Guidelines for the management of Toxoplasma gondii infection and disease in patients with haematological malignancies and after haematopoietic stem-cell transplantation: guidelines from the 9th European Conference on Infections in Leukaemia, 2022

Patients with haematological malignancies might develop life-threatening toxoplasmosis, especially after allogeneic haematopoietic stem-cell transplantation (HSCT). Reactivation of latent cysts is the primary mechanism of toxoplasmosis following HSCT; hence, patients at high risk are those who were seropositive before transplantation. The lack of trimethoprim-sulfamethoxazole prophylaxis and various immune status parameters of the patient are other associated risk factors. The mortality of toxoplasma disease-eg, with organ involvement-can be particularly high in this setting. We have developed guidelines for managing toxoplasmosis in haematology patients, through a literature review and consultation with experts. In allogeneic HSCT recipients seropositive for Toxoplasma gondii before transplant, because T gondii infection mostly precedes toxoplasma disease, we propose weekly blood screening by use of quantitative PCR (qPCR) to identify infection early as a pre-emptive strategy. As trimethoprim-sulfamethoxazole prophylaxis might fail, prophylaxis and qPCR screening should be combined. However, PCR in blood can be negative even in toxoplasma disease. The duration of prophylaxis should be a least 6 months and extended during treatment-induced immunosuppression or severe CD4 lymphopenia. If a positive qPCR test occurs, treatment with trimethoprim-sulfamethoxazole, pyrimethamine-sulfadiazine, or pyrimethamine-clindamycin should be started, and a new sample taken. If the second qPCR test is negative, clinical judgement is recommended to either continue or stop therapy and restart prophylaxis. Therapy must be continued until a minimum of two negative PCRs for infection, or for at least 6 weeks for disease. The pre-emptive approach is not indicated in seronegative HSCT recipients, after autologous transplantation, or in non-transplant haematology patients, but PCR should be performed with a high level of clinical suspicion.

[Use of LDBIO Diagnostics® TOXOPLASMA ICT IGG-IGM in association with Siemens Atellica® IM in toxoplasmosis serological screening]

According to French recommendations for serological screening of toxoplasmosis, some profiles must be confirmed by additional methods, extending the time taken to produce results. Thus, the Laborizon Bretagne technical platform in Nantes studied the place of the LDBIO Diagnostics® TOXOPLASMA ICT IGG-IGM (ICT) test in addition to Siemens Atellica® serology. IgG-/IgM+ and equivocal or weak positive IgG/IgM- (IgGEq/IgM-) profiles on Atellica® will be confirmed by ICT, Alinity® Abbott and Platelia® Biorad. Among the 66 IgGEq/IgM- profiles, the concordance is perfect between ICT and complementary techniques: 21 weak positives were confirmed positive, 8 equivocal were considered negative and 37 were confirmed positive. Concerning the 76 IgG-/IgM+ profiles, 68 are negative and 7 are positive by complementary techniques and ICT. One discordance was observed. The Atellica®/ICT combination allows excellent discrimination of IgG-/IgM+ and IgGEq/IgM serological profiles with consistent diagnostic orientation in 99.3% of cases. Only 1 sample was found to be discordant but required monitoring at 15 days. The observed performances are compatible with routine use. This test simplifies the analytical process, improves the time to obtain results, while guaranteeing an excellent level of quality.

Carbon nanospheres dual spectral-overlapped fluorescence quenching lateral flow immunoassay for rapid diagnosis of toxoplasmosis in humans

Toxoplasmosis is a common zoonotic disease caused by a protozoan parasite Toxoplasma gondii (Tox), approximately infecting one-third of human populations worldwide. This study developed the carbon nanospheres (CNPs) based dual spectral-overlapped fluorescence quenching lateral flow immunoassay (CNPs-FQLFIA) for detection of Tox antibodies (ToxAbs). The CNPs have been effectively coupled with Tox antigen (ToxAg), which can completely overlap the excitation and emission spectra of europium nanospheres (EuNPs) and CdSe/ZnS quantum dots (QDs) in testing strips of CNPs-QDs-FQLFIA or CNPs-EuNPs-FQLFIA. The sensitivity of CNPs-EuNPs-FQLFIA or CNPs-QDs-FQLFIA was 4 or 8 IU/mL under natural light readout, or both 4 IU/mL ToxAbs under ultraviolet (UV) light readout by the naked eyes, respectively. The limit of detection (LOD) of two types of CNPs-FQLFIA was both 1 IU/mL ToxAbs under UV light by a dry fluorescence analyzer, but no cross-reaction was found with other antibodies. The intra-assay coefficient variation (CV) of both CNPs-EuNPs-FQLFIA and CNPs-QDs-FQLFIA was less than 8%, while the inter-assay CV was less than 14%, respectively. The correlation coefficient (R2) of CNPs-EuNPs-FQLFIA or CNPs-QDs-FQLFIA to measure the different concentrations of ToxAbs spiked serum samples was 0.99712 and 0.99896, respectively. The CNPs-FQLFIA presented a characteristics of 94.3% sensitivity, 100% specificity and 98% accuracy for detection of ToxAbs in clinical serum samples. In conclusion, CNPs-FQLFIA with EuNPs or QDs fluorescence reporter was an easy, rapid, sensitive, precise and quantitative assay for detecting Tox antibodies in human blood samples.

Multicenter evaluation of the Toxoplasma gondii Real-TM (Sacace) kit performance for the molecular diagnosis of toxoplasmosis

The molecular detection of Toxoplasma gondii DNA is a key tool for the diagnosis of disseminated and congenital toxoplasmosis. This multicentric study from the Molecular Biology Pole of the French National Reference Center for toxoplasmosis aimed to evaluate Toxoplasma gondii Real-TM PCR kit (Sacace). The study compared the analytical and clinical performances of this PCR assay with the reference PCRs used in proficient laboratories. PCR efficiencies varied from 90% to 112%; linearity zone extended over four log units (R2 > 0.99) and limit of detection varied from 0.01 to ≤1 Tg/mL depending on the center. Determined on 173 cryopreserved DNAs from a large range of clinical specimens, clinical sensitivity was 100% [106/106; 95 confidence interval (CI): 96.5%-100%] and specificity was 100% (67/67; 95 CI: 94.6%-100%). The study revealed two potential limitations of the Sacace PCR assay: the first was the inconsistency of the internal control (IC) when added to the PCR mixture. This point was not found under routine conditions when the IC was added during the extraction step. The second is a lack of practicality, as the mixture is distributed over several vials, requiring numerous pipetting operations. Overall, this study provides useful information for the molecular diagnosis of toxoplasmosis; the analytical and clinical performances of the Sacace PCR kit were satisfactory, the kit having sensitivity and specificity similar to those of expert center methods and being able to detect low parasite loads, at levels where multiplicative analysis gives inconsistently positive results. Finally, the study recommends multiplicative analysis in particular for amniotic fluids, aqueous humor, and other single specimens.

A Diagnostic Challenge: Toxoplasmosis Masquerading as Tonsillar Neoplasm

This case report elucidates an uncommon manifestation of toxoplasmosis characterized by an ulcerative oropharyngeal lesion and cervical lymphadenopathy, which intriguingly simulated a tonsillar neoplasm. The patient, a 28-year-old immunocompetent woman, reported symptoms such as a persistent sore throat, unilateral neck pain, and otalgia. Despite the initial clinical impressions, a diagnostic left subtotal tonsillectomy revealed no malignancy but marked acute and chronic inflammation. A comprehensive investigation subsequently indicated a recent primary infection with Toxoplasma gondii, as evidenced by the presence of high IgM antibodies and low IgG avidity. This unique case underlines the significance of incorporating toxoplasmosis into the differential diagnosis of oropharyngeal lesions, thereby necessitating a meticulous approach to laboratory testing. Laryngoscope, 134:1741-1743, 2024.

Application of gold immunochromatographic assay strip combined with digital evaluation for early detection of Toxoplasma gondii infection in multiple species

BACKGROUND

Timely diagnosis of Toxoplasma gondii infection is necessary to prevent and control toxoplasmosis transmission. The gold immunochromatographic assay (GICA) is a means of rapidly detecting pathogen in samples. GICA-based diagnostic methods have been developed to accurately detect pathogens with high sensitivity and specificity, and their application in T. gondii diagnosis is expected to yield good results.

METHODS

Colloidal gold test strips were produced using T. gondii C-terminal truncated apical membrane antigen 1 (AMA1C). Colloidal gold-AMA1C and colloidal gold-murine protein conjugate were synthesized under optimal conditions. A nitrocellulose membrane was treated with AMA1C and goat anti-mouse antibody as the test line and control line, respectively. In total, 90 cat serum samples were tested using AMA1C-GICA and a commercial enzyme linked immunosorbent assay (ELISA) kit. The GICA results were digitally displayed using a portable colloidal gold immunochromatographic test strip analyzer (HMREADER). The sensitivity, specificity, and stability of AMA1C-GICA were assessed, and this was then used to examine clinical samples, including 203 human sera, 266 cat sera, and 81 dog sera.

RESULTS

AMA1C-GICA had a detection threshold of 1:32 for T. gondii-positive serum. The GICA strips specifically detected T. gondii antibodies and exhibited no reactivity with Plasmodium vivax, Paragonimus kellicotti, Schistosoma japonicum, Clonorchis sinensis, and Schistosoma mansoni. Consequently, 15 (16.7%) positive samples were detected using the AMA1C-GICA and commercial ELISA kits for each of the assays. The receiver-operating characteristic curve showed that GICA had a relative sensitivity of 85.3% and specificity of 92%, with an area under the curve of 98%. After analyzing clinical samples using HMREADER, 1.2%-23.4% of these samples were found to be positive for T. gondii.

CONCLUSIONS

This study presents a novel assay that enables timely and efficient detection of serum antibodies against T. gondii, thereby allowing for its early clinical diagnosis. Furthermore, the integration of digital detection using HMREADER can enhance the implementation of GICA.

Could PLATELIA Toxo IgM be the new gold standard for the serological diagnosis of congenital toxoplasmosis: a French multicenter study

To assess the performance of PLATELIA Toxo IgM (Bio-Rad) and Toxo ISAGA (BioMérieux) to detect anti-Toxoplasma IgM in infants at risk of congenital toxoplasmosis, a retrospective multicenter study was conducted comparing serological results obtained in the framework of routine diagnosis work-up for congenital toxoplasmosis. All infants born to mothers infected with T. gondii during pregnancy from 2010 to 2020 with at least 6 months of serological follow-up were included (n = 1,010). One thousand ten cases were included, of which 250 infants (24.75%) had congenital toxoplasmosis. A total of 1039 sera were included. The concordance between the two techniques was 96%, with kappa coefficient of 0.87, showing an almost perfect agreement between ISAGA and PLATELIA. Cumulative sensitivity and specificity were 73.2% and 99.5.% and 74.8% and 100% for ISAGA and PLATELIA, respectively. The mean time to detect IgM using ISAGA and PLATELIA tests was 6.9 ± 20.1 days and 5.6 ± 14.7 days, respectively not significant (ns). Finally, the sensitivity of ISAGA and PLATELIA to detect IgM antibodies in infected neonates at 5 days of life was 62% and 64%, respectively. Performances of PLATELIA Toxo IgM assay were comparable to the gold standard ISAGA. This enzyme-linked immunosorbent assay is suitable for routine serology for the diagnosis of congenital toxoplasmosis in newborns. IMPORTANCE This study will help clinical microbiologists to chose an alternative serological method for the neonatal diagnosis of congenital toxoplasmosis, once the gold standard technique ISAGA will be withdrawn next year.

Comparative performance of ISAGA IgM and ELISA assays for the diagnosis of maternal and congenital Toxoplasma infections: which technique could replace ISAGA IgM?

The ISAGA immunocapture test for the detection of anti-Toxoplasma immunoglobulin M is a manual technique known for its excellent sensitivity and specificity. The purpose of this retrospective, multicenter study was to compare the performances and agreement between ISAGA and other IgM detection techniques before cessation of ISAGA production. The analytic performance of the different tests was evaluated using 1,341 serum samples from adults with positive IgM and negative IgG to Toxoplasma gondii, and 1,206 sera from neonates born to mothers with seroconversion. The agreement between the tests was evaluated on 13,506 adult and 5,795 child serum samples. The sensitivity of Toxo-ISAGA IgM® (adults 98.7%, neonates 63.1%) was similar to that of Platelia Toxo IgM® (adults 94.4%, neonates 64.6%), and significantly higher than Liaison Toxo IgM® (adults 90.6%), Architect/Alinity Toxo IgM® (adults 95.7%, neonates 48.6%), and Vidas Toxo IgM® (adults 81.8%, neonates 17.5%). However, the specificities varied between 24.4% (Platelia Toxo IgM®) and 95.2% (Liaison Toxo IgM®) in adults and were >95% for all tests in neonates. An analysis of the kappa coefficients showed better agreement between ISAGA IgM® and the other tests in children (0.75-0.83%) than in adults (0.11-0.53%). We conclude that, in the absence of Toxo-ISAGA IgM®, the association of a very sensitive technique (Platelia Toxo IgM® or Architect/Alinity Toxo IgM®) and a very specific technique (Vidas Toxo IgM® or Liaison Toxo IgM®) is recommended for IgM detection in adult sera. For neonates, Platelia Toxo IgM® appeared to be the best alternative to replace Toxo-ISAGA IgM®.

Genetic diversity and seroprevalence of Toxoplasma gondii in COVID‑19 patients; a first case-control study in Iran

BACKGROUND

Toxoplasmosis is a serious or life-threatening disease in immunosuppressed patients and pregnant women. This study examined the likely association between Toxoplasma gondii infection and COVID-19 patients with moderate illness.

METHODS

Seventy blood samples were collected from patients at the Health Reference Laboratory of Tabriz, Northwest Iran from April 2021 to September 2021. In addition, 70 healthy subjects of the same age (37 ± 15 years) and sex distribution were ethnically matched. Sera samples were examined for the detection of anti-Toxoplasma antibodies using ELISA. Nested-PCR targets were amplified based on the B1 and GRA6 genes. GRA6 amplicons were subjected to sequencing and phylogenetic analysis.

RESULTS

The seroprevalence of toxoplasmosis based on IgG titer was 35.7% in the COVID‑19 patients and 27.1% in the control group, representing not to be associated with the Toxoplasma seropositivity in COVID‑19 patients (P = 0.18) compared to healthy subjects. Anti-T. gondii IgM was not found in any of the patients and healthy individuals. According to PCR amplification of the B1 and GRA6 genes, the frequency of T. gondii in COVID-19 patients was 14.2% (10/70). However, no T. gondii infection was detected in the healthy group. The CD4+T cell count was relatively lower in toxoplasmosis-infected patients (430-450 cells/mm3) than in control group (500-1500 cells/mm3). High genetic diversity (Hd: 0.710) of the type I strain of T. gondii was characterized in the patients. Present results showed that consumption of raw vegetables and close contact with stray cats can increase the transmission of T. gondii to COVID-19 patients (P < 0.01).

CONCLUSIONS

The current study revealed that T. gondii type I infection is unequivocally circulating among the COVID-19 patients in Tabriz; However, no significant association was observed between the occurrence of Toxoplasma and the severity of COVID-19. To make more accurate health decisions, multicenter investigations with a larger sample size of different ethnic groups of the Iranian population are needed.

Pre-Transplant Seroprevalence, Associated Factors, and Post-Transplant Incidence of Toxoplasma gondii Infection Among Heart Transplant Recipients in Japan

BACKGROUND

Among solid organ transplant (SOT) recipients, heart transplant (HT) recipients are at a higher risk of Toxoplasma gondii infection. As Toxoplasma seroprevalence varies by geographic location, updated local epidemiology is essential to guide preventive and therapeutic strategies. However, the Toxoplasma seroprevalence and incidence of post-transplant toxoplasmosis among SOT recipients in Japan are unknown.

METHODS

We performed a single-center retrospective observational study at an HT center in Tokyo, Japan. All HT recipients aged ≥18 years between 2006 and April 2019 were included. We reviewed patient charts and conducted a questionnaire survey to investigate the risk factors for infection.

RESULTS

Among 105 recipients included in the study, 11 (10.5%) were seropositive before transplant. Ninety-five recipients (90.5%), including all pre-transplant seropositive recipients, answered the questionnaire. The recipients who had lived in Okinawa (odds ratio [OR] 7.5 [95% CI 1.42-39.61]; P = .032) and who reported raw-meat eating habits (OR 4.64 [95% CI 1.04-23.3]; P = .021) were more likely to be seropositive. None of the patients developed symptoms of toxoplasmosis. The post-transplant incidence of other major adverse outcomes was not significantly different according to the pre-transplant serostatus.

CONCLUSIONS

About 10% of HT recipients at an HT center in Tokyo were seropositive for Toxoplasma pre-transplant, and none developed symptomatic toxoplasmosis post-transplant on trimethoprim-sulfamethoxazole. The history of raw meat consumption was associated with seropositivity; therefore, avoiding it might be recommended for HT recipient candidates.

Comparison of B1 and RE 529 gene targets by real time PCR and LAMP assay for diagnosis of toxoplasmosis in pregnant females

PURPOSE

The aim of this study is to accurately diagnose the presence of toxoplasmosis in pregnant women. In this study we evaluated two gene targets B1 and RE-529 using two different molecular methods i.e., real-time PCR and LAMP.

PROCEDURE

A total of 150 blood samples were collected from pregnant women attending the PGIMER outpatient clinic. The serum and Buffy layer were extracted and various serological (ELISA) and molecular tests (qPCR and LAMP) targeting B1 and RE-529 were carried out.

FINDING

Out of 150 patients, 32 were seropositive. Amongst which for the RE-529 gene, 18 were LAMP positive and 16 were qPCR positive, while for the B1 gene, 14 were LAMP positive and 13 were qPCR positive.

CONCLUSIONS

Molecular methods were more sensitive than serological tests to diagnose congenital toxoplasmosis in antenatal females. Few seronegative patients were reported positive using molecular methods. In addition, LAMP targeting the RE-529 gene is more sensitive than qPCR, and LAMP targets the B1 gene.

TORCH Infections

Perinatal and neonatal infections are a significant cause of morbidity and mortality. As such, early recognition and workup when there is clinical concern is essential to supporting affected neonates. This article aims to focus specifically on the effects of toxoplasmosis, rubella, cytomegalovirus, herpes, and other agents (TORCH) infections, discussing epidemiology, diagnostics, and treatment if available. [Pediatr Ann. 2023;52(11):e400-e406.].

Identification of specific antigens between Toxoplasma gondii and Neospora caninum and application of potential diagnostic antigen TgGRA54

Toxoplasma gondii is a zoonotic parasite that is very common in livestock. Meat products from livestock infected with T. gondii are one of the important transmission routes of toxoplasmosis. Rapid and reliable diagnosis is a prerequisite for the prevention and control of toxoplasmosis. Neospora caninum and T. gondii are similar in morphology and life history, and there are a large number of cross antigens between them, making clinical diagnosis of toxoplasmosis more difficult. In this study, immunoprecipitation-mass spectrometry (IP-MS) was used to screen for T. gondii-specific antigens, and the specific antigen was cloned and expressed in Escherichia coli. The specific antigen was then used to establish an indirect ELISA diagnostic method. A total of 241 specific antigens of T. gondii and 662 cross antigens between T. gondii and N. caninum were screened by IP-MS. Through bioinformatics analysis and homology comparison, seven proteins were selected for gene cloning and prokaryotic expression, and the most suitable antigen, TgGRA54, was selected to establish an indirect ELISA for T. gondii. Compared with the indirect immunofluorescent antibody test (IFAT), the positive coincidence rate of the ELISA based on rTgGRA54 was 100% (72/72) and the negative coincidence rate was 80.95% (17/21). The indirect ELISA method based on TgGRA54 recombinant protein was established to detect T. gondii antibodies in bovine sera, and the recombinant protein reacted well with T. gondii positive sera from sheep, mouse, and swine, indicating that the recombinant protein is a good diagnostic antigen for T. gondii.

The detection of Toxoplasma gondii ME49 infections in BALB/c mice using various techniques

Toxoplasma gondii infections are primarily diagnosed by serological assays, whereas molecular and fluorescence-based techniques are garnering attention for their high sensitivity in detecting these infections. Nevertheless, each detection method has its limitations. The toxoplasmosis detection capabilities of most of the currently available methods have not been evaluated under identical experimental conditions. This study aimed to assess the diagnostic potential of enzyme-linked immunosorbent assay (ELISA), real-time polymerase chain reaction (RT-PCR), immunohistochemistry (IHC), and immunofluorescence (IF) in BALB/c mice experimentally infected with various doses of T. gondii ME49. The detection of toxoplasmosis from sera and brain tissues was markedly enhanced in mice subjected to high infection doses (200 and 300 cysts) compared to those subjected to lower doses (10 and 50 cysts) for all the detection methods. Additionally, increased B1 gene expression levels and cyst sizes were observed in the brain tissues of the mice. Importantly, IHC, IF, and ELISA, but not RT-PCR, successfully detected T. gondii infections at the lowest infection dose (10 cysts) in the brain. These findings may prove beneficial while designing experimental methodologies for detecting T. gondii infections in mice.

Past and present seroprevalence and disease burden estimates of Toxoplasma gondii infections in Germany: An appreciation of the role of serodiagnostics

Toxoplasmosis is one of the major foodborne parasitic diseases in Germany, with 49% of its population chronically infected with its causative agent, Toxoplasma gondii. Although the acute disease is usually benign in immunocompetent individuals, it is a threat for immunocompromised patients as well as for fetuses of seronegative mothers. As a result of infection, congenital and ocular toxoplasmosis can have serious lifelong consequences. Here I will highlight the epidemiologic situation, from its past in the two separate parts of Germany, to its unification 30 years ago and up to the present day. The main identified risk factor for infection in Germany is thought to be the consumption of undercooked or raw meat or sausages. However, the relative impact of this risky eating habit as well as that of other risk factors are changing and are discussed and compared to the situation in the Netherlands. Finally, the importance of robust and efficient high-throughput serological assays for obtaining reliable epidemiological data, on which public health decisions can be made, is highlighted. The potential of bead-based multiplex assays, which allow the incorporation of multiple antigens with different analytical properties and thus yield additional information, are described in this context. It illustrates the interdependence of new analytic assay developments and sound epidemiology, a foundation that decades-old data from Germany did not have.

Tissue cysts and serological detection toxoplasmosis among wild rats from Surabaya, East Java, Indonesia

Background

The protozoan Toxoplasma gondii is the source of zoonosis toxoplasmosis and causes public health problems throughout the world. Environmental contamination by oocysts excreted by cats as definitive hosts affects the spread of this disease. Wild rats as rodents can be used as an indicator of environmental contamination by oocysts, considering that rats have a habit of living in dirty environments and can be infected by oocysts from the environment.

Aim

This study aims to detect toxoplasmosis from tissue cysts and serological tests in wild rats as an indicator of environmental contamination in Surabaya.

Methods

A total of 100 wild rats collected from Surabaya were collected in five areas (West, East, Central, North, and South of Surabaya) obtained from three trapping locations: housing, dense settlements, and markets. All samples were examined microscopically for parasitological tests through the brain tissue samples, and the serum was examined using the toxoplasma modified agglutination test to detect the presence of IgG and Immunoglobulin M (IgM).

Results

This research used 100 wild rat samples, 77 Rattus tanezumi and 33 Rattus norvegicus, with evidence of 31% in serology and active infection with 19% tissue cyst. The results showed that the seroprevalence of T. gondii in wild rats was 31% (30% for IgG and 1% for IgM). Tissue cysts in the rat brain samples tested were 19% (19/100). The IgG prevalence rate in female rats was 25% (8/32), while for males, it was 32.3% (22/68). The highest seropositive IgG from densely populated settlements was 50%, markets were 25.8%, and housing was 12.1%. The highest seropositive IgM from densely populated settlements was 2.8%. Population density and the presence of cats are factors supporting the high seropositive rate at the trapping location.

Conclusion

This study revealed that there has been toxoplasmosis contamination in Surabaya with evidence of 31% in serology and active infection with 19% tissue cyst. It is necessary for controlling with surveillance in cats to prevent transmission in humans.

Is Childhood Immune Thrombocytopenia Associated With Acquired Toxoplasmosis? An Unusual Case of Infection That Led to Acute ITP in a Greek Male Toddler and Implications for Guidelines

INTRODUCTION

Childhood immune thrombocytopenic purpura (ITP) is a heterogeneous immune-mediated process triggered by infections, vaccines, allergies and parasites. Currently, there is little evidence in the literature beyond case reports of an association with Toxoplasma gondii (T. gondii).

METHODS

The authors describe the unusual case of an earlier healthy 2.5-year-old Greek boy who developed acute ITP with a life-threatening platelet count a few days after a T. gondii infection. Evidence for the infection onset was found incidentally 3 months after the initial admission to the hospital and only after any other plausible cause of thrombocytopenia was excluded, according to diagnosis guidelines.

RESULTS

The boy underwent 3 intravenous immunoglobulin treatments within a trimester, a period during which his alarming platelets count levels led to housebound activities. A quite slow recovery was only ignited after the third treatment, which was administered in conjunction with a mild antibiotic medication for the T. gondii infection. Full recovery was obtained 9 months after the initial admission, although the boy's potential scored high in clinical prediction models for developing transient ITP.

CONCLUSION

There is a need for more research on ITPs with no obvious cause to investigate a causal association with toxoplasmosis. Currently, testing for diseases of greater rarity and of higher diagnostic cost than T. gondii is included in the ITP guidelines. Hence, routinely testing for toxoplasmosis when considering potential childhood ITP triggers and infection treatment complementary to treating the ITP might be the key to accelerating the healing process and improving the quality of life of otherwise confined children.

Seroepidemiology of toxoplasmosis in pregnant women and detection of infection acquired during pregnancy in Cotonou, Benin

Assessing the prevalence of toxoplasmosis in pregnant women and the associated risk factors is the first step in defining policy for the prevention of congenital toxoplasmosis in a given population. An epidemiological study was conducted during prenatal consultations at the CHU-MEL of Cotonou (Benin) between September 2018 and April 2021 and recruited 549 pregnant women to determine the seroprevalence and potential factors associated with Toxoplasma gondii infection. Toxoplasma gondii IgG/IgM antibodies were detected using an enzyme-linked fluorescence assay (ELFA) technique, an IgG avidity test and an IgG/IgM comparative Western blot to diagnose the maternal toxoplasmosis serological status, the possibility of an infection acquired during pregnancy and congenital infection, respectively. Concomitantly, the participants answered a questionnaire investigating potential risk factors. Toxoplasmosis seroprevalence was estimated at 44.4% (95% CI 40.3-48.6) and the factors significantly associated with T. gondii seropositivity were: age over 30 years, multigravid women and contact with cats. The possibility of an infection acquired during the periconceptional period or the first trimester of pregnancy concerned six women [1.1% (95% CI 0.5-2.0)]. However, due to the low rate of serological controls in seronegative women, a significant proportion of women first tested during the 3rd trimester of pregnancy, and an insufficient sample size, the incidence of primary infection during pregnancy could not be determined. No cases of congenital transmission occurred in the newborns from the suspected cases of primary infection.

Is Toxoplasma gondii infection a concern in individuals with rheumatic diseases? Evidence from a case-control study based on serological diagnosis

Toxoplasma gondii infection in clinical cases of rheumatic diseases is increasing, whereas, the relationship between T. gondii infection and rheumatic diseases is still ambiguous and contradictory. Thus, the present case-control study based on serological diagnosis was carried out to identify the underlying relationship between T. gondii infection and rheumatic diseases in China. Serological results showed that rheumatic patients (17.25%, 79/458) had a significantly higher T. gondii seroprevalence than control subjects (10.70%, 49/458) (p = 0.004). However, the difference in T. gondii seroprevalence among clinical rheumatic disease forms was insignificant. Moreover, disease duration not effect the T. gondii seroprevalence in the included clinical rheumatic patients. Three risk factors (presence of cats at home, blood transfusion history, and consumption of raw shellfish) were identified through multivariate analysis to affect the T. gondii seroprevalence in the included clinical rheumatic patients. In conclusion, these results indicate that the latent T. gondii infection in clinical rheumatic patients should cause alarm and attention in the course of future scientific research or clinical treatment.

Real-time PCR in the diagnosis of congenital toxoplasmosis

The diagnosis of congenital toxoplasmosis presents limitations and therefore new options are necessary. The analysis of amniotic fluid by real-time PCR has already proved effective for confirmation of fetal infection. However, its performance in other biological samples is not clear yet. The aim of this study is to better understand the role of real-time PCR in the blood of the mother and newborn as well as in the amniotic fluid and placenta in the diagnosis of congenital toxoplasmosis. This is a descriptive cohort study of pregnant women with toxoplasmosis followed up in Rio de Janeiro, Brazil. Real-time PCR was performed in samples of maternal blood, amniotic fluid, placenta, and blood of newborns. In addition, histopathological examination of placentas was performed, and data collected from babies were collected. 116 pregnant women were followed up and 298 samples were analyzed. One (0.9%) pregnant woman presented positive PCR in the blood, 3 (3.5%) in the amniotic fluid, 1 (2.3%) in the placenta and no newborn had positive PCR in the blood. Histopathological study was suggestive of toxoplasmosis infection in 24 (49%) placentas. Six (5.2%) newborns were diagnosed with congenital toxoplasmosis, and only cases with positive PCR in the amniotic fluid had correlation of the PCR result with the diagnosis of congenital infection. Both maternal and blood samples of newborns and placenta did not prove to be promising in the diagnosis of congenital toxoplasmosis. Further studies are needed to evaluate the real role of molecular diagnosis in other biological materials rather than the amniotic fluid.

Prevalence of preconception TORCH infections and its influential factors: evidence from over 2 million women with fertility desire in southern China

BACKGROUND

TORCH (Toxoplasma gondii [TOX], Cytomegalovirus [CMV], Rubella virus [RV], and Herpes simplex virus [HSV]) represents pathogens known to traverse the maternal-fetal barrier and cause severe neonatal anomalies. We aimed to assess the prevalence of preconception TOX, CMV, and RV infections among women with fertility desire in southern China, and identify related risk factors.

METHODS

Data were obtained from a population-based cross-sectional study conducted as part of the National Free Preconception Health Examination Project. Women planning to conceive within the next 6 months in Guangdong Province were enrolled between 2014 and 2019. Information on sociodemographic, gynecological, and obstetric characteristics was collected. Sera were analyzed for TOX IgG, CMV IgG, and RV IgG antibodies using an enzyme-linked immunosorbent assay. Descriptive, univariate, and multivariate logistic regression analyses were performed to assess the association between TORCH infections and related factors.

RESULTS

Among 2,409,137 participants, the prevalence of IgG antibodies for TOX, CMV, and RV was 3.20% (95% CI: 3.18-3.22%), 77.67% (95% CI: 77.62-77.71%) and 76.03% (95% CI: 75.98-76.07%), respectively. Of all participants, 141,047 women (5.85%, 95% CI:5.83-5.88%) reported a history of immunization for RV. Women living in the Pearl River Delta, a more developed region, have significantly lower vaccination rates than those living in other regions. The seropositivity of TOX IgG was highest among women aged 35 years and above, with primary or lower education levels, and rural registration. Factors such as being older, having a higher educational level, and being of other ethnicities were associated with a higher prevalence of naturally acquired CMV and RV infections. Women living in the Pearl River Delta showed a higher risk of TOX, CMV, and RV infections, with aORs of 2.21, 4.45, and 1.76, respectively. A history of pregnancy, gynecological diseases, and sexually transmitted infections were potentially associated with TORCH infections, but this association varied across pathogens.

CONCLUSION

The findings of this study update the baseline of preconception TORCH infections among women with fertility desire in southern China, helping to estimate the risk of congenital infection and guide the development and implementation of effective prevention measures for preconception TORCH infections.

Evaluation of Toxoplasma gondii IgG avidity assays through a comparison of IgM serostatus

Primary Toxoplasma gondii (T. gondii) infection during pregnancy could result in congenital disease with severe clinical complications. IgM antibodies are one of the indices of primary infection. The IgG avidity index (AI) is also known to remain low for at least 3 months after primary infection. Here, we evaluated and compared the performance of T. gondii IgG avidity assays as confirmed by T. gondii IgM serostatus and number of days post-exposure. Four assays preferentially used in Japan were employed to measure the T. gondii IgG AI. Results for the T. gondii IgG AI showed good concordance, particularly in cases with a low IgG AI. This study confirms that the combination of T. gondii IgM and IgG AI tests is a reliable and suitable method for identifying T. gondii primary infections. Our study proposes the necessity of measuring the T. gondii IgG AI as an additional indicator of T. gondii primary infection.

[Overview of infectious and non-infectious diseases in French Guiana in 2022]

Source of many myths, French Guiana represents an exceptional territory due to the richness of its biodiversity and the variety of its communities. The only European territory in Amazonia, surrounded by the Brazilian giant and the little-known Suriname, Ariane 6 rockets are launched from Kourou while 50% of the population lives below the poverty line. This paradoxical situation is a source of health problems specific to this territory, whether they be infectious diseases with unknown germs, intoxications or chronic pathologies.Some infectious diseases such as Q fever, toxoplasmosis, cryptococcosis or HIV infection are in common with temperate countries, but present specificities leading to sometimes different management and medical reasoning. In addition to these pathologies, many tropical diseases are present in an endemic and / or epidemic mode such as malaria, leishmaniasis, Chagas disease, histoplasmosis or dengue. Besides, Amazonian dermatology is extremely varied, ranging from rare but serious pathologies (Buruli ulcer, leprosy) to others which are frequent and benign such as agouti lice (mites of the family Trombiculidae) or papillonitis. Envenomations by wild fauna are not rare, and deserve an appropriate management of the incriminated taxon. Obstetrical, cardiovascular and metabolic cosmopolitan pathologies sometimes take on a particular dimension in French Guiana that must be taken into account in the management of patients. Finally, different types of intoxication are to be known by practitioners, especially due to heavy metals.European-level resources offer diagnostic and therapeutic possibilities that do not exist in the surrounding countries and regions, thus allowing the management of diseases that are not well known elsewhere.Thanks to these same European-level resources, research in Guyana occupies a key place within the Amazon region, despite a smaller population than in the surrounding countries. Thus, certain pathologies such as histoplasmosis of the immunocompromised patient, Amazonian toxoplasmosis or Q fever are hardly described in neighboring countries, probably due to under-diagnosis linked to more limited resources. French Guiana plays a leading role in the study of these diseases.The objective of this overview is to guide health care providers coming to or practicing in French Guiana in their daily practice, but also practitioners taking care of people returning from French Guiana.

Comparison of Toxoplasmosis in Narcotic Drug-addicted and Healthy Persons in the Southwest of Iran; A Case-control Study

INTRODUCTION

Toxoplasmosis and narcotic drug addiction are endemic in various regions of Iran. These drugs can provide situations for infections by disrupting the immune system. The current case-control study was designed to determine the prevalence of toxoplasmosis in narcotic drugaddicted persons in comparison with healthy subjects using serology and molecular techniques in the southwest of Iran.

METHODS

A total of 201 subjects (including 101 individuals with drug addiction and 100 control participants) were randomly selected. Chronic and acute toxoplasmosis was detected using the enzymelinked immunosorbent assay (ELISA) IgG avidity. T. gondii immunoglobulin G (IgG) and immunoglobulin M (IgM) were also determined by the ELISA. Moreover, the presence of T. gondii in blood samples was diagnosed using the nested-polymerase chain reaction (Nested-PCR).

RESULTS

For T. gondii IgG, 17 (17.0%) of 100 and 39 (38.6%) of 101 cases were diagnosed in the control participants and drug-addicted people, respectively [P=0.001, OR=3.071, CI= (1.591-5.929)]. Moreover, 16 (15.8) and 5 (5.0%) cases were positive for the B1 gene in the drug-addicted patients and controls by the nested-PCR technique, respectively [P=0.019, OR=3.576, CI= (1.257-10.179)]. However, no significant differences were found between the opium (n=64) and crystal methamphetamine (n=37) groups in terms of T. gondii IgG and IgM antibodies and the presence of the parasite in the blood (P>0.05).

CONCLUSION

The present results demonstrated that the outbreak of the infection was more frequent in narcotic drug-addicted persons than the controls using serology and molecular techniques.

Aicardi-Goutières syndrome (AGS): recurrent fetal cardiomyopathy and pseudo-TORCH syndrome

Aicardi-Goutières syndrome (AGS) induces innate immune activation. It can present with cerebral calcifications and hepatosplenomegaly mimicking congenital infections. The present case report discusses the diagnosis and treatment of a case of fetal cardiomyopathy whose postnatal symptoms resembled TORCH (toxoplasmosis, other agents, rubella, cytomegalovirus, herpes and syphilis) infection. The mother had a history of two lost pregnancies due to fetal cardiomyopathy and the same was identified in the current pregnancy. At 34 weeks of gestation, the mother delivered a late preterm male neonate due to intrauterine growth restriction weighing 1590 g with respiratory distress and cardiomyopathy at birth. The neonate had cerebral calcifications, hepatosplenomegaly and thrombocytopenia. As the infant's TORCH IgM titre was negative, pseudo-TORCH syndrome similar to AGS was suspected. Clinical exome sequencing of the parents and fetus identified no genes for hydrops fetalis or fetal cardiomyopathy; however, the AGS TREX1 gene was identified in the neonate, while additional symptoms resembled TORCH infection. The neonate was discharged and has shown improvement with oral baricitinib treatment for the last 9 months.

Prevention of congenital toxoplasmosis in France using prenatal screening: A decision-analytic economic model

Background

Toxoplasma gondii is one of the world’s most common parasites. Primary infection of the mother during pregnancy can lead to transmission to the fetus with risks of brain and eye lesions, which may cause lifelong disabilities. France instituted a national program based on monthly retesting of susceptible pregnant women to reduce the number of severe cases through prompt antenatal and postnatal treatment and follow-up.

Objective

To evaluate the ability of the French prenatal retesting program to reduce the lifetime costs of congenital toxoplasmosis.

Methods

We measured and then compared the costs and benefits of screening vs. not screening using decision-tree modelling. It included direct and indirect costs to society of treatment and care, and the lifetime lost earnings of children and caregivers. A probabilistic sensitivity analysis was carried out.

Findings

Total lifetime costs per live born child identified as congenitally infected were estimated to be €444 for those identified through prenatal screening vs €656 for those who were not screened. Estimates were robust to changes in all costs of diagnosis, treatment, and sequelae.

Interpretation

Screening for the prevention of the congenital T. gondii infection in France is cost saving at €212 per birth. Compared with no screening, screening every pregnant woman in France for toxoplasmosis in 2020 would have saved the country €148 million in addition to reducing or eliminating the devastating physical and emotional suffering caused by T. gondii. Our findings reinforce the conclusions of other decision-analytic modelling of prenatal toxoplasmosis screening.

Clinical validation of visual LAMP and qLAMP assays for the rapid detection of Toxoplasma gondii

Humans are exposed to Toxoplasma gondii infection as pet cats gradually become family members and represent an increasing public health risk worldwide. Toxoplasmosis diagnosis constitutes an important measure for disease prevention and control. In this study, real-time fluorescence quantitative loop-mediated isothermal amplification (qLAMP) and visual LAMP detection technologies were established to conduct tests of T. gondii based on the membrane DNA extraction method, and the optimal detection mix was determined by adding the protective reagent trehalose and screening the concentrations of Mg²⁺ and dNTPs. Paraffin and lyophilization were used to reduce and even remove aerosol pollution, constructing a detailed anti-contamination protocol. Based on the positive standard plasmid DNA, the LODs of qLAMP and visual LAMP were 92 copies/μL and 92 copies/μL, and the standard curve of qLAMP was Y=2.9503X+20.8992 with R^{2 =} 0.99. The applicability of the qLAMP and visual LAMP assays in disease diagnosis was assessed by evaluating 200 clinical cat faeces samples. The assays showed good diagnostic consistency, with kappa values of 1.0 and 0.99 compared with TaqMan qPCR, respectively. Compared with TaqMan qPCR, the diagnostic specificity/sensitivity of qLAMP and visual LAMP were 100%/100% and 100%/80%, respectively. The qLAMP and visual LAMP assays reported here are rapid and simple tests without extensive sample preparation and have a short turnaround time within 60 min, making them suitable for point-of-care testing.

Retrospective Evaluation of Toxoplasma Serology in Patients Admitted to a Training and Research Hospital Between 2017-2021

OBJECTIVE

In this study, it was aimed to retrospectively evaluate the anti-Toxoplasma IgG, IgM and avidity index results of patients who were requested for Toxoplasma serology in our hospital between 01.01.2017 and 31.12.2021.

METHODS

Anti-Toxoplasma antibodies are studied with Abbott Architect İ2000 SR device that using the chemiluminescent microparticle immunoassay method (CMIA), according to the company's recommendations. The age, gender, nationality, sending clinic/polyclinic, and pregnancy status information of patients were scanned from the hospital system.

RESULTS

In the five-year period between 2017 and 2021, 29.58% of anti-Toxoplasma IgG tests requested from 12694 patients and 0.94% of anti-Toxoplasma IgM tests sent from 12546 patients were found positive. It is striking that the number of test requests is higher in women. IgG positivity is highest in women in the age group of 30-39 (9.97%), and in men in the age group of 60-69 (6.97%). IgM positivity is higher in both women and men in the 20-29 age group (0.48% and 0.38%, respectively). Anti-Toxoplasma IgG was positive in 27.78% and IgM in 0.64% of the pregnant women. IgG positivity in Turkish and Syrian pregnant women were determined as 25.88%; 47.10% and IgM positivity as 0.49% and 1.83%, respectively, and the difference was statistically significant (p<0.001).

CONCLUSION

Our anti-Toxoplasma antibody positivity was found to be compatible with studies conducted in different centers in our country. The fact that IgM positivity in women is high in the 20-29 age group, which is the childbearing age, emphasizes the importance of screening before and during pregnancy. Consistent with other studies in the literature, the rate of seropositivity in Syrian pregnant women was found to be higher than Turkish. This is important in terms of showing the effect of socio-cultural behaviors on prevalence.

Can cloning and sequencing help to genotype positive Toxoplasma gondii clinical samples? Results and validation using SAG3 as a model

Genotyping of T. gondii in human cases is relevant to understand the transmission patterns and epidemiology of this parasitosis. However, this genetic characterization can be hampered by the difficulty of isolating the parasite from mild or asymptomatic cases and by the detection efficiency of molecular assays such as the multilocus nested-polymerase chain reaction-restriction fragment length polymorphism (Mn-PCR-RLFP). To propose an alternative for the genotyping of positive clinical samples of T. gondii with a low amount of the parasite DNA mixed within the host DNA or mixed infections, we carried out this study to validate the sequences of the SAG3 gene of T. gondii obtained after two rounds of amplification cloned into a bacterial model, thereby achieving the separation and identification of more than one genotype of T. gondii. Also, the detection limit of the parasite DNA and the fidelity of the reagents used in the nested PCR-RFLP in artificial clinical samples by sequencing were determined. T. gondii DNA was detected from 6.25 ng of DNA and 200 parasites/mL of blood. The fidelity of the AmpliTaq Gold™ polymerase after 65 cycles of amplification was 100%. Denaturation of the products obtained after two rounds of nested PCR amplification showed no evidence of chimera or artifact production. The cloning efficiency was 97.5% (39/40 clones), and none of the experiments produced recombinant sequences. Thus, the generation of chimeras with this methodology could be ruled out. Genotyping of clinical samples is important because there is no strain selection bias, as can occur in the bioassay (where more virulent strains can be selected over nonvirulent strains), and therefore, mixed infections can be detected through cloning and sequencing. Furthermore, these two techniques could be useful tools to genotype weak amplicons of any T. gondii gene obtained during nested PCR.

Development of a droplet digital polymerase chain reaction tool for the detection of Toxoplasma gondii in meat samples

Toxoplasmosis is a zoonotic disease caused by the protozoan parasite Toxoplasma gondii. Infection in humans has usually been related to the consumption of raw, undercooked or cured meat. The aim of this study was to develop a droplet digital polymerase chain reaction (ddPCR)-based assay for the detection and quantification of T. gondii in meat samples. To optimize the ddPCR, T.gondii reference DNA aliquots at five known concentrations: 8000 cg/µl, 800 cg/µl, 80 cg/µl, 8 cg/µl were used. Moreover, results obtained by ddPCR and quantitative PCR (qPCR) were compared using 80 known samples (40 positive and 40 negative), as well as 171 unknown diaphragm tissue samples collected at slaughterhouses. The ddPCR showed a sensitivity of 97.5% and a specificity of 100%, with a detection limit of 8 genomic copy/µl of T. gondii. A nearly perfect agreement (κ = 0.85) was found between results obtained by ddPCR and qPCR for both positive and negative known samples analysed. On the 171 diaphragm tissue samples from field, 7.6% resulted positive by ddPCR and only 1.2% by qPCR. Therefore, this innovative method could be very useful for the detection of T. gondii in meat samples, aiming to prevent human infections.

Unusual Toxoplasma infection of the eye and central nervous system in an HIV-positive patient

OBJECTIVE

To report on a unique combination of cerebral toxoplasmosis and ocular toxoplasmosis in an HIV-positive patient in Slovakia.

METHODS

A 35-year-old heterosexual patient who presented with headache and major seizures underwent computed tomography (CT) and magnetic resonance imaging (MRI). Based on clinical findings, serological tests for toxoplasmosis were performed on serum and ocular fluid specimens. PCR was also used to detect Toxoplasma gondii and cytomegalovirus DNA. Goldmann and Witmer coefficient calculation was applied to demonstrate the synthesis of intraocular IgG antibodies.

RESULTS

CT and MRI revealed cystic lesions suspected of metastasis in the occipital and temporal regions, and we searched for the primary tumor. After vision loss in the left eye, which rapidly progressed to complete blindness, an eye examination detected macular edema. Anti-edema treatment was initiated. HIV positivity with a very low CD4 T-cell count (20/&#956;L) was found, and the viral load was 100 400 HIV-RNA copies/ml. The serum was positive for anti-Toxoplasma IgG antibodies (&gt; 200 IU/mL), IgM negative, and IgA borderline. As toxoplasmic encephalitis and retinitis were suspected, antitoxoplasmic therapy with pyrimethamine, spiramycin, and folinic acid was started. The ophthalmologist considered cytomegalovirus retinitis, which was not confirmed by serology or PCR. In contrast, the presence of IgG antibodies in ocular fluid and serum with the calculation of the Goldmann-Witmer coefficient (GW = 32) as well as PCR DNA positivity pointed to Toxoplasma gondii as the etiological agent. Follow-up MRI scan confirmed regression of the pathological lesions, neurological deficit also improved, CD4 T-lymphocytes increased above 200/&#956;L, but blindness of the left eye persisted.

CONCLUSION

CT and MRI scans offered no clue as to Toxoplasma etiology of the brain and eye involvement in an HIV-positive patient, which was only confirmed by laboratory tests. Due to the delay in the diagnosis of toxoplasmosis, time from the epileptic seizure to treatment initiation was 16 days, which assumedly caused irreversible blindness in the patient.

Saliva and tear as useful tools for the diagnosis of Toxoplasma gondii in human specimens: a systematic review

Toxoplasmosis is diagnosed by serology, mainly using invasive specimens such as serum or cerebrospinal fluid. This study aimed to investigate whether saliva and tear samples can be used instead of serum samples to diagnose Toxoplasma gondii. Five English-language databases were checked up to 2021. Other types of non-invasive samples (milk and urine) were excluded from this study. In 15 cross-sectional studies, a total of 4338 saliva samples were examined, out of which 718/3848 (18.66%), 30/200 (15%), and 60/122 (49.18%) samples were positive for anti-T. gondii IgG, IgM, and IgA antibodies, respectively. And for tear samples, a total of 723 samples in cross-sectional studies and 153 cases and 97 controls in case-control studies were included, out of which 199/538 (36.98%) and 155/247 (62.75%) samples were positive for anti-T. gondii IgG and IgA antibodies in cross-sectional studies and 86/128 (67.18%), 1/53 (1.88%), and 78/153 (50.98%) cases and 4/47 (8.51%), 0/47 (0%), and 12/97 (12.37%) controls were positive for anti-T. gondii IgG, IgM, and IgA antibodies in case-control studies, respectively. The results suggested that antibody levels in saliva and tear samples in humans could be useful for the diagnosis of toxoplasmosis, especially ocular toxoplasmosis using tear samples.

Study of toxoplasmosis in type 2 diabetic patients using ELISA and B1 nested-PCR methods

Toxoplasma gondii (T. gondii) is a ubiquitous, opportunistic organism, which actually infects all warmblooded animals. Diabetes is a silent, irritating metabolic disorder among which type 2 diabetes includes over 90% of cases globally. This case-control study was aimed to detect T. gondii infection in type 2 diabetic patients in Khuzestan province, southwest of Iran. Serological enzyme-linked immunosorbent assay (ELISA) and molecular polymerase chain reaction (PCR) method targeting B1 gene were employed to comparatively detect the parasitic infection among 377 diabetic patients and 200 non-diabetic subjects during 2016-2018. Considerably higher anti-T. gondii antibodies were determined in case group 44.29% (167/377), than in control group 19% (38/200) (P<0.05). Among diabetic patients, 153 (40.58%) were seropositive for IgG and 14 (3.71%) were seropositive for IgM, while 35 (17.5%) and 3 (1.5%) healthy people were seropositive regarding IgG and IgM, respectively (P<0.05). By nested PCR, B1 gene was identified in 36 out of 167 (21.55%) and 5 out of 38 (13.15%) of the seropositive samples of case and control groups, respectively. The prevalence of anti-T. gondii antibodies and DNA in diabetic patients was significantly higher than in non-diabetic patients. Thus, it could be recommended to routinely evaluate the chronicity of the infection in diabetic patients.

Performance of immunochromatographic and immunoenzymatic techniques in the diagnosis of toxoplasmosis in pregnant women in Cameroon: need for harmonization

Introduction

in order to contribute to the improvement of the management of toxoplasmosis in pregnant women in Cameroon, performance of two techniques commonly used in the diagnosis of toxoplasmosis was evaluated.

Methods

a total of 541 pregnant women were recruited from seven hospitals in two Regions of Cameroon, of which 63% (341: Batch1) were from health facilities (HF) using a immunochromatographic technique (ICT) as a screening test for toxoplasmosis, and 37% (200: Batch2) from those using an immunoenzymatic technique (IEZ). On each sample, Ig (Immunoglobulin) G (IgG) and IgM were tested by three techniques: a Rapid Diagnostic Test (RDT), an Enzyme Linked Immuno Sorbent Assay (ELISA) and a Vidas Enzyme-linked fluorescent assay taken as reference (VIDAS/ELFA). The results from the health facilities were recorded.

Results

for the IgG assay, our two laboratory methods were sensitive (96.0% and 97.5%) and specific (64.2% and 59.7%). Their concordance rates with the VIDAS/ELFA reference were above 60% (P<0.001). Moreover, for the IgM assay, the performances of the two methods were equivalent: Se= 18.2%, Sp= 99.4% with a low concordance rate (Kappa = 0.24). Considering the results provided by the selected hospitals, the ELISA used in Batch2 showed similar performances to the two techniques used in reference lab while the performances were low for the RDT used in Batch1.

Conclusion

both methods showed similar performances (good for (IgG) and poor for IgM). However, for the immunochromatographic method, differences in performance were found between our results and those provided by the selected health facilities. These differences suggest a harmonization of diagnostic techniques for toxoplasmosis in pregnant women in Cameroonian health facilities.

Acute exacerbation of pulmonary toxoplasmosis during corticosteroid therapy for immune thrombocytopenia: A case report and literature review

RATIONALE

Pulmonary toxoplasmosis (PT) is an infectious disease that can be fatal if reactivation occurs in the recipients of hematopoietic stem cell transplantation (HSCT) who were previously infected with Toxoplasma gondii. However, whether the toxoplasmosis reactivation is an actual risk factor for patients receiving immunosuppressive therapies without HSCT remains unclear. Therefore, reactivated PT is not typically considered as a differential diagnosis for pneumonia other than in patients with HSCT or human immunodeficiency virus (HIV).

PATIENT CONCERNS

A 77-year-old man presented with fever and nonproductive cough for several days. He was hospitalized due to atypical pneumonia that worsened immediately despite antibiotic therapy. Before 4 months, he was diagnosed with immune thrombocytopenia (ITP) and received corticosteroid therapy. Trimethoprim-sulfamethoxazole (ST) was administered to prevent pneumocystis pneumonia resulting from corticosteroid therapy.

DIAGNOSIS

The serological and culture test results were negative for all pathogens except T. gondii immunoglobulin G antibody. Polymerase chain reaction, which can detect T. gondii from frozen bronchoalveolar lavage fluid, showed positive results. Therefore, he was diagnosed with PT.

INTERVENTION

ST, clindamycin, and azithromycin were administered. Pyrimethamine and sulfadiazine could not be administered because his general condition significantly worsened at the time of polymerase chain reaction (PCR) examination.

OUTCOMES

The patient died of acute respiratory distress syndrome despite anti-T. gondii treatment. An autopsy revealed a severe organizing pneumonia and a small area of bronchopneumonia.

LESSONS

PT should be considered as a differential diagnosis in patients with pneumonia, particularly in seropositive patients who receive immunosuppressive therapies even for other than HSCT or HIV.

Detection of Pneumocystis jirovecii and Toxoplasma gondii in patients with lung infections by a duplex qPCR assay

Pneumocystis pneumonia (PCP) and pulmonary toxoplasmosis (PT) are caused by Pneumocystis jirovecii and Toxoplasma gondii. The clinical symptoms and imaging of PCP and PT are indistinguishable. A duplex qPCR was developed to differentiate between these two pathogens. In testing 92 clinical samples to validate the performance of this method for P. jirovecii detection, it identified 31 positive samples for P. jirovecii infection, consistent with clinical diagnosis. Among the remainder of the 61 clinical samples with suspected PCP, yet showing as negative by the conventional PCR diagnosis approach, 6 of them proved positive using our new assay. Our new approach also produced similar results in identification of T. gondii infections, giving a result of 2 positive and 20 negative in clinical samples. An investigation was undertaken on the prevalence of P. jirovecii and T. gondii infections using 113 samples from lung infection patients. 9% (10/113) were shown to be positive with infections of P. jirovecii, 2% with T. gondii (2/113) and 5% (6/113) were co-infected with both pathogens. Although this duplex qPCR can detect individual P. jirovecii and T. gondii infection, and co-infection of both pathogens, further large-scale investigations are needed to validate its performance, especially in T. gondii detection. Our assay provides a rapid and accurate tool for PCP and PT diagnosis in immunocompromised population and clinical surveillance of these infections in patients with no immune defects.

Pneumocystis jirovecii and Toxoplasma gondii are opportunistic pathogens that can cause pneumocystis pneumonia (PCP) and pulmonary toxoplasmosis (PT) in immunocompromised patients. Due to the non-specific clinical symptoms and similar imaging of lung pathology, these two deadly diseases are difficult to be clinically differential diagnosed. Early diagnosis of these infections would reduce medical costs, morbidity and mortality. A duplex qPCR method was developed for the detection of both P. jirovecii and T. gondii infection simultaneously. This new assay provides a potential application for diagnosis and surveillance of both PCP and PT. Further investigation for the prevalence of P. jirovecii and T. gondii infections indicated that P. jirovecii and T. gondii involvement in lung infection has been seriously underestimated.

[Toxoplasmosis in Spain, analysis of hospitalizations during the period 1997-2018.]

OBJECTIVE

Toxoplasmosis is a systemic infectious disease. Infection is acquired by ingestion of Toxoplasma gondii cysts or by vertical transmission mother-to-child during pregnancy (congenital toxoplasmosis). In Spain, the prevalence shows wide variability depending on the region and the study. The incidence in other European countries evidences a decline in recent years. The aim of this study was to characterize the presence and the epidemiological patterns of the disease in the Spanish population with information obtained of hospitalized cases with a diagnosis of toxoplasmosis at discharge.

METHODS

The interactive platform of the Specialized Registry (RAE-MBD) of the Ministry of Health was used to obtain data on hospital discharges with "toxoplasmosis" diagnosis. Frequencies and rates of hospital discharges were calculated according to sex, age groups, region and diagnosis at discharge. Sequence graphs were generated to analysed the temporal evolution of the number of hospitalizations. The trends and slopes of the RHs were analyzed using "joinpoint" regression models, estimating the mean annual percentage change (PCAM) in the RHs and its 95% confidence interval.

RESULTS

There were 13,704 cases with toxoplasmosis diagnosis at discharge, (58%) were men. The highest hospitalization rate (RH) was in the 15-44-year-old men group (5,804 discharges and HT=2.52). During the period studied a decrease in the number of discharges was observed, it was progressive and affected all the autonomous regions, being more pronounced in men (81.9% vs 63.9%).

CONCLUSIONS

The number of hospitalizations in Spain decreased substantially during the studied period (1997-2018), similar to other European studies reported. The decrease was progressive and mainly affected men between 15-44 years.

Comparisons of Toxoplasma gondii Prevalence in Rural and Urban Areas of Al-Najaf Province of Iraq Using Serological Methods

Toxoplasma gondii (T. gondii) is an intracellular protozoan parasite that multiplies within the host cell and causes the disease toxoplasmosis. T. gondii is distributed worldwide and is capable of infecting almost all warm-blooded animals. The current study was conducted in several urban and rural regions in AL-Najaf province of Iraq from September 2020 to April 2021. In total, 190 blood samples were collected and screened for T. gondii IgG and IgM antibodies using Rapid Diagnostic immunochromatographic test and the enzyme-linked immunosorbent assay (ELISA). These two tests were performed on 5 ml of blood samples. The results of the ICT test showed that 80 (42.1%) samples were positive for IgG; however, no IgM positive sample was recorded. The results of ELISA revealed that 27 (33.7%) and 4 (5%) samples were positive for T. gondii IgG and IgM antibodies, respectively. The estimated incidence of toxoplasmosis increased significantly in the 21-30 years age group and females (P<0.05), compared to other groups. The wide prevalence of toxoplasmosis was observed in Iraq, especially in Najaf province, which was reflected in the results of the study after taking random samples from different places with no symptoms of the disease. Therefore, all members of the community should undergo periodic examinations to diagnose possible infection through the most accurate tests.

Detection of Toxoplasma gondii Infections using Virus-Like Particles Displaying T. gondii ROP4 Antigen

Toxoplasma gondii ME49 infections are typically diagnosed by serological tests. However, serological diagnosis of RH strain-induced toxoplasmosis remains unknown. In order to develop seradiagnosis of above 2 kinds of infections, we generated recombinant virus-like particles (VLPs) displaying the T. gondii rhoptry protein 4 (ROP4) and evaluated their potential in T. gondii ME49 or RH strain infection diagnostics. Mice were orally infected with either the tachyzoites of T. gondii (RH) or cysts of T. gondii (ME49) at various dosages, and sera were collected at regular intervals. ELISA-based serological tests were performed to assess IgG, IgM, and IgA antibody responses against ROP4 VLP antigen and tissue lysate antigen (TLA). Compared to TLA, IgG, IgM, and IgA levels to ROP4 VLP antigen were significantly higher in the sera of T. gondii RH-infected mice 1 and 2 week post-infection (PI). T. gondii-specific IgG antibody was detected at 1, 2, 4, and 8 week PI in the T. gondii ME49-infected mice with infection dose-dependent manner. These results indicated that the ROP4 VLP antigen was highly sensitive antigens detecting T. gondii RH and ME49 antibodies at an early stage.

Seroprevalence of Toxoplasma gondii, Rubella, Group A Streptococcus, CMV and HSV-1 in COVID-19 Patients with Vitamin D Deficiency

&lt;b&gt;Background and Objective:&lt;/b&gt; In recent years, respiratory tract viral infections have caused many pandemics that impact the whole world. To investigate the seropositivity of &lt;i&gt;Toxoplasma gondii&lt;/i&gt;, rubella, CMV, HSV-1 and group A &lt;i&gt;Streptococcus&lt;/i&gt; in recovered COVID-19 patients and correlate these findings with vitamin D levels. &lt;b&gt;Materials and Methods:&lt;/b&gt; A total of 417 COVID-19 patients with diarrhoea were enrolled in this study. Vitamin D and seroprevalence for &lt;i&gt;Toxoplasma gondii&lt;/i&gt;, rubella, CMV, HSV-1 and group A &lt;i&gt;Streptococcus&lt;/i&gt; were evaluated and correlated. &lt;b&gt;Results:&lt;/b&gt; It was found that recent infection in COVID-19 patients with HSV-1, rubella, &lt;i&gt;Toxoplasma&lt;/i&gt; and CMV, respectively. IgG was detected indicating the development of adaptive immunity with all microbes. &lt;b&gt;Conclusion:&lt;/b&gt; Current study detected a correlation between vitamin D levels and HSV-1 and no correlation between this infection and vitamin D deficiency with the other microbes.

Serum IgG Titers Against Toxoplasma gondii in Uninfected Infants Exposed In Utero to Toxoplasmosis

OBJECTIVES

To describe the mean time of decrease of T. gondii IgG titers in uninfected infants exposed in utero to toxoplasmosis.

METHODS

A retrospective cohort study was conducted between 2008-2017, among infants under 12 months and exposed in utero to toxoplasmosis. Serial monthly monitoring of serum IgG titers were done till undetectable levels.

RESULTS

240 infants with mean gestational age at diagnosis of 19.2 weeks were included in the study. The mean (range) time for IgG level to become undetectable was 7.9 (0.8-25.0) months. 14 infants became negative between 13-24 months.

CONCLUSIONS

Majority of asymptomatic infants exposed in utero to T. gondii become seronegative before 12 months of age.

ACUTE MYOCARDITIS WITH CARDIOGENIC SHOCK AND MULTIPLE ORGAN FAILURE, FOLLOWED BY BILATERAL PANUVEITIS MASQUERADING AS ENDOGENOUS ENDOPHTHALMITIS, DUE TO TOXOPLASMA GONDII IN AN IMMUNOCOMPETENT PATIENT

PURPOSE

To report a case of systemic and ocular toxoplasmosis in an immunocompetent patient, who developed myocarditis with resulting cardiogenic shock and multiple organ failure, followed by bilateral panuveitis masquerading as endogenous endophthalmitis.

METHODS

Single case report with images.

RESULTS

A 59-year-old man with a history of monoclonal gammopathy of undetermined significance and associated scleromyxedema but otherwise immunocompetent was admitted to the intensive care unit for cardiogenic shock and multiple organ failure due to presumed viral myocarditis. After hospital discharge, ophthalmic examination revealed what seemed to be endogenous fungal endophthalmitis in both eyes. The ocular inflammation failed to improve on local and systemic antifungal therapies. After repeated testing and vitrectomy, the causative organism responsible for his intraocular inflammation remained elusive. The patient was then found to have significantly elevated serum titers of anti-Toxoplasma gondii IgG and IgM, followed by an appearance of a focal retinochoroidal lesion more typical of ocular toxoplasmosis. Systemic anti-Toxoplasma therapy led to resolution of intraocular inflammation, and the patient had since fully recovered from the myocarditis and its multiple comorbidities. Of note, myocardial biopsy and polymerase chain reaction testing of aqueous and vitreous fluids were all negative for Toxoplasma.

CONCLUSION

Even in an immunocompetent patient, Toxoplasma can result in myocarditis with significant morbidities and even death, and its ocular manifestation may be quite different from the classic focal retinochoroiditis. In addition, polymerase chain reaction analysis of ocular fluids can be unreliable in an immunocompetent host, and thus treatment decision should be guided by clinical history and examination findings.

Association between lymphadenopathy after toxoplasmosis seroconversion in pregnancy and risk of congenital infection

The aim of the study was to describe the pregnancy outcome of a large cohort of women with toxoplasmosis seroconversion in pregnancy and to investigate the relation between maternal lymphadenopathy and risk of congenital toxoplasmosis (CT). This was a retrospective study involving women with confirmed toxoplasmosis seroconversion in pregnancy between 2001 and 2017. Women were clinically evaluated for lymphadenopathy and classified as follows: lymphadenopathy absent (L-) or lymphadenopathy present (L+). The mothers were treated and followed-up according to local protocol, and neonates were monitored at least for 1 year in order to diagnose CT. A total of 218 women (one twin pregnancy) were included in the analysis. Pregnancy outcome was as follows: 149 (68%) of children not infected, 62 (28.3%) infected, 4 (1.8%) first trimester termination of pregnancy, 2 (0.9%) first trimester miscarriages, and 3 (1.4%) stillbirths (of which one already counted in the infected cohort). 13.8% of women were L+ , and they were nearly three times more likely to have a child with CT compared to L- women (aOR, 2.90; 95%CI, 1.28-6.58). Moreover, the result was still statistically significant when the analysis was restricted to 81 children whose mothers were clinically examined and received treatment within 5 weeks from estimated time of infection. In conclusion, there is a positive association between L+ status in pregnant women, and risk of CT also confirmed when restricting the analysis to women with early diagnosis of seroconversion and treatment. This data could be very useful in counselling pregnant women with toxoplasmosis seroconversion and lead to direct a more specific therapeutic and diagnostic protocol.

Prevalence of Serum Specific Antibodies to TORCH Agents in a Cohort of Children Using DiaSorin "Flash" Chemiluminescence Technology

BACKGROUND

Our study was undertaken to detect the prevalence of serum specific antibodies to TORCH agents in children by establishing the presence of the specific IgM antibodies with DiaSorin "Flash" chemiluminescence technology.

MATERIALS AND METHODS

A total of 804 blood samples were collected for the detection of the Toxoplasma IgM; 2,048 cases were collected for CMV IgM, and 337 cases were collected for HSV-1/2 IgM, over a period of 9 months (from January 2019 to September 2019).

RESULTS

In our cohort, a total of 103 samples (12.8%) were found to be seropositive for Toxoplasma, 1,551 samples (75.7%) were positive for CMV and 174 samples (51.6%) were positive for the HSV-1/2 infections. The perinatal CMV infection was observed in 11.9% of the patients with positive serology for CMV.

CONCLUSIONS

The routine antenatal screening with chemiluminescence technology should be recommended in general population to avoid congenital malformations, as long as the prevalence of serum specific antibodies to TORCH agents is high and seropositivity rate increases with age.

Azathioprine-induced toxoplasma gondii infection in a patient with Crohn's disease with NUDT15 variation: A case report

INTRODUCTION

Azathioprine (AZA) has been widely used for the treatment of various immune-related diseases and has become a mainstay in the treatment of inflammatory bowel disease. However, patients with genetic mutations may experience severe adverse events when treated with azathioprine. Most of the previous literature focused on the TPMP gene-related adverse reactions, herein, we report a case of Crohn's disease patient with nucleoside diphosphate-linked moiety X motif 15 gene (NUDT15) variation and wild-type TPMP gene who developed toxoplasma gondii infection after azathioprine treatment.

PATIENT CONCERNS

A 56-year-old Crohn's disease patient developed toxoplasma gondii infection within 2 months after the administration of azathioprine; however, he had no relevant high-risk factors.

DIAGNOSIS

Subsequent genetic testing revealed that the patient was heterozygous for NUDT15. Therefore, it was reasonable to consider that the patient's genetic mutation resulted in reduced tolerance to azathioprine, leading to low immunity and eventually toxoplasma infection.

INTERVENTIONS

AZA was then discontinued; after anti-infection, antipyretic and other supportive treatments were administered, the patient's condition gradually improved.

OUTCOMES

The patient was followed up at 1, 3, and 6 months after discharge; fortunately, he was in good health.

CONCLUSION

We report a case of Crohn's disease in a patient who developed severe pneumonia caused by toxoplasma gondii infection due to the administration of AZA, with normal TPMP gene but NUDT15 gene mutation. This indicates that NUDT15 variation may contribute to severe adverse events in patients treated with azathioprine, and we suggest that NUDT15 genotype be detected before the use of azathioprine in order to provide personalized therapy and reduce side effects.

Temperature and Time Dependent Variations in Anti-Toxoplasma gondii Antibody Titrations in Serum Samples

OBJECTIVE

This study aimed to determine the temperature- and time-dependent variations in the anti-Toxoplasma gondii (T. gondii) antibody titres in serum samples collected from T. gondii-infected patients.

METHODS

During May 2017-February 2018, five serum samples (stored at different time periods and conditions) from pregnant or non-pregnant women aged ≥18 years who were infected with T. gondii and had applied to our Parasitology Department of Hafsa Sultan Hospital, Manisa Celal Bayar University, were investigated for the anti-T. gondii IgG antibody levels by enzyme linked fluorescent assay (ELFA).

RESULTS

The serum samples of five female volunteers who were infected with T. gondii that were stored at room temperature (20/25 °C), in a cargo package (+4/+8 °C), in a refrigerator (+4 °C), in a deep freezer (-16/-20 °C) and in an incubator (+37 °C) were tested at 0, 24, 48 and 72 hours after infection with the ELFA test. No statistically significant difference was observed in the anti-T. gondii IgG antibody titres (p>0.05).

CONCLUSION

The results obtained from the patients infected with T. gondii at different times and conditions of up to 72 hours were not significantly affected clinically. Hence, more comprehensive data can be obtained by increasing the number of patients and storing the serum samples for more than 72 hours.

What obstetricians should be aware of: serious side effects of antibiotic toxoplasmosis treatment in pregnancy

Infection with Toxoplasma gondii is usually an asymptomatic or oligosymptomatic, self-limiting disease in immunocompetent individuals. However, during the pregnancy, primary infection can lead to transplacental vertical transmission resulting in congenital toxoplasmosis with possible severe sequelae. The efficacy of systematic screening remains controversial and the effect of antibiotic treatment is unclear. Although main side effects of antibiotic drugs used for toxoplasmosis are well known, mostly from malaria treatment, there is a lack of information about occurrence in pregnant woman treated for toxoplasmosis. We report a case of a healthy pregnant woman with primary toxoplasmosis infection in the second trimester, who developed a severe adverse reaction in form of hypersensitivity pneumonia after antibiotic treatment with pyrimethamine and sulfadiazine and discuss the literature.

Detection of toxoplasmic encephalitis in HIV positive patients in urine with hydrogel nanoparticles

BACKGROUND

Diagnosis of toxoplasmic encephalitis (TE) is challenging under the best clinical circumstances. The poor clinical sensitivity of quantitative polymerase chain reaction (qPCR) for Toxoplasma in blood and CSF and the limited availability of molecular diagnostics and imaging technology leaves clinicians in resource-limited settings with few options other than empiric treatment.

METHOLOGY/PRINCIPLE FINDINGS

Here we describe proof of concept for a novel urine diagnostics for TE using Poly-N-Isopropylacrylamide nanoparticles dyed with Reactive Blue-221 to concentrate antigens, substantially increasing the limit of detection. After nanoparticle-concentration, a standard western blotting technique with a monoclonal antibody was used for antigen detection. Limit of detection was 7.8pg/ml and 31.3pg/ml of T. gondii antigens GRA1 and SAG1, respectively. To characterize this diagnostic approach, 164 hospitalized HIV-infected patients with neurological symptoms compatible with TE were tested for 1) T. gondii serology (121/147, positive samples/total samples tested), 2) qPCR in cerebrospinal fluid (11/41), 3) qPCR in blood (10/112), and 4) urinary GRA1 (30/164) and SAG1 (12/164). GRA1 appears to be superior to SAG1 for detection of TE antigens in urine. Fifty-one HIV-infected, T. gondii seropositive but asymptomatic persons all tested negative by nanoparticle western blot and blood qPCR, suggesting the test has good specificity for TE for both GRA1 and SAG1. In a subgroup of 44 patients, urine samples were assayed with mass spectrometry parallel-reaction-monitoring (PRM) for the presence of T. gondii antigens. PRM identified antigens in 8 samples, 6 of which were concordant with the urine diagnostic.

CONCLUSION/SIGNIFICANCES

Our results demonstrate nanoparticle technology's potential for a noninvasive diagnostic test for TE. Moving forward, GRA1 is a promising target for antigen based diagnostics for TE.