. Baseline antibody titers showed no significant association with response. After treatment, the average change in physical and cognitive functioning levels for all patients was +19% and +23%, respectively (P < 0.0001). Longer treatment was associated with improved response (P = 0.0002). No significant difference was found between responders and non-responders among other variables analyzed. Valganciclovir treatment, independent of the baseline antibody titers, was associated with self-rated improvement in physical and cognitive functioning for CFS patients who had positive HHV-6 and/or EBV serologies. Longer valganciclovir treatment correlated with an improved response.

Toxoplasmosis in the fetus and newborn: an update on prevalence, diagnosis and treatment 
Moncada, P. A., Montoya, J. G.
2012; 10 (7): 815-828

Abstract »

Toxoplasma gondii is an unicellular coccidian parasite with worldwide distribution. It is estimated that more than a third of the world's population has been infected with the parasite, but seroprevalence is unevenly distributed across countries and different socioeconomic strata. The majority of newborns with congenital toxoplasmosis do not have any clinical signs of the disease at birth; however, 30-70% of those with clinical abnormalities were not detected initially, and are found to have new retinal lesions consistent with toxoplasmicchorioretinitis later in life. Congenital toxoplasmosis can also cause fetal death, stillbirths or long-term disabling sequelae, particularly among untreated infants. The disease appears to be more frequent and severe at certain latitudes. Congenital toxoplasmosis can be prevented and treated during gestation. Less severe disease is commonly reported in countries where prenatal screening and treatment have been systematically implemented. By contrast, severe disease appears to be observed primarily in infants born to untreated mothers. For definition purposes, it is best to use the term toxoplasma or Toxoplasma gondii infection when referring to asymptomatic patients with primary or chronic infection, and toxoplasmosis when referring to patients with symptoms or signs.

Severe Congenital Toxoplasmosis in the United States Clinical and Serologic Findings in Untreated Infants 
Olariu, T. R., Remington, J. S., McLeod, R., Alam, A., Montoya, J. G.
2011; 30 (12): 1056-1061

Abstract »

Congenital toxoplasmosis can cause significant neurologic manifestations and other untoward sequelae.The Palo Alto Medical Foundation Toxoplasma Serology Laboratory database was searched for data on infants 0 to 180 days old, in whom congenital toxoplasmosis had been confirmed and who had been tested for Toxoplasma gondii-specific immunoglobulin G (IgG), IgM, and IgA antibodies, between 1991 and 2005. Their clinical findings were confirmed at the National Collaborative Chicago-based Congenital Toxoplasmosis Study center. We reviewed available clinical data and laboratory profiles of 164 infants with congenital toxoplasmosis whose mothers had not been treated for the parasite during gestation.One or more severe clinical manifestations of congenital toxoplasmosis were reported in 84% of the infants and included eye disease (92.2%), brain calcifications (79.6%), and hydrocephalus (67.7%). In 61.6% of the infants, eye disease, brain calcifications, and hydrocephalus were present concurrently. T. gondii-specific IgM, IgA, and IgE antibodies were demonstrable in 86.6%, 77.4%, and 40.2% of the infants, respectively. Testing for IgM and IgA antibodies increased the sensitivity of making the diagnosis of congenital toxoplasmosis to 93% compared with testing for IgM or IgA individually. IgM and IgA antibodies were still present in 43.9% of infants diagnosed between 1 and 6 months of life.Our study reveals that severe clinical signs of congenital toxoplasmosis including hydrocephalus, eye disease, or intracranial calcifications occurred in 85% infants whose sera were referred to our reference Toxoplasma Serology Laboratory during a period of 15 years. Laboratory tests, including serologic and polymerase chain reaction tests, were critical for diagnosis in the infants. Our results contrast remarkably with those of European investigators who rarely observe severe clinical signs in infants with congenital toxoplasmosis.

Diagnostic Approach to Ocular Toxoplasmosis 
Garweg, J. G., de Groot-Mijnes, J. D., Montoya, J. G.
2011; 19 (4): 255-261

Abstract »

Toxoplasmic retinochoroiditis is deemed a local event, which may fail to evoke a detectable systemic immune response. A correct diagnosis of the disease is a necessary basis for estimating its clinical burden. This is not so difficult in a typical clinical picture. In atypical cases, further diagnostic efforts are to be installed. Although the aqueous humor may be analyzed for specific antibodies or the presence of parasitic DNA, the DNA burden therein is low, and in rare instances a confirmation would necessitate vitreous sampling. A laboratory confirmation of the diagnosis is frustrated by individual differences in the time elapsing between clinical symptoms and activation of specific antibody production, which may result in false negatives. In congenital ocular toxoplasmosis, a delay in the onset of specific local antibody production could reflect immune tolerance. Herein, the authors attempt to provide a simple and practicable algorithm for a clinically tailored diagnostic approach in atypical instances.

Yield of diagnostic procedures for invasive fungal infections in neutropenic febrile patients with chest computed tomography abnormalities
Ho, D. Y., Lin, M., Schaenman, J., Rosso, F., Leung, A. N., Coutre, S. E., Sista, R. R., Montoya, J. G.
2011; 54 (1): 59-70

Abstract »

Haematological patients with neutropenic fever are frequently evaluated with chest computed tomography (CT) to rule out invasive fungal infections (IFI). We retrospectively analysed data from 100 consecutive patients with neutropenic fever and abnormal chest CT from 1998 to 2005 to evaluate their chest CT findings and the yield of diagnostic approaches employed. For their initial CTs, 79% had nodular opacities, with 24.1% associated with the halo sign. Other common CT abnormalities included pleural effusions (48%), ground glass opacities (37%) and consolidation (31%). The CT findings led to a change in antifungal therapy in 54% of the patients. Fifty-six patients received diagnostic procedures, including 46 bronchoscopies, 25 lung biopsies and seven sinus biopsies, with a diagnostic yield for IFI of 12.8%, 35.0% and 83.3%, respectively. In conclusion, chest CT plays an important role in the evaluation of haematological patients with febrile neutropenia and often leads to a change in antimicrobial therapy. Pulmonary nodules are the most common radiological abnormality. Sinus or lung biopsies have a high-diagnostic yield for IFI as compared to bronchoscopy. Patients with IFI may not have sinus/chest symptoms, and thus, clinicians should have a low threshold for performing sinus/chest imaging, and if indicated and safe, a biopsy of the abnormal areas.

Changing trends in infectious disease in heart transplantation 
Haddad, F., Deuse, T., Pham, M., Khazanie, P., Rosso, F., Luikart, H., Valantine, H., Leon, S., Vu, T. A., Hunt, S. A., Oyer, P., Montoya, J. G.
2010; 29 (3): 306-315

Abstract »

During the past 25 years, advances in immunosuppression and the use of selective anti-microbial prophylaxis have progressively reduced the risk of infection after heart transplantation. This study presents a historical perspective of the changing trends of infectious disease after heart transplantation.Infectious complications in 4 representative eras of immunosuppression and anti-microbial prophylaxis were analyzed: (1) 38 in the pre-cyclosporine era (1978-1980), (2) 72 in the early cyclosporine era (1982-1984), where maintenance immunosuppression included high-dose cyclosporine and corticosteroid therapy; (3) 395 in the cyclosporine era (1988-1997), where maintenance immunosuppression included cyclosporine, azathioprine, and lower corticosteroid doses; and (4) 167 in the more recent era (2002-2005), where maintenance immunosuppression included cyclosporine and mycophenolate mofetil.The overall incidence of infections decreased in the 4 cohorts from 3.35 episodes/patient to 2.03, 1.35, and 0.60 in the more recent cohorts (p < 0.001). Gram-positive bacteria are emerging as the predominant cause of bacterial infections (28.6%, 31.4%, 51.0%, 67.6%, p = 0.001). Cytomegalovirus infections have significantly decreased in incidence and occur later after transplantation (88 +/- 77 days, pre-cyclosporine era; 304 +/- 238 days, recent cohort; p < 0.001). Fungal infections also decreased, from an incidence of 0.29/patient in the pre-cyclosporine era to 0.08 in the most recent era. A major decrease in Pneumocystis jiroveci and Nocardia infections has also occurred. The overall incidence and mortality associated with infections continues to decrease in heart transplantation and coincides with advances in immunosuppression, the use of selective anti-microbial prophylaxis, and more effective treatment regimens.

Risk Factors for Toxoplasma gondii Infection in the United States 
Jones, J. L., Dargelas, V., Roberts, J., Press, C., Remington, J. S., Montoya, J. G.
2009; 49 (6): 878-884

Abstract »

Toxoplasmosis can cause severe ocular and neurological disease. We sought to determine risk factors for Toxoplasma gondii infection in the United States.We conducted a case-control study of adults recently infected with T. gondii. Case patients were selected from the Palo Alto Medical Foundation Toxoplasma Serology Laboratory from August 2002 through May 2007; control patients were randomly selected from among T. gondii-seronegative persons. Data were obtained from serological testing and patient questionnaires.We evaluated 148 case patients with recent T. gondii infection and 413 control patients. In multivariate analysis, an elevated risk of recent T. gondii infection was associated with the following factors: eating raw ground beef (adjusted odds ratio [aOR], 6.67; 95% confidence limits [CLs], 2.09, 21.24; attributable risk [AR], 7%); eating rare lamb (aOR, 8.39; 95% CLs, 3.68, 19.16; AR, 20%); eating locally produced cured, dried, or smoked meat (aOR, 1.97; 95% CLs, 1.18, 3.28; AR, 22%); working with meat (aOR, 3.15; 95% CLs, 1.09, 9.10; AR, 5%); drinking unpasteurized goat's milk (aOR, 5.09; 95% CLs, 1.45, 17.80; AR, 4%); and having 3 or more kittens (aOR, 27.89; 95% CLs, 5.72, 135.86; AR, 10%). Eating raw oysters, clams, or mussels (aOR, 2.22; 95% CLs, 1.07, 4.61; AR, 16%) was significant in a separate model among persons asked this question. Subgroup results are also provided for women and for pregnant women.In the United States, exposure to certain raw or undercooked foods and exposure to kittens are risk factors for T. gondii infection. Knowledge of these risk factors will help to target prevention efforts.

Changing Trends in Infectious Complications among Heart Transplant Recipients 
29th Annual Meeting and Scientific Session of the International-Society-for-Heart-and-Lung-Transplantation
Haddad, F., Deuse, T., Rosso, P., Pham, M., Khazanie, P., Luikart, H., Valantine, H. A., Hunt, S. A., Vu, T., Oyer, P. E., Robbins, R. C., Montoya, J. G.

57th Annual Meeting of the American-Society-of-Tropical-Medicine-and-Hygiene
Jones, J. L., Dargelas, V., Roberts, J., Press, C., Remington, J. S., Montoya, J. G.

Management of Toxoplasma gondii infection during pregnancy 
Montoya, J. G., Remington, J. S.
2008; 47 (4): 554-566

Abstract »

Acute infection with Toxoplasma gondii during pregnancy and its potentially tragic outcome for the fetus and newborn continue to occur in the United States, as well as worldwide, despite the fact that it can be prevented. The infection can be acquired through ingestion of infected, undercooked meat or contaminated food or water. Transmission to the fetus occurs almost solely in women who acquire their primary infection during gestation and can result in visual and hearing loss, mental and psychomotor retardation, seizures, hematological abnormalities, hepatosplenomegaly, or death. Systematic education and serological screening of pregnant women are the most reliable and currently available strategies for the prevention, diagnosis, and early treatment of the infection in the offspring; this is largely because toxoplasmosis in pregnant women most often goes unrecognized. Treatment of the infection in the fetus and infant during the first year of life has been demonstrated to significantly improve the clinical outcome.

Prevalence of infection with Toxoplasma gondii among pregnant women in Cali, Colombia, South America 
Rosso, F., Les, J. T., Agudelo, A., Villalobos, C., Chaves, J. A., Tunubala, G. A., Messa, A., Remington, J. S., Montoya, J. G.
2008; 78 (3): 504-508

Abstract »

The aim of this study was to determine the prevalence of toxoplasma antibodies among pregnant women in Cali, Colombia. In 2005, 955 pregnant women were tested for IgG and IgM antibodies and sociodemographic information was collected. Their average age was 25.1 years, overall IgG seroprevalence 45.8% (95% CI: 41.8%, 48.2%), IgM 2.8% (95% CI: 1.5%, 3.6%). Seroprevalence increased significantly with age, 39.0% in 14 to 19 years to 55.3% in 30 to 39 years (P = 0.001). There was a significant trend toward a higher seroprevalence in the lower socioeconomic strata (SES) (low: 49.0%, high: 29%, P = 0.004). The increase in seroprevalence by age was more significant in the lower socioeconomic strata (P = 0.002). Our results suggest a higher prevalence when compared with those of the national 1980 (33-37.6%) survey. In contrast to reports from other regions of the world, Cali has not seen a decrease in T. gondii seroprevalence over the past 25 years.

The differential agglutination test as a diagnostic aid in cases of toxoplasmic lymphadenitis 
Montoya, J. G., Berry, A., Rosso, F., Remington, J. S.
2007; 45 (5): 1463-1468

Abstract »

Lymphadenopathy (LN) is the most common clinical manifestation of acute acquired toxoplasma infection in humans. The diagnosis of toxoplasmic lymphadenitis (TL) is established by serological methods and/or lymph node biopsy. In the United States, the differential agglutination (of acetone [AC]-fixed versus that of formalin [HS]-fixed tachyzoites) test (AC/HS test) has primarily been used in assessments of pregnant women as a component of the toxoplasma serological profile to distinguish between recently acquired infections and infections acquired in the distant past. We studied the AC/HS test in patients with TL to define its usefulness in diagnosing individuals presenting with LN and to determine its kinetics after the onset of LN. One hundred nine consecutive patients (158 serum samples) diagnosed serologically and by lymph node biopsy as having TL were studied. Specific patterns in the AC/HS test were noted to be dependent on the time from the clinical onset of LN (COLN). Acute AC/HS patterns were observed for more than 75% of patients who according to their histories had developed their TL within 6 months after COLN. Acute patterns were not observed beyond the 12th month except for a single patient for whom an acute pattern (400/800) persisted to the 13th month after COLN. Equivocal patterns were observed up to 36 months after COLN. Nonacute patterns were observed only for serum samples drawn at least 13 months after COLN. A nonacute pattern in an individual at less than 12 months after COLN should suggest an etiology other than TL. In such cases, investigation for alternative causes, including malignancy, should be instigated.

Diagnosis and management of toxoplasmosis 
Montoya, J. G., Rosso, F.
2005; 32 (3): 705

Abstract »

This article discusses the diagnosis and management of toxoplasmosis. Congenital toxoplasmosis continues to be a tragic outcome of a preventable and treatable infection. Education of patients, physicians and health policy makers on the primary and secondary preventive measures of the disease, and their execution, will undoubtedly result in lower incidence, morbidity, and mortality rates from congenital disease due to Toxoplasma gondii.

Scedosporium apiospermum soft tissue infection successfully treated with voriconazole: Potential pitfalls in the transition from intravenous to oral therapy 
Schaenman, J. M., DiGiulio, D. B., Mirels, L. F., McClenny, N. M., Berry, G. J., Fothergill, A. W., Rinaldi, M. G., Montoya, J. G.
2005; 43 (2): 973-977

Abstract »

An immunocompromised patient with an invasive soft tissue infection due to Scedosporium apiospermum was successfully treated with voriconazole and surgical debridement. After transition from intravenous to oral therapy, successive adjustments of the oral dose were required to achieve complete resolution. For soft tissue infections due to molds characterized by thin, septate hyphae branching at acute angles, voriconazole should be considered a first-line antifungal agent. The potential usefulness of plasma voriconazole levels for guiding optimal therapy should be investigated.

Evaluation of the immunoglobulin G avidity test for diagnosis of toxoplasmic lymphadenopathy 
Montoya, J. G., Huffman, H. B., Remington, J. S.
2004; 42 (10): 4627-4631

Abstract »

Toxoplasmic lymphadenopathy (TL) is the most common clinical manifestation of acute acquired toxoplasma infection in normal individuals. The diagnosis is established by serologic methods and lymph node biopsy. Recently, tests for avidity of toxoplasma immunoglobulin G (IgG) antibodies have been introduced to help discriminate between recently acquired and distant infection with the parasite. We studied an avidity test to define the usefulness of this method and to determine the evolution of the IgG avidity in TL. Seventy-three consecutive patients diagnosed as having TL were studied. IgG avidity test titers were noted to be time dependent from the clinical onset of lymphadenopathy. Low IgG avidity test results were observed in patients who had developed lymphadenopathy from <1 month to 17 months prior to the sampling of sera, emphasizing that low IgG avidity test results are not reliable for diagnosis of recently acquired infection. In contrast, high IgG avidity test results were observed only in patients who had developed lymphadenopathy at least 4 months earlier. Thus, a high IgG avidity test result in an individual who has recent onset of lymphadenopathy (e.g., within 2 to 3 months of sera sampling) suggests a cause other than toxoplasmosis. In such cases, further workup is warranted in order to determine the cause of the lymphadenopathy.

Successes and limitations of antimicrobial interventions in the setting of organ transplantation 
Montoya, J. G.
2004; 17 (4): 341-345

Montoya, J. G., Liesenfeld, O.
2004; 363 (9425): 1965-1976

Abstract »

Toxoplasma gondii is a protozoan parasite that infects up to a third of the world's population. Infection is mainly acquired by ingestion of food or water that is contaminated with oocysts shed by cats or by eating undercooked or raw meat containing tissue cysts. Primary infection is usually subclinical but in some patients cervical lymphadenopathy or ocular disease can be present. Infection acquired during pregnancy may cause severe damage to the fetus. In immunocompromised patients, reactivation of latent disease can cause life-threatening encephalitis. Diagnosis of toxoplasmosis can be established by direct detection of the parasite or by serological techniques. The most commonly used therapeutic regimen, and probably the most effective, is the combination of pyrimethamine with sulfadiazine and folinic acid. This Seminar provides an overview and update on management of patients with acute infection, pregnant women who acquire infection during gestation, fetuses or infants who are congenitally infected, those with ocular disease, and immunocompromised individuals. Controversy about the effectiveness of primary and secondary prevention in pregnant women is discussed. Important topics of current and future research are presented.

Recent developments for diagnosis of toxoplasmosis 
Remington, J. S., Thulliez, P., Montoya, J. G.
2004; 42 (3): 941-945

Invasive aspergillosis in the setting of cardiac transplantation 
37th Annual Meeting of the Infectious-Diseases-Society-of-America
Montoya, J. G., Chaparro, S. V., Celis, D., Cortes, J. A., Leung, A. N., Robbins, R. C., Stevens, D. A.

Abstract »

Among patients undergoing heart transplantation, Aspergillus is the opportunistic pathogen with the highest attributable mortality. The median time of onset from transplantation for invasive pulmonary aspergillosis (IPA) was 46 days, but the median time to first positive culture result was 104 days among patients with Aspergillus colonization but no invasive disease. Most patients with IPA presented with fever and cough within the first 90 days of transplantation and with single or multiple pulmonary nodules. None of the heart transplant recipients with either IPA or invasive extrapulmonary aspergillosis (IEPA) had associated neutropenia. Human leukocyte antigen A1 locus was found significantly more frequently among patients colonized with Aspergillus than among patients with IPA (P<.006) or IEPA (P<.001). Even in the absence of neutropenia, IPA should be suspected for heart transplant recipients who have fever and respiratory symptoms within the first 3 months of transplantation, have a positive result of culture of respiratory secretions, and have abnormal radiological findings (particularly nodules).

VIDAS test for avidity of Toxoplasma-specific immunoglobulin G for confirmatory testing of pregnant women 
Montoya, J. G., Liesenfeld, O., Kinney, S., Press, C., Remington, J. S.
2002; 40 (7): 2504-2508

Abstract »

Because congenital toxoplasmosis is almost solely the result of maternal infection acquired during gestation, it is critical to determine whether infection during pregnancy has occurred. In the United States, definitive diagnosis of the acute infection and the time of its occurrence have been compromised by a lack of systematic screening and the fact that only a single serum sample is submitted for testing. In studies in Europe, and depending on the method used, the demonstration of high-avidity immunoglobulin G (IgG) toxoplasma antibodies has been shown to exclude infection having occurred in the first 3 to 5 months of pregnancy. We investigated the usefulness of determining the avidity of IgG toxoplasma antibodies with a VIDAS kit (herein referred to as the VIDAS Toxo-IgG avidity kit, the VIDAS kit essentially rules out acute infection having occurred within the 4 prior months) in the setting of a reference serology laboratory in the United States. Sera (132 samples) from 132 women in the first 16 weeks of pregnancy were chosen because at least one test in the toxoplasma serological profile (TSP) suggested or was equivocal for a recently acquired infection. High-avidity antibodies were demonstrated in 75% of 99 sera positive with the IgM enzyme-linked immunosorbent assay (ELISA) and 31.3% of 16 sera with acute TSP results. A significant percentage of sera with equivocal results wtih the IgM ELISA or TSP also had high-avidity test results. Of 39 women for whom treatment with spiramycin had been suggested to attempt to prevent congenital transmission, 19 (48.7%) had high-avidity antibodies. These findings highlight the value of the VIDAS IgG avidity kit when used in combination with the TSP to exclude recent infection, especially when only a single serum sample is available.

Laboratory diagnosis of Toxoplasma gondii infection and toxoplasmosis 
Symposium on Insights on Infection and Immunity
Montoya, J. G.

Abstract »

 For the past 40 years, the Toxoplasma Serology Laboratory at the Palo Alto Medical Foundation Research Institute (TSL-PAMFRI) has been dedicated to the laboratory diagnosis of Toxoplasma gondii infection and toxoplasmosis. TSL-PAMFRI is the "brain child" of Jack S. Remington. Jack's ceaseless devotion to objectivity and uncompromising excellence has made TSL-PAMFRI the Toxoplasma reference laboratory for the Centers for Disease Control and Prevention, the US Food and Drug Administration, and health care providers and clinical laboratories in the United States and other countries. Jack's leadership and vision created, defined, and significantly contributed to the development of laboratory methods for the diagnosis of the infection and diseases caused by T. gondii. A summary of the laboratory tests currently available at TSL-PAMFRI for the diagnosis of infection and disease caused by the parasite is presented here.

Infectious complications among 620 consecutive heart transplant patients at Stanford University Medical Center 
10th International Symposium on Infections in the Immunocompromised
Montoya, J. G., Giraldo, L. F., Efron, B., Stinson, E. B., Gamberg, P., Hung, S., Giannetti, N., Miller, J., Remington, J. S.

Abstract »

A total of 1073 infectious episodes (IEs) that occurred in 620 consecutive heart transplantation patients at Stanford Medical Center between 16 December 1980 and 30 June 1996 were reviewed. Infectious complications were a major cause of morbidity and mortality, second only to rejection as the cause of early deaths and the most common cause of late deaths. Of the IEs, 468 (43.6%) were caused by bacteria, 447 (41.7%) by viruses, 109 (10.2%) by fungi, 43 (4.0%) by Pneumocystis carinii, and 6 (0.6%) by protozoa. The largest number of IEs occurred in the lungs (301 [28.1%]). A significant reduction in the incidence of IEs and a delay in presentation after transplantation were observed; these were most likely related to the introduction of new chemoprophylactic regimens during the study period and prevention of significant disease caused by cytomegalovirus.

Confirmatory serologic testing for acute toxoplasmosis and rate of induced abortions among women reported to have positive Toxoplasma immunoglobulin M antibody titers 
35th Annual Meeting of the Infectious-Diseases-Society-of-America
Liesenfeld, O., Montoya, J. G., Tathineni, N. J., Davis, M., Brown, B. W., Cobb, K. L., Parsonnet, J., Remington, J. S.
MOSBY-ELSEVIER. 2001: 140–45

Abstract »

Results obtained with commercial testing kits for immunoglobulin M Toxoplasma antibodies may be inaccurate or may be inaccurately interpreted, which may influence whether a woman decides to terminate the pregnancy. This study was undertaken to determine whether confirmatory testing at a reference laboratory and communication of the results and an expert interpretation to the patient's physician would affect the rate of induced abortions among pregnant women with positive results of testing for immunoglobulin M Toxoplasma antibodies in outside laboratories.This was a retrospective cohort study of 811 consecutive pregnant women for whom the toxoplasma serologic profile was performed at a reference laboratory. Almost all the patients had been informed by their physicians that a result of a test for immunoglobulin M Toxoplasma antibodies performed in an outside laboratory was positive. Women were separated into those with a toxoplasma serologic profile result suggestive of a recently acquired infection (group 1) and those with a result suggestive of an infection acquired in the more distant past (group 2). Physician reports of induced abortions were used to determine rates of induced abortion in groups 1 and 2.Of the 811 women 321 (39.6%) were considered likely to have a recent infection (group 1) and 490 (60.4%) were considered likely to have a past infection (group 2). Physicians reported pregnancy outcomes for 433 (53.4%) of 811 women (65.1% and 45.7% in groups 1 and 2, respectively). Whereas 36 of 209 women in group 1 (17.2%) terminated the pregnancy, only 1 of 224 women in group 2 (0.4%) chose abortion (P <.001).Confirmatory serologic testing in a reference laboratory and communication of the results and their correct interpretation by an expert to the patient's physician decreased the rate of unnecessary abortions by approximately 50% among women for whom positive immunoglobulin M Toxoplasma test results had been reported by outside laboratories.

Use of the polymerase chain reaction for diagnosis of ocular toxoplasmosis 
35th Annual Meeting of the Infectious-Diseases-Society-of-America
Montoya, J. G., Parmley, S., Liesenfeld, O., JAFFE, G. J., Remington, J. S.
ELSEVIER SCIENCE INC. 1999: 1554–63More

Abstract »

To report a cohort of patients in whom polymerase chain reaction (PCR) was performed on vitreous samples and to place in perspective the current role of PCR in the diagnosis of ocular toxoplasmosis.Noncomparative case series.Fifteen patients in whom toxoplasmic retinochoroiditis was considered in the differential diagnosis and in whom the clinical presentation was not diagnostic and/or response to treatment was inadequate.Examination of vitreous fluid by PCR and of serum for the presence of Toxoplasma-specific antibodies.Presence of Toxoplasma gondii DNA, serologic test results, clinical findings, treatment, and outcome.In 7 of 15 patients, vitreous fluid examination results by PCR were positive for the presence of T. gondii DNA. Five of these seven patients had serologic test results consistent with Toxoplasma infection acquired in the distant past; the other two patients had serologic test results consistent with retinochoroiditis in the setting of acute toxoplasmosis. The PCR results influenced the management of these patients in six of the seven positive cases. In the eight patients in whom vitreous examination results were negative by PCR, either Toxoplasma serology was negative (6), the retinal lesions were caused by cytomegalovirus (1), or, on further consideration, the eye signs were not consistent with those of toxoplasmic retinochoroiditis (1).In patients in whom toxoplasmosis is considered in the differential diagnosis but in whom the presentation is atypical, PCR was frequently a useful diagnostic aid.

Toxoplasmic myocarditis and polymyositis in patients with acute acquired toxoplasmosis diagnosed during life 
Montoya, J. G., Jordan, R., Lingamneni, S., Berry, G. J., Remington, J. S.
1997; 24 (4): 676-683

Abstract »

The presence of both toxoplasmic myocarditis and myositis in the same individual has been reported only at autopsy. We report the first case of biopsy-proven toxoplasmic myocarditis and polymyositis simultaneously occurring in the same individual that was diagnosed during life. Results of her toxoplasmic serology were consistent with acute toxoplasmosis. She subsequently developed visual symptoms consistent with toxoplasmic chorioretinitis. She had a positive clinical response to therapeutic agents specific against Toxoplasma gondii. Her toxoplasmic serological profile established the diagnosis of acute toxoplasmosis. A toxoplasmic serological profile should be obtained for patients with myocarditis and/or polymyositis of unclear etiology. Endomyocardial or skeletal muscle tissue biopsies may establish the definitive diagnosis of toxoplasmic myocarditis or polymyositis, respectively. Examination of blood by polymerase chain reaction analysis before antitoxoplasmic treatment and early in the course of primary infection with T. gondii may prove useful.

Toxoplasmic chorioretinitis in the setting of acute acquired toxoplasmosis 
Montoya, J. G., Remington, J. S.
1996; 23 (2): 277-282

Abstract »

Ocular toxoplasmosis is considered to be the most commonly recognized cause of chorioretinitis in the United States. It is commonly believed that the majority of cases of acute toxoplasmic chorioretinitis involving adults in the United States are late sequelae of congenital infection and that the condition is rarely associated with acute postnatally acquired infection. We report here the clinical and serological test findings for 22 adults with acute toxoplasmic chorioretinitis that occurred in the setting of acute postnatally acquired toxoplasmosis. The initial serum specimen from each adult yielded an acute toxoplasmic serological profile, on the basis of the following positive results: 95.5%, Sabin-Feldman dye test [titer of > or = 1:1,024]; 95.5%, IgM ELISA; 90.9%, IgA ELISA; 77.3%, IgE ELISA; 95.5%, IgE immunosorbent agglutination assay; and 86.4%, differential agglutination (AC/HS) test (acute pattern). Detection of IgA or IgE antibodies or an acute pattern in the AC/HS test was particularly helpful in diagnosis for those patients whose ELISA IgM titers at presentation were negative or lowly positive. Thus, acute toxoplasmic chorioretinitis occurring with a recently acquired Toxoplasma gondii infection would appear to be more common in the United States than previously recognized, and a toxoplasmic serological profile is useful in diagnosing this entity.

Human CD4(+) and CD8(+) T lymphocytes are both cytotoxic to Toxoplasma gondii-infected cells 
Montoya, J. G., Lowe, K. E., CLAYBERGER, C., Moody, D., Do, D., Remington, J. S., Talib, S., Subauste, C. S.
1996; 64 (1): 176-181

Abstract »

Studies to determine if Toxoplasma gondii-specific human T cells lyse parasite-infected cells have yielded conflicting results. Furthermore, attempts to obtain human cytotoxic CD8+ T lymphocytes have been difficult because of the lack of a reproducible system for their generation. By using paraformaldehyde-fixed, T. gondii-infected peripheral blood mononuclear cells as antigen-presenting cells, we developed a method whereby T. gondii-specific T-cell lines can be reproducibly generated. Six T. gondii-specific T-cell lines were generated from an individual chronically infected with T. gondii. Cytofluorometric analysis of these lines revealed > 99% CD3+, 85 to 95% CD3+ alpha beta T-cell-receptor-positive (TCR+), 5 to 9% CD3+ gamma delta TCR+, 50 to 70% CD4+, and 20 to 40% CD8+ cells when cells were examined during the first 3 weeks of stimulation and >99% CD3+, >99% CD3+ alpha beta TCR+, < 1% CD3+ gamma delta TCR+, 20 to 40% CD4+, and 60 to 80% CD8+ cells when cells were examined between 5 and 11 weeks. Both CD4+ and CD8+ T cells had remarkable cytotoxic activity against T. gondii-infected target cells (30 to 50% specific Cr release at an effector-to-target ratio of 30:1) but not against uninfected target cells ( < 10% at an effector-to-target ratio of 30:1). Cytotoxic activity by the whole T-cell lines was not T. gondii strain specific. Whole T-cell lines were cytotoxic for target cells infected with the C56 and ME49 strains and the RH strain (which was used to infect peripheral blood mononuclear cells). T. gondii-specific T-cell lines displayed the predominant expression of V beta 7 TCR. The CDR3 regions of the V beta 7 TCRs of these T-cell lines showed a striking degree of sequence identity (oligoclonality). T-cell lines obtained by the method reporter here can be used to characterize functional activity of T-lymphocyte subsets in humans infected with T. gondii.