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.

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.

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.

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®.

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.

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.

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.

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.

Discordant Congenital Toxoplasmosis and Cytomegalovirus Infection in Dichorionic Diamniotic Twins

BACKGROUND

Toxoplasmosis and cytomegalovirus (CMV) congenital infection present with similar clinical pictures. Both infections have long-term sequelae that can be mitigated by early detection and treatment. Coinfection is uncommonly reported.

METHODS

Dichorionic diamniotic twins born at 35 weeks of gestation were investigated for congenital infections due to abnormalities on the antenatal scan at 31 weeks of gestation. Antenatal investigations were delayed due to late booking and delay in maternal investigations. In the neonatal period, they suffered discordant symptoms and were both investigated for Toxoplasma gondii infection. This diagnosis was confirmed in twin 2 but proved difficult in twin 1 who had a weakly positive polymerase chain reaction with inconclusive serology. Twin 1 was also diagnosed with congenital CMV, further complicating the clinical picture. Toxoplasmosis can cause long-term sequelae, and definitive diagnosis requires serology at 12 months of age; in view of this, treatment for congenital toxoplasmosis was initiated in both twins. Twin 1 was also treated for congenital CMV.

RESULTS

Due to limitations in serological investigations in neonates, diagnosing congenital toxoplasmosis can be challenging, and initiating treatment may be warranted in suspected cases, given the risk of infective complications. Discordant presentations between twins are known in congenital toxoplasmosis and CMV, but coinfection has rarely been reported without concurrent immunocompromise. A high index of suspicion should be maintained in the twin of an infected neonate, and the possibility of multiple infections should be considered. Multidisciplinary working is crucial in reaching a diagnosis and treating appropriately.

Efficiency of a Single well IgG, IgM and IgA Anti T. gondii Fluorimetric Assay for Pre-natal Screening for Congenital Toxoplasmosis

Toxoplasmosis, worldwide protozoan disease, is usually benign, except when acute disease occurs in pregnant women, resulting in fetal infection with deaths or high morbidity after birth. Treatment blocks fetal infection or damage after infection, imposing a quick and effective diagnosis. Maternal infection is mostly asymptomatic thus regular serology are the main tool for detect seroconversion and acute infection in prenatal care. Screening test for specific anti T. gondii IgG, IgM and IgA must be quick, cheaper and available for the prenatal care. Fluorescent solid phase assays appears as a good alternative as they allow one well detection of IgG and IgM aside to allow high throughput in 384 wells. Here, we standardize and analyze a single well anti-T. gondii IgG, IgM and IgA immunosorbent fluorescent assay in a large sample of a public hospital. We construct conjugates for each immunoglobulin with specific fluorophores, which allows concomitant detection in a microplate fluorimeter, with stability and reproducibility, allowing cheaper 384 wells use. Tested in our 600 mother samples from a large public hospital, they presented the same reactivity as standard routine tests, but with adequate IgM and IgA screening, as adequately standardized in house ELISA, while the design of most commercial assays give false positive results. The few TFISA positive IgG, IgM and IgA samples also had low avidity IgG, confirming recent infection. TFISA will help a screening toxoplasmosis in pregnancy program in large cities, with , allowing testing large numbers of samples at low cost and must be considered for other serological purposes.

Hygiene measures as primary prevention of toxoplasmosis during pregnancy: A systematic review

Background Hygiene measures are recommended to prevent toxoplasmosis during pregnancy, although screening for seroconversion in pregnant women currently are debated and practices vary among countries. Objectives The purpose of this systematic literature review was to assess the effectiveness of hygiene measures during pregnancy to prevent toxoplasmosis infection. Search Strategy We followed the standard MOOSE and PRISMA criteria when conducting this systematic review and reporting the results. Selection criteria A systematic literature search was conducted for studies focused on congenital toxoplasmosis prevention, toxoplasmosis prevention during pregnancy, toxoplasmosis prevention and hygiene measures, which were published between 1970 and August 2020, using the databases of PubMed, Scope Med, EMBASE, and the Cochrane library. Data collection and analysis Our literature search identified 3964 articles, 3757 were excluded after review of title or abstract and 67 studies were considered relevant to the subject. We reviewed risk factors for toxoplasmosis infection during pregnancy and for congenital toxoplasmosis, preventive measures for toxoplasmosis during pregnancy, including: dietary recommendations, pet care measures, environmental measures, knowledge of risk factors and ways to control toxoplasmosis infection, knowledge of risk factors for infection by health professionals, knowledge of primary prevention measures by pregnant women. Conclusion: Hygiene measures are effective and applicable primary prevention to reduce toxoplasmosis and avoid congenital toxoplasmosis and its consequences. Funding No.

One severe case of congenital toxoplasmosis in China with good response to azithromycin

BACKGROUND

Most infants infected with Toxoplasma gondii are completely asymptomatic at birth, yet they may develop ocular and neurological sequelae in the first few months of life. Cases of congenital toxoplasmosis with severe jaundice early after birth combined with pancytopenia and splenomegaly are extremely rare. Here, we report on a rare case of congenital toxoplasmosis presenting with severe jaundice and hemolysis early after birth combined with pancytopenia and splenomegaly.

CASE PRESENTATION

A male preterm infant with severe jaundice and splenomegaly was admitted to our department. Laboratory examinations revealed severe hyperbilirubinemia, increased reticulocytes, and pancytopenia. After comprehensive analysis and examination, the final diagnosis was congenital toxoplasmosis, and the infant was treated with azithromycin and subsequently trimethoprim-sulfamethoxazole. Regular follow-up revealed congenital toxoplasmosis in both eyes, which was surgically treated, while neurofunctional assessment results were unremarkable. In this case of congenital toxoplasmosis combined with severe jaundice, we treated the infant with two courses of azithromycin, followed by trimethoprim-sulfamethoxazole after the jaundice resolved. Clinical follow-up indicated that this treatment was effective with few side effects; thus, this report may serve as a valuable clinical reference.

CONCLUSIONS

Timely diagnosis and adequate treatment are closely associated with congenital toxoplasmosis-related prognosis. Infants with congenital toxoplasmosis require long-term follow-up, focusing on nervous system development and ophthalmology.

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.

CONGENITAL TOXOPLASMOSIS ASSOCIATED WITH TRACTIONAL RETINAL DETACHMENT

PURPOSE

We report a case of congenital toxoplasmosis associated with retinal detachment.

METHODS

A 9-month-old white boy presented a unilateral tractional retina detachment associated with congenital toxoplasmosis retinochoroiditis.

RESULTS

The diagnosis is supported by positive IgG (>400) for toxoplasmosis and intracranial calcification on magnetic resonance imaging, along with positive family history of Toxoplasma infection in the mother.

CONCLUSION

Tractional retinal detachment is an infrequent and unconventional presentation of congenital Toxoplasma infection. Inflammatory interference with normal sequence of vitreous development may explain pathogenesis of tractional retinal detachments in the setting of congenital ocular toxoplasmosis.

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.

Impact of pre-analytic step duration on molecular diagnosis of toxoplasmosis for five types of biological samples

Introduction

Toxoplasma-PCR is essential to diagnose ocular, cerebral, disseminated and congenital toxoplasmosis. This multicenter study evaluated the impact of sample storage duration at +4°C on PCR assay performances in order to propose guidelines for the storage of samples during shipment or/and before PCR.

Materials and methods

Five matrices, amniotic (AF), cerebrospinal (CSF), and bronchoalveolar lavage fluids (BALF), whole blood (WB) and buffy coat (BC), were artificially spiked with different amounts of Toxoplasma gondii (20, 100, 500 tachyzoites per mL of sample) or with previously infected THP1 cells. DNA extractions were performed at day 0 and after 2, 4 and 7 days of storage at +4°C. Each extract was amplified at least twice by real-time PCR.

Results

A total of 252 spiked samples was studied. No increase of crossing point was observed and all samples were positive for AF, BALF, BC and infected THP1-spiked WB after up to 7 days at 4°C. For CSF spiked with 20 parasites/mL, only 50% of PCR reactions were positive at D7 (p<0.05). For WB spiked with type II parasites, all reactions remained positive at D7 but amplifications were significantly delayed from D2; and for WB spiked with RH strain, the proportion of positive reactions decreased at D7.

Conclusion

The storage of clinical samples at +4°C is compatible with the molecular detection of T. gondii parasites. Provided that PCR assays are performed in duplicate, storage of samples is possible up to 7 days. However, from the fifth day onwards, and for samples susceptible to contain low parasitic loads, we recommend to perform the PCR in multiplicate.

[Argentine consensus of congenital toxoplasmosis]

Mother-to-child transmission in Toxoplasma gondii infection occurs only when the infection is acquired for the first time during pregnancy. Diagnosis of maternal infection and the newborn is achieved by a combination of serological tests, clinical features and ultrasound images. An early diagnosis of maternal infection allows treatment that offers a reduction both in transmission rate and risk of congenital damage. The aim of this expert consensus was to review the scientific literature which would enable an update of the clinical practice guideline of prevention, diagnosis and treatment of congenital toxoplasmosis in our country.

Ocular Outcome of Brazilian Patients With Congenital Toxoplasmosis

BACKGROUND

Retinochoroiditis is the most frequent manifestation of congenital toxoplasmosis. We aimed to describe the ocular outcome and factors that may influence the visual prognosis of these patients.

METHODS

Cohort of patients with confirmed congenital toxoplasmosis seen between 1996 and 2017 in Porto Alegre, southern Brazil.

RESULTS

Seventy-seven patients were included, of which 65 (85.5%) were identified by routine screening. Median age at the end of the follow-up was 10 years (minimum 2, maximum 25). Retinochoroiditis was present in 55 patients (71.4%). New retinochoroidal lesions developed after the first year of life in 77.8% of the patients who began treatment after the fourth month of life, compared with 35.2% among those treated before 4 months of life (relative risk = 0.45, 95% confidence intervals: 0.27-0.75, P = 0.02) and 33.3% among those treated before 2 months of life (relative risk = 0.42, 95% confidence intervals: 0.25-0.72, P = 0.01). There was a peak incidence of new retinochoroidal lesions between 4 and 5 years and another peak between 9 and 14 years, the latter only among girls. Thirty-four patients with retinochoroiditis were followed up for 10 years or more, and the school performance was appropriate in 28 (82.4%).

CONCLUSIONS

The high incidence of new retinochoroidal lesions during the follow-up period indicates the importance of long-term follow-up of patients with congenital toxoplasmosis. Initiating treatment within the first 4 months of life, especially within the first 2 months, was a protective factor against the later development of retinochoroiditis. Despite the usual favorable prognosis, the high morbidity of congenital toxoplasmosis in Brazil was confirmed.

Toxoplasma gondii infection during pregnancy: a ten-year observation in the province of Trento, Italy

The study analysed the trend of toxoplasmosis infection in pregnancy by using antenatal serological screening and the incidence of the congenital condition in newborns in the province of Trento, Italy. Data from pregnant women who gave birth at local maternity units between 2009 and 2018 were obtained. The serological test results were collected from birth attendance certificates (BACs), the main - and mandatory - source of information used to monitor pregnancies, births and neonatal health in Italy. The BAC used in the province of Trento acquires the results of serological tests for a vast range of infections in pregnancy. The data collected from the BACs were integrated with those provided by the Hospital Information System (HIS), which was also used to collect data on the trimester in which the seroconversion occurred. A total of 45,492 pregnant women were analysed, of whom 24% were foreigners. The average coverage of serological screening in pregnancy was 99.7%. Mean overall prevalence of Toxoplasma gondii infection was 21.7% (95% CI: 21.3-22.1): in Italians the prevalence was 17.9% (95% CI: 17.5-18.30) and in foreign nationals 32.7% (95% CI: 32.26-33.13). The mean annual seroconversion rate was 0.35% (95% CI: 3.0-4.2) of susceptible women and 0.27% (95% CI: 2.2-3.4) of all pregnant women who were screened. The seroconversion rate was higher amongst foreign women (0.32%, 95% CI: 3.0-3.6) than Italian women (0.24%, 95% CI: 2.1-2.8). In all, 91.0% of seroconverted women were treated during pregnancy in accordance with the anti-toxoplasma protocol. Five cases of congenital infection were identified (2 amongst Italians and 3 amongst foreign women), amounting to an overall transmission rate of 4.0% (2.3% in Italians and 8.8% in foreigners). Transmission risk ranged from 0.0% in the first trimester to 19% in the third. The incidence of congenital toxoplasmosis, over the entire study period, was 0.012% live births (0.011% in Italians and 0.016% in foreigners). Data collection on infections in pregnancy through BAC allows area-based assessment. Although the quality of the data recorded in the BAC can be considered satisfactory, it was also necessary to access other information sources. The screening coverage was very high. The prevalence of toxoplasmosis infection was found to be higher in foreign mothers than in Italians, as well as seroconversion. The extent of serological screening and the high treatment rate helped to keep the risk of infection transmission to the foetus low and to achieve a very low rate of congenital infection.

A case of congenital toxoplasmosis-associated miscarriage with maternal infection four months prior to conception

BACKGROUND

We report a case of fatal congenital toxoplasmosis with maternal infection dated four months before pregnancy in the absence of any specific immunosuppressive condition.

CASE

Ms. D. experienced submaxillary lymphadenitis in February 2018. The medical workup performed revealed an acute T. gondii infection. She became pregnant in June 2018 while she still had adenopathy. The second obstetrical ultrasound, performed at 16 weeks of pregnancy, revealed a fetal death. The research for T. gondii by PCR was positive in the products of conception.

CONCLUSION

Diagnosis of toxoplasmosis should be discussed in case of miscarriage with lymphadenitis. As lymph nodes in T. gondii infection could be responsible for iterative release of parasites and fetal death, symptomatic toxoplasmosis should be treated in women of childbearing age.

Toxoplasmosis screening during pregnancy in France: Opinion of an expert panel for the CNGOF

Prenatal screening to prevent congenital toxoplasmosis as performed in France for several decades has been questioned in view of the decreasing incidence of this infection and the cost of testing. The French College of Obstetrics and Gynecology mandated a multidisciplinary panel of experts to perform a reassessment of the screening program in accordance with international good practice. In France, about 70% of pregnant women are not immune to T. gondii, and 0.2-0.25% become infected during pregnancy. The risk of maternal-fetal transmission of infection is on average 25-29% and depends greatly on the gestational age at seroconversion. In case of fetal transmission, the outcome is livebirth in 95% of cases, with latent congenital toxoplasmosis in 90% of cases and symptomatic forms in 10% of cases, of which 1/3 are severe and 2/3 moderate. Biological techniques have satisfactory performance regarding serologies for the diagnosis of maternal infections and PCR on amniotic fluid for the prenatal diagnosis of congenital toxoplasmosis. Primary prevention of toxoplasmosis is based on hygiene measures that are relatively simple, but poorly implemented. In case of maternal seroconversion, there is a strong case for prenatal prophylactic treatment as soon as possible (ideally within 3 weeks of seroconversion), spiramycin before 14 weeks of gestation (WG), and with a tendency to superiority of the pyrimethamine/sulfadiazine association over spiramycin beyond 14 W G, in order to reduce the risk of symptomatic congenital toxoplasmosis. In case of congenital toxoplasmosis, prompt initiation of treatment reduces the occurrence of cerebral signs and symptoms, as well as retinal lesions. Several medico-economic evaluations of the French toxoplasmosis screening program have been conducted including an individual cost-effectiveness approach with decision analysis which concluded on the profitability of prenatal screening as carried out in France (monthly surveillance of seronegative women, prenatal treatment in case of seroconversion, termination of pregnancy in severe forms). Though most international societies do not recommend systematic screening for mainly financial reasons, if congenital toxoplasmosis appears benign in France today, it is probably thanks to screening and the possibility of early treatment of fetuses and/or newborns. Thus, the panel recommends continuing for now the program in France for prevention of congenital toxoplasmosis.

[Suspected toxoplasmosis in pregnancy]

Primary infection with Toxoplasma gondii in pregnant women can lead to vertical transmission of the parasites resulting in congenital toxoplasmosis. The frequency of foetal infection increases with gestational age at maternal infection, but the risk of developing clinical sequelae decreases. Data on antiparasitic treatment suggest, that maternal treatment reduces the risk of serious neurological sequelae or death in congenitally infected offspring. Aspects of diagnosis and antimicrobial treatment of T. gondii infection during pregnancy are summarised in this review.

[Congenital Toxoplasmosis and CMV in Switzerland in 2019]

Epidemiological trends in congenital toxoplasmosis and CMV are extremely divergent. While there were only 39 cases of congenital toxoplasmosis in Switzerland between 1982 and 2015, there was an equivalent number of cases of congenital CMV, 38 in total, in 2017 alone. Serological screening for toxoplasmosis was logically abandoned in Switzerland in 2008. Regarding CMV, there is no recommendation for serological screening or neonatal screening in Switzerland, whereas early diagnosis can improve prognosis through the rapid initiation of antiviral treatment. The epidemiological data generated by sentinel surveillance of congenital CMV infections in Switzerland may or may not justify such a measure in our country in the future.

Basic heel prick test: inclusion of screening, diagnosis and criteria for early confirmation of congenital infection by Toxoplasma gondii

Toxoplasma gondii can cross the placental barrier, causing fetal infection with potentially severe sequelae. The aim of this study was to evaluate whether the serological screening for toxoplasmosis should be included in the basic neonatal heel prick test in order to establish criteria for the confirmation and/or exclusion of the diagnosis of congenital infection in newborns treated at three public health units in the metropolitan region of Goiania, Goias State, Brazil. Blood samples were collected on filter paper from newborns and later, peripheral blood samples from the mothers and their respective children were obtained to confirm or exclude the diagnosis of suspected congenital infection, by means of an enzyme-linked immunosorbent assay (IgM and IgG) and a polymerase chain reaction assay. From a total of 1,159 blood samples collected on filter paper, 43.92% were reactive to IgG and 0.17% to anti-T. gondii IgM and IgG. One hundred and twenty-seven paired samples (mother and child) were collected following consensual protocols for peripheral blood collection. Results obtained from the filter paper and peripheral blood of the newborns were 90.55% concordant. A comparison of the mother and child blood test results showed agreement regarding the detection of IgG in 90.48% of the samples. The parasite DNA was detected in the peripheral blood of one child. In view of the results obtained in this study, the inclusion of the serological screening for toxoplasmosis in the newborn heel prick test proved to be effective for the early detection of congenital T. gondii infection.

Rubella virus, Toxoplasma gondii and Treponema pallidum congenital infections among full term delivered women in an urban area of Tanzania: a call for improved antenatal care

BACKGROUND

A significant proportion of newborns in the developing countries are born with congenital anomalies.

OBJECTIVE

This study investigated congenital infections due to Rubella virus, Toxoplasma gondii, Treponema pallidum among presumed normal neonates from full term pregnant women in Mwanza, Tanzania.

METHODS

Sera from mothers were tested for Treponema pallidum and Toxoplasma gondii infection while newborns from mothers with acute infections were tested for T. pallidum and T. gondii, and all newborns were tested for Rubella IgM antibodies.

RESULTS

A total of 13/300 (4.3 %) mothers had T. pallidum antibodies with 3 of them having acute infection. Two (0.7 %) of the newborns from mothers with acute infection were confirmed to have congenital syphilis. Regarding toxoplasmosis, 92/300 (30.7 %) mothers were IgG seropositive and 7 had borderline positivity, with only 1/99 (1%) being IgM seropositive who delivered IgM seronegative neonate. Only 1/300 (0.3 %) newborn had rubella IgM antibodies indicating congenital rubella infection.

CONCLUSION

Based on these results, it is estimated that in Mwanza city in every 100,000 live births about 300 and 600 newborns have congenital rubella and syphilis infections, respectively. Rubella virus and T. pallidum are likely to be among common causes of congenital infections in developing countries.

Congenital central toxoplasmic chorioretinitis - case study

Congenital toxoplasmosis is a globally spread infectious disease caused by transplacental transmission of an intracellular parasitic protozoan Toxoplasma gondii. The infection can cause serious multi-organ complications, and in the case of vertical transmission, can lead up to fetal death - depending on the stage of pregnancy at the time of infection and the overall condition of the mothers immune system. Chorioretinitis, hydrocephalus and intracranial calcifications are a typical triad of symptoms associated with the disease. Toxoplasmic chorioretinitis in particular is the most common ocular manifestation. If the central retina is affected, it can cause a severe impairment of central visual acuity or lead up to blindness in the child. Prenatal screening of this disease is presently voluntary in the Czech Republic. This article reports on a case study of a toxoplasmic chorioretinitis in a newborn child observed from the active stage and the development of the affected retina over time. Further is also reported on the diagnostics and the treatment of multi-organ complications which occurred in this patient. Ophthalmologic examination was performed after diagnosis of hydrocephalus, which revealed severe changes of retina. Hydrocephalus was then properly treated. An overview of the diagnostic and therapeutic methods and the screening options available in the Czech Republic compare with other countries is also presented in the report. Key words: congenital toxoplasmosis, chorioretinitis, multi-organ complications, screening, hydrocephalus.

Usefulness of paired samples for the Serodiagnosis of toxoplasmosis infection in a tertiary teaching Hospital in Malaysia

BACKGROUND

Accurate diagnosis of Toxoplasma gondii (T. gondii) infection remains elusive and requires a comprehensive assessment through laboratory and clinical investigation. In this study, a diagnostic algorithm based on paired serum samples and clinical data was developed and evaluated.

METHODS

A total of 1267 suspected cases of Toxoplasma infection were enrolled in this study from January 2016 to December 2016. The cases were screened for anti-Toxoplasma IgM and IgG by electrochemiluminiscence immunoassay (ECLIA) method. Based on the serological profiles, all cases with first seropositive serum samples were considered as suggestive cases of Toxoplasma infection. Thus, second serum samples were obtained after an interval of 2 weeks. The diagnosis was made based on laboratory results and clinical data.

RESULTS

A total of 482 T. gondii seroreactive cases were selected. The patient's records were traced and the data were analysed. Accordingly, 152 cases were diagnosed as clinically confirmed cases; 198 cases were clinically asymptomatic and 132 cases were newborn babies or infants who did not have toxoplasmosis and only acquired passive immunity from their mothers. The paired serum algorithm allowed classifying the seroreactive cases as follows: early (0.6%), acute (1.9%), reactivation (13.5%), recent (1.5%), passive immunity from mother (27.3%) and possible congenital infections (1.2%). In addition, cases of reactivated toxoplasmosis were detected among the pregnant mothers (13/82; 15.8%), children aged above 1 year (2/8; 25.0%) and immunocompetent mothers (5/135; 3.7%). Furthermore, the application of the paired serum analysis resulted in remarkably improved treatment initiation.

CONCLUSIONS

Toxoplasmosis diagnosis and treatment can be improved through the use of paired serum diagnostic algorithm.

Detection of Toxoplasma gondii B1 gene in placenta does not prove congenital toxoplasmosis

BACKGROUND

Congenital toxoplasmosis is an important disease that occurs when pregnant women become infected with Toxoplasma gondii during pregnancy. The aim of this study was to investigate the presence of T. gondii B1 gene in placental tissues of IgM seronegative women.

MATERIALS AND METHODS

In this research, chronic toxoplasmosis was identified through examination of blood samples in a group of pregnant women by anti-Toxoplasma IgG and IgM ELISA and nested-PCR techniques. IgG avidity test was used to estimate the onset of infection in some pregnant women with chronic infection. After delivery, some umbilical cord and neonatal blood were tested by anti-Toxoplasma IgM ELISA, and also the B1 gene of T. gondii was investigated in their placental tissue by nested-PCR. Some factors such as blood sampling time and some clinical symptoms experienced during pregnancy were recorded.

RESULTS

One hundred and sixty seven out of 653 (25.6%) pregnant women were positive for anti-Toxoplasma IgG. Of them, 165 (98.8%) were negative for anti-T. gondii IgM. Six out of 10 (60%) placental tissues from IgG seropositive, IgM seronegative women were positive for T. gondii B1 gene, while anti-Toxoplasma IgM was negative in the umbilical cord and neonatal blood samples. The results of IgG avidity test showed low avidity in one and high avidity in two women's samples. The B1 gene was not found in the blood samples of any of the six mothers. The most symptoms experienced during pregnancy were headache and nausea.

CONCLUSION

The detection of B1 gene in placental tissues of the healthy newborn infants reiterates that presence of T. gondii in the placenta does not always result in congenital toxoplasmosis.

Wnt-Spectrum Vitreoretinopathy Masquerading as Congenital Toxoplasmosis

Wnt-spectrum vitreoretinopathies are a group of rare inherited disorders of retinal angiogenesis that include familial exudative vitreoretinopathy/Norrie disease and are most commonly autosomal dominant; however, they can rarely present with other inheritance patterns that are more difficult to diagnose. The authors describe a case of an uncle misdiagnosed as congenital toxoplasmosis for decades and his 2-month-old nephew presenting with bilateral retinal detachments. Genetic analysis revealed an NDP gene mutation in the child and the uncle, as well as heterozygosity of the mother confirming a Wnt-spectrum vitreoretinopathy. This report describes the evaluation, diagnosis, and importance of early laser stabilization of this disorder. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:446-450.].

Prenatal toxoplasmosis antibody and childhood autism

There is evidence that some maternal infections during the prenatal period are associated with neurodevelopmental disorders, such as childhood autism. However, the association between autism and Toxoplasma gondii (T. gondii), an intracellular parasite, remains unclear. The authors examined whether serologically confirmed maternal antibodies to T. gondii are associated with odds of childhood autism in offspring. The study is based on a nested case-control design of a large national birth cohort (N = 1.2 million) and the national psychiatric registries in Finland. There were 874 cases of childhood autism and controls matched 1:1 on date of birth, sex, birthplace and residence in Finland. Maternal sera were prospectively assayed from a national biobank for T. gondii IgM and IgG antibodies; IgG avidity analyses were also performed. High maternal T. gondii IgM antibody was associated with a significantly decreased odds of childhood autism. Low maternal T. gondii IgG antibody was associated with increased offspring odds of autism. In women with high T. gondii IgM antibodies, the IgG avidity was high for both cases and controls, with the exception of three controls. The findings suggest that the relationship between maternal T. gondii antibodies and odds of childhood autism may be related to the immune response to this pathogen or the overall activation of the immune system. Autism Res 2017, 10: 769-777. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

[TORCH syndrome: Rational approach of pre and post natal diagnosis and treatment. Recommendations of the Advisory Committee on Neonatal Infections Sociedad Chilena de Infectología, 2016]

There is a lot of bacterial, viral or parasite infections who are able to be transmitted vertically from the mother to the fetus or newborn which implicates an enormous risk for it. The TORCH acronym is used universally to refer to a fetus or newborn which presents clinical features compatible with a vertically acquired infection and allows a rational diagnostic and therapeutic approach. The traditional "TORCH test" is nowadays considered not appropriate and it has been replaced for specific test for specific pathogens under well defined circumstances. The present document reviews the general characteristics, epidemiology, pathogenesis, diagnostic and therapeutic options for the most frequently involved pathogens in the fetus or newborn with TORCH suspicion.

Performance of Polymerase Chain Reaction Analysis of the Amniotic Fluid of Pregnant Women for Diagnosis of Congenital Toxoplasmosis: A Systematic Review and Meta-Analysis

Introduction

Congenital infection caused by Toxoplasma gondii can cause serious damage that can be diagnosed in utero or at birth, although most infants are asymptomatic at birth. Prenatal diagnosis of congenital toxoplasmosis considerably improves the prognosis and outcome for infected infants. For this reason, an assay for the quick, sensitive, and safe diagnosis of fetal toxoplasmosis is desirable.

Goal

To systematically review the performance of polymerase chain reaction (PCR) analysis of the amniotic fluid of pregnant women with recent serological toxoplasmosis diagnoses for the diagnosis of fetal toxoplasmosis.

Method

A systematic literature review was conducted via a search of electronic databases; the literature included primary studies of the diagnostic accuracy of PCR analysis of amniotic fluid from pregnant women who seroconverted during pregnancy. The PCR test was compared to a gold standard for diagnosis.

Results

A total of 1.269 summaries were obtained from the electronic database and reviewed, and 20 studies, comprising 4.171 samples, met the established inclusion criteria and were included in the review. The following results were obtained: studies about PCR assays for fetal toxoplasmosis are generally susceptible to bias; reports of the tests’ use lack critical information; the protocols varied among studies; the heterogeneity among studies was concentrated in the tests’ sensitivity; there was evidence that the sensitivity of the tests increases with time, as represented by the trimester; and there was more heterogeneity among studies in which there was more time between maternal diagnosis and fetal testing. The sensitivity of the method, if performed up to five weeks after maternal diagnosis, was 87% and specificity was 99%.

Conclusion

The global sensitivity heterogeneity of the PCR test in this review was 66.5% (I²). The tests show low evidence of heterogeneity with a sensitivity of 87% and specificity of 99% when performed up to five weeks after maternal diagnosis. The test has a known performance and could be recommended for use up to five weeks after maternal diagnosis, when there is suspicion of fetal toxoplasmosis.

Toxoplasmosis, Parvovirus, and Cytomegalovirus in Pregnancy

There are several infections in adults that warrant special consideration in pregnant women given the potential fetal consequences. Among these are toxoplasmosis, parvovirus B19, and cytomegalovirus. These infections have an important impact on the developing fetus, depending on the timing of infection. This article reviews the modes of transmission as well as maternal and neonatal effects of each of these infections. In addition, the article outlines recommended testing, fetal surveillance, and treatment where indicated.

Prenatal and Early Postnatal Diagnosis of Congenital Toxoplasmosis in a Setting With No Systematic Screening in Pregnancy

To determine the risk of congenital toxoplasmosis (CT) and provide early (pre- or postnatal) identification of cases of CT in the absence of systematic screening in pregnancy.I n the presented cross-sectional study, serological criteria were used to date Toxoplasma gondii infection versus conception in 80 pregnant women with fetal abnormalities or referred to as suspected of acute infection, and in 16 women after delivery of symptomatic neonates. A combination of serological, molecular (qPCR), and biological (bioassay) methods was used for prenatal and/or postnatal diagnosis of CT. Most (77.5%) pregnant women were examined in advanced pregnancy. Of all the examined seropositive women (n = 90), infection could not be ruled out to have occurred during pregnancy in 93.3%, of which the majority (69%) was dated to the periconceptual period. CT was diagnosed in 25 cases, of which 17 prenatally and 8 postnatally. Molecular diagnosis proved superior, but the diagnosis of CT based on bioassay in 7 instances and by Western blot in 2 neonates shows that other methods remain indispensable. In the absence of systematic screening in pregnancy, maternal infection is often diagnosed late, or even only when fetal/neonatal infection is suspected. In such situations, use of a complex algorithm involving a combination of serological, biological, and molecular methods allows for prenatal and/or early postnatal diagnosis of CT, but lacks the preventive capacity provided by early maternal treatment.

The IgG avidity value for the prediction of Toxoplasma gondii infection in the amniotic fluid

Primary Toxoplasma gondii (T. gondii) infection during pregnancy may lead to congenital toxoplasmosis. Maternal screening using T. gondii IgG avidity measurement and multiplex nested PCR was performed. The aim of this prospective cohort study was to determine a cut-off value of IgG avidity index (AI) for the prediction of the presence of T. gondii DNA in the amniotic fluid. One hundred thirty-nine women with positive or equivocal tests for IgM underwent both serum IgG avidity measurement and PCR analysis for the amniotic fluid. Nine had positive PCR results, and three of them were diagnosed as having congenital infection. A cut-off value of IgG AI was determined using receiver operating characteristic analysis. IgG AI (mean 13%) in women with positive PCR results was significantly lower than that (39%) in women with negative results. A cut-off value of <25% IgG AI yields the best results with 77.8% sensitivity and 81.5% specificity for the presence of T. gondii DNA in the amniotic fluid. None of women with IgG AI of ≥30% had a positive PCR result or congenital infection. This study firstly demonstrated that a cut-off value of 25-30% IgG AI might be useful for the prediction of the presence of T. gondii DNA in the amniotic fluid and congenital infection.

Congenital toxoplasmosis: an uncommon disease in Thailand

BACKGROUND

The seroprevalence of toxoplasma antibodies in pregnant women and the prevalence of congenital infection differ widely between countries. A few cases of congenital toxoplasmosis diagnosed after the neonatal period, with long-term sequelae, have been reported in Thailand. No data on the prevalence of congenital toxoplasmosis have been documented and no screening for toxoplasmosis during pregnancy has been undertaken in Thailand.

SUBJECTS AND METHODS

A questionnaire enquiring about cases of congenital toxoplasmosis during 1995-2013 was distributed to paediatricians in referral and university hospitals in Thailand and the responses were analysed. Specific toxoplasma IgM antibody and clinical features were used for diagnosis.

RESULTS

There were 20 cases - 13 most likely and seven suspected cases of congenital toxoplasmosis. Most patients had systemic manifestations, but only 25% of diagnosed patients exhibited the classic triad of hydrocephalus, cerebral calcification and chorioretinitis. One of the five deceased patients lived beyond the age of 13 years and died of a pulmonary infection. All 15 surviving cases developed deafness, visual impairment or developmental delay.

CONCLUSIONS

Twenty cases of congenital toxoplasmosis are reported. Delayed diagnosis and treatment resulted in a poor outcome. The prevention of toxoplasmosis in pregnant women and prompt diagnosis and appropriate treatment of congenital toxoplasmosis should be a priority in order to prevent a poor outcome in infected children.

Congenital Toxoplasmosis: A Review

Acute infection of toxoplasmosis during pregnancy is detrimental to the developing fetus. In the United States, approximately 1 in 10,000 live births are affected by congenital toxoplasmosis. Although multifactorial in etiology, maternal infection is primarily attributed to the consumption of contaminated meat or water. Infection and transmission to the fetus may result in devastating neurologic impairment. Screening methods for all pregnant women should be implemented in routine prenatal care. This article will highlight the inherent dangers of congenital toxoplasmosis, while including general care of the fetus for prevention of transmission, medical management, and long-term outcomes.

Multidisciplinary approach to congenital Toxoplasma infection: an Italian nationwide survey

Italy provides a free voluntary serological screening for toxoplasmosis in pregnancy supported by public health system, as there is an estimated congenital toxoplasmosis rate of 1-2/10,000. The aim of this study was to make an inventory of diagnostic and therapeutic protocols in use in Italy in the absence of a national guideline. A semistructured questionnaire was distributed to AMCLI (Italian Association of Clinical Microbiologists) members who were asked to involve other specialists to fill in the form. Data from 26 centers show: a) a general use of the IgG avidity test to solve diagnosis in IgG/IgM positive, pregnant women; b) a widespread attitude to spyramicin antenatal treatment in suspected, unconfirmed maternal infection; c) avoidance of invasive antenatal diagnosis only in suspected early or late (>24 weeks), even confirmed, maternal infection d) fetal diagnosis performed by PCR assays on amniotic fluid; e) variability of both indications and dosage of pyrimethamine-sulfadiazine (P-S) as fetal treatment; f) use of comparative mother and newborn IgG/IgM Immuneblot in most centers; g) no diagnostic tests performed on placenta and cord blood; h) spyramicin is no longer used in congenital infections; i) no P-S-based treatment for children at high risk of congenital infection (late maternal infection) in the absence of diagnosis. As there is the opportunity to test pregnant women for Toxoplasma gondii infection in Italy free of charge, standardized diagnostic and therapeutic national guidelines would focus on a more uniform approach.

Assessment of laboratory methods used in the diagnosis of congenital toxoplasmosis after maternal treatment with spiramycin in pregnancy

BACKGROUND

The different laboratory methods used in the diagnosis of congenital toxoplasmosis have variable sensitivity and specificity. There is no evidence to prove that maternal treatment reduces the risk of fetal infection. The purpose of this study was to assess methods for the confirmation of congenital toxoplasmosis after maternal treatment with spiramycin during pregnancy, and to evaluate the effect of this treatment on clinical manifestations of the disease in newborns (NB).

METHODS

This was a community-based, cross-sectional study of acute toxoplasmosis in newborns at risk of acquiring congenital infection. Participating newborns were born in the Clinical Hospital Maternity Ward of the Federal University of Goiás. Eligible participants were divided into 2 groups: group 1 consisted of 44 newborns born to mothers treated with spiramycin during pregnancy and group 2 consisted of 24 newborns born to mothers not treated with spiramycin during pregnancy because the diagnosis of toxoplasmosis was not performed. The sensitivity and specifity of PCR for T. gondii DNA in peripheral blood and serological testing for specific anti-T. gondii IgM and IgA, and the effects of maternal spiramycin treatment on these parameters, were determined by associating test results with clinical manifestations of disease.

RESULTS

The sensitivity of the markers (T. gondii DNA detected by PCR, and the presence of specific anti-T. gondii IgM and IgA) for congenital toxoplasmosis was higher in group 2 than in group 1 (31.6, 68.4, 36.8% and 3.7, 25.9, 11.1% respectively). Even with a low PCR sensitivity, the group 2 results indicate the importance of developing new techniques for the diagnosis of congenital toxoplasmosis in newborns. Within group 1, 70.4% of the infected newborns were asymptomatic and, in group 2, 68.4% showed clinical manifestations of congenital toxoplasmosis.

CONCLUSIONS

The higher proportion of infants without clinical symptoms in group 1 (70.4%) suggests the maternal treatment with spiramycin delays fetal infection, reducing the clinical sequelae of the disease in newborns. Given the low sensitivity of the tests used, when there is suspicion of congenital transmission several serological and parasitological tests are required in order to confirm or exclude congenital toxoplasmosis in newborns.

Congenital toxoplasmosis presenting with fetal atrial flutter after maternal ingestion of infected moose meat

Consumption of undercooked game meat during pregnancy is considered a risk factor for congenital toxoplasmosis, but cases definitively linking ingestion of infected meat to clinical disease are lacking. We report a confirmed case of congenital toxoplasmosis identified because of atrial flutter in the fetus and linked to maternal consumption of Toxoplasma gondii PCR-positive moose meat.

The performance of four molecular methods for the laboratory diagnosis of congenital toxoplasmosis in amniotic fluid samples

INTRODUCTION

Toxoplasmosis may be life-threatening in fetuses and in immune-deficient patients. Conventional laboratory diagnosis of toxoplasmosis is based on the presence of IgM and IgG anti-Toxoplasma gondii antibodies; however, molecular techniques have emerged as alternative tools due to their increased sensitivity. The aim of this study was to compare the performance of 4 PCR-based methods for the laboratory diagnosis of toxoplasmosis. One hundred pregnant women who seroconverted during pregnancy were included in the study. The definition of cases was based on a 12-month follow-up of the infants.

METHODS

Amniotic fluid samples were submitted to DNA extraction and amplification by the following 4 Toxoplasma techniques performed with parasite B1 gene primers: conventional PCR, nested-PCR, multiplex-nested-PCR, and real-time PCR. Seven parameters were analyzed, sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), negative likelihood ratio (NLR) and efficiency (Ef).

RESULTS

Fifty-nine of the 100 infants had toxoplasmosis; 42 (71.2%) had IgM antibodies at birth but were asymptomatic, and the remaining 17 cases had non-detectable IgM antibodies but high IgG antibody titers that were associated with retinochoroiditis in 8 (13.5%) cases, abnormal cranial ultrasound in 5 (8.5%) cases, and signs/symptoms suggestive of infection in 4 (6.8%) cases. The conventional PCR assay detected 50 cases (9 false-negatives), nested-PCR detected 58 cases (1 false-negative and 4 false-positives), multiplex-nested-PCR detected 57 cases (2 false-negatives), and real-time-PCR detected 58 cases (1 false-negative).

CONCLUSIONS

The real-time PCR assay was the best-performing technique based on the parameters of Se (98.3%), Sp (100%), PPV (100%), NPV (97.6%), PLR (∞), NLR (0.017), and Ef (99%).

[Toxoplasmosis in pregnancy - questions in clinical practice]

Toxoplasmosis acquired during pregnancy is a serious disease that may significantly affect fetal development and cause irreversible or therapeutically hardly influenced damage to the newborn. Early and correct diagnosis of the disease in the mother is essential for determining prognosis and further diagnostic and therapeutic procedures. The case study combines a number of factors to be encountered in clinical practice which may complicate diagnostic considerations. One of them is the existence of a rare phenomenon of reinfection - its possible effects on prenatal screening and other interpretations of such findings. Another problem is the evaluation of the origin of sonographically confirmed fetopathy in relation to Toxoplasma etiology and the choice of next steps that should follow in this situation. Finally, the text discusses the selection of postnatal examinations so that they sufficiently contribute to decision-making about the newborn's treatment initiation.