Systematic review on molecular detection of congenital and neonatal infections caused by TORCH and SARS-CoV-2 in newborns' cerebrospinal fluid.

OBJECTIVE: To verify the use and identify advantages of molecular methods for congenital infections diagnosis in cerebrospinal fluid of neonates. DATA SOURCE: The review was registered in the International Prospective Register of Systematic Reviews (PROSPERO), under CRD42021274210. The literature search was performed in databases: PubMed, Virtual Health Library/ Latin American and Caribbean Center on Health Sciences Information (VHL/BIREME), Scopus, Web of Science, Excerpta Medica database (EMBASE), Cochrane, ProQuest, and EBSCOhost. The search was carried out from August to October 2021 and updated in December 2022, respecting the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The selection sequence was: 1) Duplicate title removal; 2) Examination of titles and abstracts; 3) Full-text retrieval of potentially relevant reports; and 4) Evaluation of the full text according to eligibility criteria by two independent authors. Inclusion criteria considered randomized and non-randomized control trials, longitudinal, cross-sectional, and peer-reviewed studies in humans, published in English, Spanish, Italian, and Portuguese, with newborns up to 28 days old who had congenital neuroinfections by toxoplasmosis, rubella, cytomegalovirus, herpes simplex (TORCH), and others such as Treponema pallidum, Zika, parvovirus B-19, varicella zoster, Epstein-Barr, and SARS-CoV2, diagnosed by polymerase chain reaction (PCR). Two evaluators extracted the following information: author, year of publication, nationality, subjects, study type, methods, results, and conclusion. DATA SYNTHESIS: The most studied pathogen was herpes simplex. Several articles reported only nonspecific initial symptoms, motivating the collection of cerebrospinal fluid and performing PCR for etiological investigation. CONCLUSIONS: Molecular methods are effective to detect pathogen genomes in cerebrospinal fluid, which can impact clinical evolution and neurological prognosis.

Evaluation of different cut-off points for IgG avidity and IgM in the diagnosis of acute toxoplasmosis in pregnant women participating in a congenital toxoplasmosis screening program.

The main social impact of toxoplasmosis stems from its ability to be vertically transmitted. Postnatally acquired infection is generally asymptomatic in approximately 70-90% of cases, making diagnosis often dependent on laboratory tests using serological methods to search for anti-T. gondii antibodies. This study aimed to investigate the ability of the VIDAS TOXO IgG avidity and VIDAS TOXO IgM assays to confirm recent toxoplasmosis. In total, 341 pregnant women with suspected acute toxoplasmosis were systematically monitored in the Program for Control of Congenital Toxoplasmosis in Minas Gerais State, Brazil. We conducted an observational analytical-descriptive cross-sectional study and grouped according to clinical and laboratory criteria as having acute or chronic toxoplasmosis. The VIDAS TOXO IgG avidity and VIDAS TOXO IgM assays were evaluated to investigate the capacity to identify acute infection. IgG avidity showed good performance in identifying acute toxoplasmosis when the IgG avidity index was lower than or equal to 0.1. Values greater than or equal to 3.16 according to the TOXO IgM kit were associated with a greater chance of acute infection. These results may contribute to a more adequate diagnosis of acute gestational toxoplasmosis and, consequently, the avoidance of inadequate or unnecessary treatments.

Biological screening for congenital toxoplasmosis in newborns from Jataí, Goiás, Brazil: a cross-sectional study.

OBJECTIVE: To conduct a serological screening for toxoplasmosis in the heel prick test and to evaluate its epidemiological aspects in newborns and postpartum women in Jataí, Goiás. METHOD: Cross-sectional epidemiological study for the biological screening of newborns in Jataí, Goiás. RESULTS: The study participants amounted to 228 newborns, whose samples were collected between the third and seventh day of life. IgG antibodies against Toxoplasma gondii were detected in 40.79% (93/228) of the samples; out of these, 23.6% (22/93) had high IgG antibody titers, leading to the collection of two other peripheral blood samples and the detection of a decrease in these titers. CONCLUSION: The findings show the importance of strengthening actions in primary health care to prevent infection and training health professionals in this area to equip them with information regarding cases of reinfection and reactivation of infection in pregnant women, minimizing risks for babies.

Novel paradigm enables accurate monthly gestational screening to prevent congenital toxoplasmosis and more.

BACKGROUND: Congenital toxoplasmosis is a treatable, preventable disease, but untreated causes death, prematurity, loss of sight, cognition and motor function, and substantial costs worldwide. OBJECTIVES: We asked whether high performance of an Immunochromatographic-test (ICT) could enable accurate, rapid diagnosis/treatment, establishing new, improved care-paradigms at point-of-care and clinical laboratory. METHODS: Data were obtained in 12 studies/analyses addressing: 1-feasibility/efficacy; 2-false-positives; 3-acceptability; 4-pink/black-line/all studies; 5-time/cost; 6-Quick-Information/Limit-of-detection; 7, 8-acute;-chronic; 9-epidemiology; 10-ADBio; 11,12-Commentary/Cases/Chronology. FINDINGS: ICT was compared with gold-standard or predicate-tests. Overall, ICT performance for 1093 blood/4967 sera was 99.2%/97.5% sensitive and 99.0%/99.7% specific. However, in clinical trial, FDA-cleared-predicate tests initially caused practical, costly problems due to false-positive-IgM results. For 58 persons, 3/43 seronegative and 2/15 chronically infected persons had false positive IgM predicate tests. This caused substantial anxiety, concerns, and required costly, delayed confirmation in reference centers. Absence of false positive ICT results contributes to solutions: Lyon and Paris France and USA Reference laboratories frequently receive sera with erroneously positive local laboratory IgM results impeding patient care. Therefore, thirty-two such sera referred to Lyon's Reference laboratory were ICT-tested. We collated these with other earlier/ongoing results: 132 of 137 USA or French persons had false-positive local laboratory IgM results identified correctly as negative by ICT. Five false positive ICT results in Tunisia and Marseille, France, emphasize need to confirm positive ICT results with Sabin-Feldman-Dye-test or western blot. Separate studies demonstrated high performance in detecting acute infections, meeting FDA, CLIA, WHO REASSURED, CEMark criteria and patient and physician satisfaction with monthly-gestational-ICT-screening. CONCLUSIONS/SIGNIFICANCE: This novel paradigm using ICT identifies likely false positives or raises suspicion that a result is truly positive, rapidly needing prompt follow up and treatment. Thus, ICT enables well-accepted gestational screening programs that facilitate rapid treatment saving lives, sight, cognition and motor function. This reduces anxiety, delays, work, and cost at point-of-care and clinical laboratories. TRIAL REGISTRATION: NCT04474132, https://clinicaltrials.gov/study/NCT04474132 ClinicalTrials.gov.

Employing digital PCR for enhanced detection of perinatal Toxoplasma gondii infection: A cross-sectional surveillance and maternal-infant outcomes study in El Salvador.

Toxoplasma gondii is a parasitic infection that can be transmitted in utero, resulting in fetal chorioretinitis and other long-term neurological outcomes. If diagnosed early, pregnancy-safe chemotherapeutics can prevent vertical transmission. Unfortunately, diagnosis of acute, primary infection among pregnant women remains neglected, particularly in low-and-middle-income countries. Clinically actionable diagnosis is complex due to the commonality of infection during childhood and early adulthood which spawn long-last antibody titers and historically unreliable direct molecular diagnostics. The current study employed a cross-sectional T. gondii perinatal surveillance study using digital PCR, a next generation molecular diagnostic platform, and a maternal-fetal outcomes survey to ascertain the risk of vertical toxoplasmosis transmission in the Western Region of El Salvador. Of 198 enrolled mothers at the time of childbirth, 6.6% had evidence of recent T. gondii infection-85% of these cases were identified using digital PCR. Neonates born to these acutely infected mothers were significantly more likely to meconium aspiration syndrome and mothers were more likely to experience labor and delivery complications. Multivariable logistic regression found higher maternal T. gondii infection odds were associated with the presence of pet cats, the definitive T. gondii host. In closing, this study provides evidence of maternal T. gondii infection, vertical transmission and deleterious fetal outcomes in a vulnerable population near the El Salvador-Guatemala border. Further, this is the first published study to show clinical utility potential of digital PCR for accurate diagnosis of congenital toxoplasmosis cases.

In defense of children's brain: reshuffling the laboratory toolbox for the diagnosis of congenital toxoplasmosis.

For decades, an immunosorbent agglutination assay (ISAGA) has been considered the gold standard method for the detection of Toxoplasma gondii-specific IgM in infants for the diagnosis of congenital toxoplasmosis (CT). The Toxoplasma IgM ISAGA was consistently reported as having superior sensitivity. Unfortunately, the commercial kit for the detection of Toxoplasma IgM ISAGA will no longer be available in 2024 and alternatives will only be available at a handful of reference laboratories as in-house or laboratory-developed tests. In a recent study, S. Arkhis, C. Rouges, N. Dahane, H. Guegan, et al. (J Clin Microbiol 62:e01222-23, 2024, https://doi.org/10.1128/jcm.01222-23), reported that the performance of the PLATELIA Toxo IgM was comparable to that of the ISAGA method for the diagnosis of CT. A second study revealing similar results supports the PLATELIA Toxo IgM as the new gold standard for the detection of T. gondii-specific IgM in infants. Although the laboratory toolbox for CT diagnosis has been reshuffled successfully, it is by universally implementing all available serological and molecular tools at the earliest possible time during gestation that we can best defend children's brain from the potential harm caused by trans-placentally transmitted T. gondii.

Congenital Toxoplasmosis and Long-term Outcomes

Objective: Congenital toxoplasmosis (CT) can have severe early and late sequelae in children. In this study, we aimed to evaluate the demographic, clinical, treatment characteristics of patients diagnosed with congenital Toxoplasma infection and to highlight the long-term complications of the patients. Methods: Patients with CT were included in this study who were followed between 2010 and 2022 in Cukurova University Medical Faculty Hospital. Demographic, clinical and treatment characteristics were searched retrospectively. In the diagnosis of maternal and CT, Toxoplasma IgM, IgG, IgG avidity, T. gondii polymerase chain reaction tests were used along with clinical and symptoms. Results: Eighteen children (two twins) with CT and their mothers (n=16) were included in the study. Median age was 1 month. Ten (55.5%) of the children were male. CT diagnosis was made during pregnancy in 7 mothers (resulting in 8 babies) and postnatally in 9 mothers (resulting in 10 babies). The mothers of 5 (31.1%) babies with CT received spiramycin treatment during pregnancy. Three (60%) of 5 pregnant women who received spiramycin were diagnosed in the first trimester, 4 (80%) of the babies did not have any sequale and only 1 (20%) had microphthalmia. Ocular involvement was the most common presentation of the disease occured in 10 patients (55.5%), hydrocephalus and intracranial calcification developed in five patients (27.7%). Hearing loss developed in 2 (11.1%) patients. During the follow-up period, seizures developed in 3 patients (16.6%), microcephaly in 2 patients (11.1%), and neurodevolopmental retardation in 7 patients (38.8%), two of the patients had severe mental retardation. One (5.5%) patient with hydrocephalus died at 36 months of age due to complications after ventriculoperitoneal shunt application. Conclusion: In our study, we observed severe sequelae in vision, hearing, and neurodevelopmental aspects in children diagnosed with CT at birth and during follow-ups. Early diagnosis and treatment of infants, along with the detection of Toxoplasma infection during pregnancy, are essential in preventing severe sequelae that may arise due to CT.

Long-term Ocular Outcomes in Congenital Toxoplasmosis Treated Perinatally.

BACKGROUND: Congenital toxoplasmosis (CT) can be accompanied by serious organ manifestations, particularly retinochoroiditis, and may occur throughout life. We aimed to monitor long-term ocular prognosis in a large French cohort of patients with CT and its changes over time in the context of mandatory prenatal screening (since 1992) and incidence decrease since 2008. METHODS: Patients with CT diagnosed between 1987 and 2021 were prospectively included and followed for up to 35 years. The effect of the period of conception on the risk of first retinochoroiditis has been tested using a flexible extension of the Cox model. Incidence rates of retinochoroiditis were estimated. RESULTS: A total of 646 infected live born children were followed for a median of 12 years (range, 0.5-35); 187 patients (29%) had at least 1 ocular lesion (first at a median age of 5 years; range, 0-26 years) with peaks at 7 and 12 years. Early maternal infection and the presence of nonocular signs at birth were associated with a higher risk of retinochoroiditis, whereas delayed diagnosis of CT (after birth versus before or at birth) was associated with a lower risk (13% decrease for each additional month after birth; P = .01). A period effect for the risk of developing retinochoroiditis in patients born after 2008 was not detected. CONCLUSIONS: Despite prenatal screening and prolonged perinatal treatment, retinochoroiditis is not a rare event in French patients with CT and can occur well into adulthood, with peak incidences at 7 and 12 years of age. It rarely causes severe damage but warrants regular follow-up into adulthood.

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.

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®.

Title: Performances comparatives des tests ISAGA IgM et ELISA pour le diagnostic des infections maternelles et congénitales à Toxoplasma : quelle technique pourrait remplacer ISAGA IgM ? Abstract: Le test d'immunocapture ISAGA pour la détection des immunoglobulines M anti-Toxoplasma est une technique manuelle connue pour son excellente sensibilité et spécificité. Le but de cette étude rétrospective et multicentrique était de comparer les performances et la concordance entre l'ISAGA et d'autres techniques de détection d'IgM avant l'arrêt de la commercialisation de l'ISAGA. Les performances analytiques des différents tests ont été évaluées à partir de 1 341 échantillons de sérum d'adultes présentant des IgM positives et des IgG négatives à Toxoplasma gondii, et de 1 206 sérums de nouveau-nés nés de mères présentant une séroconversion. La concordance entre les tests a été évaluée sur 13 506 échantillons de sérum d'adultes et 5 795 sérums d'enfants. La sensibilité de Toxo-ISAGA IgM® (adultes 98,7 %, nouveau-nés 63,1 %) était similaire à celle de Platelia Toxo IgM® (adultes 94,4 %, nouveau-nés 64,6 %) et significativement supérieure à celle de Liaison Toxo IgM® (adultes 90,6 %), Architect/Alinity Toxo IgM® (adultes 95,7 %, nouveau-nés 48,6 %) et Vidas Toxo IgM® (adultes 81,8 %, nouveau-nés 17,5 %). Cependant, les spécificités variaient entre 24,4 % (Platelia Toxo IgM®) et 95,2 % (Liaison Toxo IgM®) chez les adultes et étaient >95 % pour tous les tests chez les nouveau-nés. L'analyse des coefficients kappa a montré une meilleure concordance entre ISAGA IgM® et les autres tests chez les enfants (0,75­0,83%) que chez les adultes (0,11­0,53%). Nous concluons qu'en l'absence de Toxo-ISAGA IgM®, l'association d'une technique très sensible (Platelia Toxo IgM® ou Architect/Alinity Toxo IgM®) et d'une technique très spécifique (Vidas Toxo IgM® ou Liaison Toxo IgM®) est recommandée pour la détection des IgM dans les sérums adultes. Pour les nouveau-nés, Platelia Toxo IgM® apparaît comme la meilleure alternative en remplacement de Toxo-ISAGA IgM®.

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.

Toxoplasma gondii infections in pediatric neurosurgery.

Toxoplasma gondii is a parasite that is estimated to infect one-third of the world's population. It is acquired by ingesting contaminated water and food specially undercooked meat, contact with domestic or wild feline feces, and during pregnancy by transplacental transmission.Immunocompetent hosts are usually asymptomatic, and infection will be self-limited, while those patients whose immune system is debilitated by HIV infection, immunosuppressive therapy, long-term steroid treatment, and fetuses infected during gestation will show evidence of systemic activity which is more severe in the central nervous system and eyes due to insufficient immune response caused by their respective blood barriers. Congenital toxoplasmosis has an estimated incidence of 8% in mothers who were seronegative at the beginning of their pregnancy. Infection in the first trimester may result in spontaneous abortion or stillbirth; however, it is estimated that the highest risk for vertical transmission is during the second and third trimesters when blood flow and placenta thickness favor parasitic transmission.Congenital toxoplasmosis can be detected with periodic surveillance in endemic areas, and with appropriate treatment, the risk of vertical transmission can be reduced, and the severity of the disease can be reversed in infected fetuses.While most infected newborns will show no evidence of the disease, those who suffer active intrauterine complications will present with cerebral calcifications in 8-12% of cases, hydrocephalus in 4-30%, and chorioretinitis in 12-15%. Also, seizure disorders, spasticity, and varying degrees of neurocognitive deficits can be found in 12%.Four distinct patterns of hydrocephalus have been described: aqueductal stenosis with lateral and third ventricle dilatation, periforaminal calcifications leading to foramen of Monro stenosis with associated asymmetrical ventricle dilatation, a mix of aqueductal and foramen of Monro stenosis, and overt hydrocephalus without clear evidence of obstruction with predominant dilatation of occipital horns (colpocephaly).While all patients diagnosed with congenital toxoplasmosis should undergo pharmacological treatment, those presenting with hydrocephalus have traditionally been managed with CSF shunting; however, there are reports of at least 50% success when selected cases are treated with endoscopic third ventriculostomy. Successful hydrocephalus management with appropriate treatment leads to better intellectual outcomes.

Contribution of serology in congenital toxoplasmosis diagnosis: results from a 10-year French retrospective study.

This study aimed to evaluate different serological strategies for the postnatal diagnosis of congenital toxoplasmosis (CT) and establish a biological algorithm for CT diagnosis. The study analyzed serological data of immunoglobulins M, A, and G (IgM, IgA, IgG) performed by immunoenzymatic and compared immunological profile (CIP) assays in 668 newborns with CT diagnosis across four testing periods: P1 (D0- D10), P2 (D11-D35), P3 (D36-D45), and P4 (>D45). Forty-nine percent of the 668 CT cases were diagnosed during P1 and 34%, 4%, and 12% during P2, P3, and P4, respectively. CIP assays detected neosynthetized IgMs/IgGs in 98% of CT cases diagnosed during P1, while IgMs and IgAs were detected in 90% and 57% of CT cases diagnosed during P2 and in 88% and 67% of diagnoses made during P3, respectively. Detection of neosynthesized IgMs/IgGs, IgMs, and IgAs by immunoassay contributed to CT diagnosis in 81%, 77%, and 60% of cases, respectively. In total, 46% of serum samples were positive for all three parameters, 27% for two, and 27% for one of the three. The study recommends using the CIP assay as standard during P1 for CT diagnosis and IgM and IgA immunoassays after P1. A clinical and biological follow-up in a specialized center with a close collaboration between biologists and clinicians is highly recommended to increase the chances of early diagnosis. Overall, this study provides useful information for the development of a biological algorithm for CT diagnosis, which can aid in early detection and appropriate treatment of this disease.

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.

Unspecific congenital toxoplasmosis in a two-month-old baby.

A two-month-old baby boy diagnosed with unspecific congenital toxoplasmosis was referred by a pediatrician to the Clinical Parasitology referral center at the Faculty of Medicine, Universitas Indonesia. Baby was post-hospitalized in the NICU and required ventilation support for one month. Furthermore, there was history of from various medical conditions, such as intracranial bleeding, convulsion, hypertrophic cardiomyopathy, retinopathy, and renal failure. After two month, there was no significant weight gain, anti-Toxoplasma IgM showed positive results, and anti-Toxoplasma IgM and IgG of the mother were also positive. Baby and mother were successfully treated with pyrimethamine, cotrimoxazole, and folinic acid for one month. At 2 years, there signs of normal motoric, eye, and hearing development with underdeveloped kidneys. Therefore, pre-pregnancy counseling and education aimed at preventing toxoplasmosis during pregnancy should be increased and conducted routinely by health workers or trained cadres to reduce the risk of fetal defects.

Congenital Toxoplasmosis Diagnosis: Current Approaches and New Insights.

PURPOSE: The aim of this study is to describe and discuss current disadvantages in congenital toxoplasmosis (CT) diagnosis, and what can be improved or changed through new perspectives and technological advances. METHODS: We used Pubmed, Cochrane, and EBSCO databases to research publications from 10 years to date describing current diagnostic methods for CT. The keywords used for this Mini-Review were Toxoplasma gondii, congenital toxoplasmosis, diagnosis, and prospects using Boolean operators such as AND, OR, identifying scientific publications highlighting the importance of implementing new diagnostic methods. RESULTS: Current diagnosis methods have several disadvantages, i.e., time-consuming, low sensitivity or specificity, and non-cost effective, that bring up the necessity of improving or developing new approaches. Recombinant proteins can help improve specificity by generating tests that use circulating strains in a specific geographical region, SAG1 and BAG1, as they are expressed during a particular stage of the disease (acute or chronic, respectively), for its use in serological diagnoses, such as capture ELISA and immunochromatography. Point of Care (POC) tests are methods performed at the patient care site, which leads to rapid patient treatment; despite the advantages, several improvements and perspectives are necessary to be implemented globally. CONCLUSIONS: Although already established diagnosis methods for CT may be sufficient in some regions, there is still a persistent demand to develop tests with higher throughput, cost, and time reduction in developing countries, where prevalence is high. New approaches in CT diagnosis, such as recombinant proteins, capture ELISA, immunochromatography, and POC tests methods, can increase performance in terms of specificity and sensitivity simplifying diagnostic tests' requirements.

IgM triplet in neonatal diagnosis by immunoblotting and its potential use as a diagnostic marker for congenital toxoplasmosis.

Primary infection during pregnancy by the protozoan Toxoplasma gondii can be worrisome because transmission to the fetus may lead to congenital toxoplasmosis (CT). Neonatal diagnosis is usually performed by serological profile comparison of the mother and newborn. As previously reported in 2012 by C. L'Ollivier et al., three IgM bands at 75, 90 and 100 kDa called the "IgM triplet" has caught our attention and seems to be pathognomonic of CT. This retrospective multicenter study involved nine reference laboratories included in the French National Reference Center for Toxoplasmosis network and concerned determining the specificity and sensitivity of this IgM triplet. On this basis, we were able to propose a new read of the comparison of IgG and IgM immunoblot profiles of mother and infant to increase the sensitivity of this diagnostic marker. The effect of the trimester of pregnancy at the time of infection, but also of maternal treatment with pyrimethamine/sulfadiazine/folinic acid on the presence of this IgM triplet in the infant, could be studied. The presence of the triplet appears pathognomonic for the diagnosis of CT, and it increased the sensitivity of the immunoblot assay from 55.04% to 72.48%. As a result, it would be wise to enhance conventional immunoblot reading by adding the presence of the three IgM bands in the infant pattern for neonatal diagnosis of CT.

Title: La triplette IgM dans le diagnostic néonatal par immunoblot et son utilisation potentielle comme marqueur diagnostique de la toxoplasmose congénitale. Abstract: La primo-infection pendant la grossesse par le protozoaire Toxoplasma gondii peut se révéler préoccupante car la transmission au fœtus peut conduire à une toxoplasmose congénitale (TC). Un diagnostic néonatal est généralement réalisé par comparaison des profils sérologiques de la mère et du nouveau-né. Comme précédemment rapporté en 2012 par C. L'Ollivier et al., l'association de trois bandes d'IgM à 75, 90, et 100 kDa appelée la « triplette IgM ¼ a retenu notre attention et semble être pathognomonique de la TC. Cette étude rétrospective multicentrique impliquant neuf laboratoires de référence inclus dans le réseau du Centre National de Référence pour la Toxoplasmose a permis de déterminer la spécificité et la sensibilité de cette triplette IgM. Ainsi, cela a permis de proposer une nouvelle lecture de la comparaison des profils d'immunoblot IgG et IgM de la mère et du nourrisson pour augmenter la sensibilité de ce marqueur diagnostique. L'effet du trimestre de la grossesse au moment de l'infection mais aussi du traitement maternel par pyriméthamine/sulfadiazine/acide folinique sur la présence de la triplette IgM chez l'enfant a pu être analysé. La présence de cette triplette semble pathognomonique pour le diagnostic de TC et elle permet d'augmenter la sensibilité du test immunoblot de 55,04 % à 72,48 %. Ainsi, il pourrait être judicieux d'améliorer la lecture conventionnelle de l'immunoblot en ajoutant la présence des trois bandes IgM dans le schéma du nourrisson pour le diagnostic néonatal de TC.

Maternal anti-Toxoplasma gondii antibodies IgG2, IgG3 and IgG1 are markers of vertical transmission and clinical evolution of toxoplasmosis in the offspring.

Toxoplasma gondii can be transmitted vertically during pregnancy and may cause neurological, ocular, and even systemic damage to the offspring. Congenital toxoplasmosis (CT) can be diagnosed during gestation and/or after birth in the postnatal period. The timely diagnosis is highly relevant for efficient clinical management. The most common laboratory methods for diagnosing CT are based on Toxoplasma-specific humoral immune responses. However, these methods are of low sensitivity or specificity. In a previous study with a small number of cases, the comparison of anti-T. gondii IgG subclasses between mothers and their offspring showed promising results for CT diagnosis and prognosis. Thus, in this work, we analyzed specific IgG subclasses and IgA in 40 T. gondii-infected mothers and their children, of which 27 were congenitally infected and 13 uninfected. A higher frequency of anti-Toxoplasma IgG2, IgG3, IgG4, and IgA antibodies was observed in mothers and congenitally infected offspring. Of these, IgG2 or IgG3 were statistically the most conspicuous. In the CT group, maternal IgG3 antibodies were significantly associated with severe disease of the infants and IgG1 and IgG3 with disseminated disease. The results support that maternal anti-T. gondii IgG3, IgG2 and IgG1 are markers of congenital transmission and severity/spread of disease in the offspring.

First description of congenital toxoplasmosis after maternal coinfection with Toxoplasma gondii and severe acute respiratory syndrome coronavirus 2: a case report.

BACKGROUND: Congenital toxoplasmosis can be associated with serious clinical consequences from fetus to adulthood. Hence, early detection is required to minimize severe sequelae through appropriate therapy. We describe the first case of a congenital toxoplasmosis after maternal coinfection with Toxoplasma gondii and severe acute respiratory syndrome coronavirus 2 and the challenging serological diagnosis of the disease in this context. CASE PRESENTATION: A Caucasian boy was born at 27 weeks 2 days of gestation by cesarean section due to maternal COVID-19-related respiratory failure. Postpartum serological screening of the mother revealed a previously unrecognized active Toxoplasma gondii infection. The premature child initially tested negative for anti- Toxoplasma gondii immunoglobulin A and M antibodies 1, 2 and 4 weeks after birth, whereas immunoglobulin G antibodies were only weakly positive with no evidence of child-specific production. Neither neurological nor ophthalmological abnormalities were detected. Approximately 3 months after birth, serological testing indicated a congenital toxoplasmosis by presence of immunoglobulin A and M, in combination with a child-specific immunoglobulin G synthesis. Additionally, cerebrospinal fluid was tested positive for Toxoplasma gondii DNA. Although no clinical manifestations of congenital toxoplasmosis were detected, an antiparasitic therapy was initiated to minimize the risk of late sequelae. There were no hints for a transplacental transmission of severe acute respiratory syndrome coronavirus 2. CONCLUSION: This case raises the awareness of possible coinfections with the risk of transplacental transmission in cases of maternal coronavirus disease 2019. The report emphasizes the need for screening vulnerable patients for toxoplasmosis in general and especially in the context of pregnancy. It becomes evident that prematurity can complicate the serological diagnosis of congenital toxoplasmosis due to a delayed antibody response. Repeated testing is recommended to carefully monitor children at risk and especially those with a history of preterm birth.