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.

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.

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.

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.

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.

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.

Congenital toxoplasmosis with severe neurological disease in a referral hospital in Peru. / Toxoplasmosis congénita con enfermedad neurológica severa en un hospital de referencia del Perú.

The aim of this study was to describe the epidemiological, clinical, and therapeutic characteristics of patients diagnosed with congenital toxoplasmosis (CT) with severe neurological disease. We reviewed the medical records of patients under 1 year of age with positive IgM test for Toxoplasma gondii and brain, eye, and/or hearing involvement. This study was carried out at the Instituto Nacional de Salud del Niño San Borja (INSNSB), Lima, Peru. Twenty-one patients diagnosed with CT were evaluated; 57.1% were female, and the median age at diagnosis was 3.1 months (IQR: 1.7-7.3). The main central nervous system manifestations were hydrocephalus (76.2%), intracranial calcifications (52.4%), microcephaly (42.9%), and convulsions (25.6%); the most frequent ocular manifestation was chorioretinitis (38.1%). In conclusion, 64% of CT cases had one or more manifestations of severe neurological disease.

El propósito del presente estudio fue describir las características epidemiológicas, clínicas, y terapéuticas de pacientes con diagnóstico de toxoplasmosis congénita (TC) con enfermedad neurológica severa. Se revisaron las historias clínicas de los pacientes menores de 1 año con serología IgM positiva para Toxoplasma gondii y compromiso encefálico, ocular y/o auditivo. El estudio se realizó en el Instituto Nacional de Salud del Niño San Borja (INSN-SB) en Lima, Perú. Se evaluaron a 21 pacientes con diagnóstico de TC, el 57,1% fueron del sexo femenino y la mediana de edad al momento del diagnóstico fue 3,1 meses (RIC: 1,7-7,3). Las principales manifestaciones del sistema nervioso central fueron hidrocefalia (76,2%), calcificaciones intracraneales (52,4%), microcefalia (42,9%), y convulsiones (25,6%); la manifestación ocular más frecuente fue la coriorretinitis (38,1%). En conclusión, 64% de los casos de TC tuvieron una o más manifestaciones de enfermedad neurológica severa.

Transmisión vertical de Toxoplasma gondii asociado a la edad gestacional / Vertical transmission of Toxoplasma gondii associated with gestational age

Una de las principales consecuencias de la infección por Toxoplasma gondii en mujeres embarazadas es la transmisión vertical al feto. Aunque es poco frecuente, la toxoplasmosis congénita puede causar enfermedades neurológicas u oculares graves. La infección primaria por T. gondii durante el embarazo puede tener consecuencias peligrosas, como retinocoroiditis, hidrocefalia, calcificaciones cerebrales, encefalitis, esplenomegalia, pérdida de audición, ceguera y muerte. La atención prenatal debe incluir educación sobre la prevención de la toxoplasmosis. Se trata de un estudio observacional, analítico y transversal. Se evaluaron 209 mujeres gestantes e igual número de recién nacidos; 136 de las mujeres embarazadas resultaron con infección aguda positiva a IgM. De estas 51,20% y 64,71% resultaron primoinfectadas según la determinación de IgA e IgG avidez, respectivamente. 20 de los 35 neonatos provenientes de madres primoinfectadas, adquirieron la infección congénita en el tercer trimestre de la gestación. La conciencia sobre la prevención y el control de la toxoplasmosis es baja entre las poblaciones de alto riesgo. Es necesario fortalecer la educación en salud relacionada con la prevención y el control de la toxoplasmosis en las mujeres en edad reproductiva para prevenir la transmisión vertical a sus productos de gestación y evitar los efectos negativos y hasta mortales de la inefcción por el parásito(AU)

One of the main consequences of Toxoplasma gondii infection in pregnant women is vertical transmission to the fetus. Although rare, congenital toxoplasmosis can cause serious neurological or ocular disease. Primary T. gondii infection during pregnancy can have dangerous consequences, including retinochoroiditis, hydrocephalus, cerebral calcifications, encephalitis, splenomegaly, hearing loss, blindness, and death. Prenatal care should include education on the prevention of toxoplasmosis. This is an observational, analytical and cross-sectional study. 209 pregnant women and the same number of newborns were evaluated; 136 of the pregnant women were acutely infected with IgM. Of these, 51.20% and 64.71% were primary infected according to the determination of IgA and IgG avidity, respectively. 20 of the 35 neonates from mothers with primary infection acquired the congenital infection in the third trimester of pregnancy. Awareness of toxoplasmosis prevention and control is low among high-risk populations. It is necessary to strengthen health education related to the prevention and control of toxoplasmosis in women of reproductive age to prevent vertical transmission to their gestational products and avoid the negative and even fatal effects of infection by the parasite(AU)

[Ocular toxoplasmosis in infants 0 to 12 months of age with congenital toxoplasmosis]. / Toxoplasmosis ocular en lactantes de 0 a 12 meses de edad con toxoplasmosis congénita.

BACKGROUND: Ocular toxoplasmosis (OT) is a retinochoroiditis that evolves with several episodes of inflammation and can occur both in the congenital or acquired form of the disease, Aim: To describe the frequency and clinical characteristics of OT in infants aged 0 to 12 months, children of mothers with positive serology for toxoplasmosis in the perinatal period. METHODS: Cross-sectional descriptive, ambispective study. RESULTS: Infants from 0 to 12 months of age, whose mothers had positive serology for toxoplasmosis in the perinatal period, referred to the pediatric ophthalmology service for evaluation, were admitted. Demographic variables, maternal and infant serology and the results of the ophthalmological examination were collected. Data were analyzed in SPSS v21 Results: 46.4% of 125 infants had OT, of them 67.2% were female, (p = 0.04) the median age was 6 months, 41% had IgG and IgM positive. The lesions were bilateral in 82.8%, central in 86.2%, and inactive in 81%. Retinochoroiditis was accompanied by strabismus in 41%. CONCLUSIONS: The frequency of OT in this population of infants with congenital toxoplasmosis was high. more than 80% of the eye lesions were inactive, centrally located and bilaterally involved.

Toxoplasmosis ocular en lactantes de 0 a 12 meses de edad con toxoplasmosis congénita / Ocular toxoplasmosis in infants 0 to 12 months of age with congenital toxoplasmosis

INTRODUCCIÓN: La toxoplasmosis ocular (TO) es una retinocoroiditis que evoluciona con varios episodios de inflamación y puede presentarse, tanto en la forma congénita o adquirida de la enfermedad, OBJETIVO: Describir la frecuencia y características clínicas de la TO en lactantes de 0 a 12 meses, hijos de madres con serología positiva para toxoplasmosis en el periodo perinatal. METODOLOGÍA: Estudio descriptivo transversal, ambispectivo. Ingresaron lactantes de 0 a 12 meses de edad, cuyas madres tenían serología positiva para toxoplasmosis en el periodo perinatal, remitidos al servicio de oftalmología pediátrica para evaluación. Se recogieron variables demográficas, serología materna y de los lactantes, y los resultados del examen oftalmológico. Los datos fueron analizados en SPSS-v21. RESULTADOS: El 46,4% de 125 lactantes tenían TO, de ellos, 67,2% era de sexo femenino (p = 0,04), la mediana de edad fue de 6 meses, el 41% tenía IgG e IgM positiva. Las lesiones fueron bilaterales en 82,8%, central en 86,2%, e inactivas en 81%. La retinocoroiditis se acompañó de estrabismo en 41%. CONCLUSIONES: La frecuencia de TO en esta población de lactantes con toxoplasmosis congénita, fue elevada. Más de 80% de las lesiones oculares eran inactivas, de localización central y compromiso bilateral.

BACKGROUND: Ocular toxoplasmosis (OT) is a retinochoroiditis that evolves with several episodes of inflammation and can occur both in the congenital or acquired form of the disease, AIM: To describe the frequency and clinical characteristics of OT in infants aged 0 to 12 months, children of mothers with positive serology for toxoplasmosis in the perinatal period. METHODS: Cross-sectional descriptive, ambispective study. RESULTS: Infants from 0 to 12 months of age, whose mothers had positive serology for toxoplasmosis in the perinatal period, referred to the pediatric ophthalmology service for evaluation, were admitted. Demographic variables, maternal and infant serology and the results of the ophthalmological examination were collected. Data were analyzed in SPSS v21 RESULTS: 46.4% of 125 infants had OT, of them 67.2% were female, (p = 0.04) the median age was 6 months, 41% had IgG and IgM positive. The lesions were bilateral in 82.8%, central in 86.2%, and inactive in 81%. Retinochoroiditis was accompanied by strabismus in 41%. CONCLUSIONS: The frequency of OT in this population of infants with congenital toxoplasmosis was high. more than 80% of the eye lesions were inactive, centrally located and bilaterally involved.

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.

Quality of clinical practice guidelines for gestational and congenital toxoplasmosis: A systematic review of the literature.

OBJECTIVE: To evaluate the methodological quality and transparency of the clinical practice guidelines (CPGs) for the prevention, diagnosis, and treatment of gestational and congenital toxoplasmosis (CT). METHODS: Systematic review of the literature on gestational and CT CPGs conducted in the MEDLINE, Embase, TripDatabase, Biblioteca Virtual en Salud databases and extensive manual searches in 19 CPG repositories. The characteristics of each of the guidelines were extracted using My AGREE PLUS on-line. Three reviewers assessed overall quality using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) tool. RESULTS: The combined systematic review found 8651 citations. Of them 46 full texts were reviewed, and eight documents were finally included: four toxoplasmosis CPGs, three prenatal care CPGs that included recommendations on toxoplasmosis, and one pregnancy infection guideline that also included recommendations on toxoplasmosis. The AGREE II domains found to have the highest scores were 'clarity of presentation' (85%; [37%-100%]), followed by 'scope and purpose' (73%; [33%-98%]), and 'editorial independence' (51%; [3%-94%]); the domains with the lowest scores were 'rigour of development' (36%; [11%-79%]), 'stakeholder involvement' (34%; [24%-85%]), and 'applicability' (17%; [6%-83%]). The Colombian and Spanish-Agencia de Evaluación de Tecnologías Sanitarias de Andalucía (AETSA) CPGs had the highest global AGREE II scores. Absolute interrater agreement was good to excellent. CONCLUSION: Substantial quality variation was found among CPGs, which provided recommendations in accordance with the context of the disease in the corresponding country or region. Only two of the CPGs appraised obtained a good score and are classified as 'recommended'.

Evaluation of implementation of the primary, secondary and tertiary prevention measures of the Surveillance Program of Gestational and Congenital Toxoplasmosis in the city of Londrina-PR.

Toxoplasmosis acquired during pregnancy is one that can lead to death or malformations of the foetus, and it is a complex disease to diagnose. The objective of the study was to evaluate the Surveillance Program of Gestational and Congenital Toxoplasmosis. To assess primary prevention, 424 pregnant women were interviewed regarding their knowledge of prevention measures in 2019. Secondary prevention measures were assessed, and the results of anti-Toxoplasma gondii serological tests were collected from pregnant women, from 2015 to 2018. In tertiary prevention measures, babies of mothers with a recent suspicion of T. gondii infection were screened to verify forwarding to the reference service. As a result, 45.5% (192/424) reported that they had received guidance from health professionals; 35.4% (68/192) changed their risk habits. The variables of schooling and age, having received prior guidance from health professionals and feline possession, proved to be significant when associated with the notions of preventive measures. 90.2% (17,423/19,319) of pregnant women had undergone serological tests to detect anti-T. gondii antibodies, but there was an excess in requests for tests and medication and only 40.6% (26/64) of the children were referred to the reference hospital. The Program presents positive results about the performance of serological screening in prenatal care; however, the dissemination of knowledge as for the prevention of toxoplasmosis and the request for tests need to be improved.

Evaluation of Toxoplasma gondii recombinant antigens for early diagnosis of congenital toxoplasmosis.

The performance of Toxoplasma rGra8, rMic1, and the chimeric rGra4-Gra7 antigens for early congenital toxoplasmosis (CT) diagnosis was evaluated. Sera from CT patients showed high IgG reactivity to rMic1, rGra8, and rGra4-Gra7. The seroreactivity of samples from uninfected infants was lost within 2 months of age.

PCR em tempo real no diagnóstico da toxoplasmose congênita / Real-time PCR in the diagnosis of congenital toxoplasmosis

O diagnóstico da toxoplasmose congênita apresenta limitações sendo, portanto, necessárias novas opções de exames. A análise do líquido aminiótico pela PCR em tempo real já se mostrou eficaz para confirmação da infecção fetal. No entanto, o seu desempenho em outras amostras biológicas ainda não está claro. O objetivo deste estudo é avaliar a PCR em tempo real no sangue da mãe e do recém-nascido assim como no líquido amniótico e placenta, no diagnóstico da toxoplasmose congênita. Esse é um estudo descritivo de gestantes com toxoplasmose acompanhadas no Rio de Janeiro, Brasil. Foi realizada PCR em tempo real em amostras de sangue materno, líquido amniótico, placenta e sangue dos recém-nascidos e o exame histopatológico das placentas. Também foram coletados dados clínicos e laboratoriais dos recém-nascidos. Foram acompanhadas 116 gestantes e analisadas 298 amostras. Uma (0,9%) gestante apresentou PCR positiva no sangue, três (3,5%) no líquido amniótico, uma (2,3%) na placenta e nenhum recém-nascido apresentou PCR positiva no sangue. O estudo histopatológico foi sugestivo de infecção por toxoplasmose em 24 (49%) placentas. Seis (5,2%) recém-nascidos foram diagnosticados com toxoplasmose congênita e apenas os casos com PCR positiva no líquido amniótico tinham associação do resultado da PCR com o diagnóstico de infecção congênita. Tanto as amostras de sangue materno quanto as de sangue dos recém-nascidos e placenta, não demonstraram ser promissoras no diagnóstico da toxoplasmose congênita. Novos estudos são necessários para avaliar o real papel do diagnóstico molecular em outros materiais biológicos que não o líquido amniótico.

The diagnosis of congenital toxoplasmosis has limitations so new options are needed. Real-time PCR analysis of amniotic fluid has proven effective for confirming fetal infection. However, its performance in other biological samples still needs to be determined. This study aims to evaluate the real-time PCR role in the blood of the mother and newborn as well as in the amniotic fluid and placenta, in congenital toxoplasmosis diagnosis. It is a descriptive study of pregnant women with toxoplasmosis followed in Rio de Janeiro, Brazil. Real-time PCR was performed on maternal blood, amniotic fluid, placenta, and newborn blood samples. In addition, a histopathological examination of the placentas was performed and data from the babies were collected. One hundred and sixteen pregnant women were followed and 298 samples were analyzed. One (0.9%) pregnant woman had positive PCR in the blood, three (3.5%) in the amniotic fluid, one (2.3%) in the placenta, and any newborn had positive PCR in the blood. The histopathological study suggested toxoplasmosis infection in 24 (49%) placentas. Six (5.2%) newborns were diagnosed with congenital toxoplasmosis and only the cases with positive PCR in amniotic fluid associated with the diagnosis of congenital infection. Neither maternal nor newborn blood and placenta samples have not shown promise in diagnosing congenital toxoplasmosis. Further studies are needed to evaluate the fundamental role of molecular diagnostics in others biological materials than amniotic fluid.

IgG Avidity in Samples Collected on Filter Paper: Importance of The Early Diagnosis of Congenital Toxoplasmosis.

OBJECTIVE: The purpose of the present study is to standardize and evaluate the use of the immunoglobulin G (IgG) antibody avidity test on blood samples from newborns collected on filter paper to perform the heel test aiming at its implementation in ongoing programs. METHODS: Blood samples from newborns were collected on filter paper simultaneously with the heel prick test. All samples were subjected to immunoglobulin M IgM and IgG enzyme-linked immunosorbent assays (ELISA). Peripheral blood was collected again in the traditional way and on filter paper from newborns with high IgG levels (33). Three types of techniques were performed, the standard for measuring IgG in serum, adapted for filter paper and the technique of IgG avidity in serum and on filter paper. The results of the avidity test were classified according to the Rahbari protocol. RESULTS: Among the 177 samples, 17 were collected in duplicate from the same child, 1 of peripheral blood and 1 on filter paper. In this analysis, 1 (5.88%) of the 17 samples collected in duplicate also exhibited low IgG avidity, suggesting congenital infection. In addition, the results obtained from serum and filter paper were in agreement, that is, 16 (94.12%) samples presented high avidity, with 100% agreement between the results obtained from serum and from filter paper. CONCLUSION: The results of the present study indicate that the avidity test may be another valuable method for the diagnosis of congenital toxoplasmosis in newborns.

OBJETIVO: O objetivo do presente estudo é padronizar e avaliar a utilização do teste de avidez de anticorpos imunoglobulina G (IgG) em amostras de sangue de recém-nascidos (RNs) coletadas em papel filtro para a realização do teste do pezinho visando a implementação nos programas já vigentes. MéTODOS: Foram coletadas amostras de sangue de recém-nascidos em papel filtro simultaneamente ao teste do pezinho. Em todas as amostras, foram realizados os testes imunoenzimáticos (ELISA) imunoglobulina M (IgM) e IgG. Dos RNs que apresentaram altos índices de IgG (33), foi novamente coletado sangue periférico da forma tradicional e em papel filtro. Foram realizadas técnicas padrão para a dosagem de IgG em soro, adaptadas para papel filtro, e a técnica de avidez de IgG em soro e em papel filtro. Os valores obtidos para o teste de avidez foram classificados de acordo com o protocolo de Rahbari. RESULTADOS: Dentre as 177 recoletas, em 17 amostras foi realizada a coleta simultânea de sangue periférico e papel filtro da mesma criança. Nesta análise, 1 (5,88%) das 17 amostras coletadas em duplicata obteve também baixa avidez de IgG, sugerindo infecção congênita da criança, e houve concordância entre os resultados obtidos em soro e em papel filtro: 16 (94,12%) das amostras apresentaram alta avidez, com concordância de 100% entre os resultados obtidos em soro e em papel filtro. CONCLUSãO: Os dados do presente trabalho evidenciam que o teste de avidez poderá ser mais um método valioso a ser utilizado no diagnóstico da toxoplasmose congênita em RNs.

IgG Avidity in Samples Collected on Filter Paper: Importance of The Early Diagnosis of Congenital Toxoplasmosis / Avidez de IgG em amostras coletadas em papel filtro: Importância no diagnóstico precoce da toxoplasmose congênita

Abstract Objective The purpose of the present study is to standardize and evaluate the use of the immunoglobulin G (IgG) antibody avidity test on blood samples from newborns collected on filter paper to perform the heel test aiming at its implementation in ongoing programs. Methods Blood samples from newborns were collected on filter paper simultaneously with the heel prick test. All samples were subjected to immunoglobulin M IgM and IgG enzyme-linked immunosorbent assays (ELISA). Peripheral blood was collected again in the traditional way and on filter paper from newborns with high IgG levels (33). Three types of techniques were performed, the standard for measuring IgG in serum, adapted for filter paper and the technique of IgG avidity in serum and on filter paper. The results of the avidity test were classified according to the Rahbari protocol. Results Among the 177 samples, 17 were collected in duplicate from the same child, 1 of peripheral blood and 1 on filter paper. In this analysis, 1 (5.88%) of the 17 samples collected in duplicate also exhibited low IgG avidity, suggesting congenital infection. In addition, the results obtained from serum and filter paper were in agreement, that is, 16 (94.12%) samples presented high avidity, with 100% agreement between the results obtained from serum and from filter paper. Conclusion The results of the present study indicate that the avidity test may be another valuable method for the diagnosis of congenital toxoplasmosis in newborns.

Resumo Objetivo O objetivo do presente estudo é padronizar e avaliar a utilização do teste de avidez de anticorpos imunoglobulina G (IgG) em amostras de sangue de recémnascidos (RNs) coletadas em papel filtro para a realização do teste do pezinho visando a implementação nos programas já vigentes. Métodos Foram coletadas amostras de sangue de recém-nascidos em papel filtro simultaneamente ao teste do pezinho. Em todas as amostras, foram realizados os testes imunoenzimáticos (ELISA) imunoglobulina M (IgM) e IgG. Dos RNs que apresentaram altos índices de IgG (33), foi novamente coletado sangue periférico da forma tradicional e em papel filtro. Foram realizadas técnicas padrão para a dosagem de IgG em soro, adaptadas para papel filtro, e a técnica de avidez de IgG em soro e em papel filtro. Os valores obtidos para o teste de avidez foram classificados de acordo com o protocolo de Rahbari. Resultados Dentre as 177 recoletas, em 17 amostras foi realizada a coleta simultânea de sangue periférico e papel filtro da mesma criança. Nesta análise, 1 (5,88%) das 17 amostras coletadas em duplicata obteve também baixa avidez de IgG, sugerindo infecção congênita da criança, e houve concordância entre os resultados obtidos em soro e em papel filtro: 16 (94,12%) das amostras apresentaram alta avidez, com concordância de 100% entre os resultados obtidos em soro e em papel filtro. Conclusão Os dados do presente trabalho evidenciam que o teste de avidez poderá ser mais um método valioso a ser utilizado no diagnóstico da toxoplasmose congênita em RNs.

[Congenital toxoplasmosis: the importance of adherence to guidelines and clinical implications in Colombia.] / Toxoplasmosis congénita: la importancia de la adherencia a las guías y las implicaciones clínicas en Colombia.

INTRODUCCIÓN: La toxoplasmosis congénita continúa siendo un problema de salud pública. Aun cuando existen guías plenamente divulgadas y conocidas, se observa poca implementación de ellas en algunas instituciones de salud y una inadecuada interpretación de las pruebas serológicas en las gestantes. Esto puede generar falta de captación y tratamiento en embarazadas con primoinfección por Toxoplasma gondii. CASOS CLÍNICOS: Se reportan dos casos de toxoplasmosis congénita, uno de ellos con desenlace fatal. En ambos no se siguieron las guías de práctica clínica, lo cual conllevó un diagnóstico tardío y, en consecuencia, un manejo en condiciones inapropiadas con daños graves. CONCLUSIONES: La toxoplasmosis es una infección congénita aún prevalente en algunos países, con secuelas graves, discapacidad neurológica y riesgo de daño ocular, incluso tardío. Además, existen algunas variedades de cepas de T. gondii con un comportamiento más agresivo en Latinoamérica, lo cual empeora la presentación de los casos e incluye mayor riesgo de muerte. BACKGROUND: Congenital toxoplasmosis continues to be a public health problem. Although clinical guidelines have been divulgated and are well known, they are not implemented in some health institutions, in addition of an inappropriate interpretation of the serological tests in pregnant women. This situation can lead to lack of screening and treatment in pregnant women with primary Toxoplasma gondii infection. CASE REPORTS: We report two cases of congenital toxoplasmosis, one with a fatal outcome. In both cases, the clinical guidelines were not initially followed, leading to a delayed diagnosis and, consequently, an inappropriate management in conditions with severe damage. CONCLUSIONS: Toxoplasmosis is a congenital infection still prevalent in some countries, with severe sequelae, neurological disability, and even late risk of ocular damage. ­Additionally, some varieties of the T. gondii strains have a more aggressive pattern in Latin America, worsening the clinical presentation of cases and including a high risk of death.

Comparison between Enzyme Immunoassays Performed on Samples of Dried Blood and Serum for Toxoplasmosis Prenatal Screening: Population-based Study.

OBJECTIVE: Most prenatal screening programs for toxoplasmosis use immunoassays in serum samples of pregnant women. Few studies assess the accuracy of screening tests in dried blood spots, which are of easy collection, storage, and transportation. The goals of the present study are to determine the performance and evaluate the agreement between an immunoassay of dried blood spots and a reference test in the serum of pregnant women from a population-based prenatal screening program for toxoplasmosis in Brazil. METHODS: A cross-sectional study was performed to compare the immunoassays Imunoscreen Toxoplasmose IgM and Imunoscreen Toxoplasmose IgG (Mbiolog Diagnósticos, Ltda., Contagem, Minas Gerais, Brazil)in dried blood spots with the enzyme-linked fluorescent assay (ELFA, BioMérieux S.A., Lyon, France) reference standard in the serum of pregnant women from Minas Gerais Congenital Toxoplasmosis Control Program. RESULTS: The dried blood spot test was able to discriminate positive and negative results of pregnant women when compared with the reference test, with an accuracy of 98.2% for immunoglobulin G (IgG), and of 95.8% for immunoglobulin M (IgM). CONCLUSION: Dried blood samples are easy to collect, store, and transport, and they have a good performance, making this a promising method for prenatal toxoplasmosis screening programs in countries with continental dimensions, limited resources, and a high prevalence of toxoplasmosis, as is the case of Brazil.

OBJETIVO: A maioria dos programas de triagem pré-natal para toxoplasmose utiliza imunoensaios em amostras de soro de gestantes. Poucos estudos avaliam a acurácia dos testes de triagem em amostras de sangue seco, que são de fácil coleta, armazenamento e transporte. Este estudo teve como objetivo determinar o desempenho e avaliar a concordância entre um imunoensaio em sangue seco e um teste de referência em soro de gestantes de um programa de rastreamento pré-natal de base populacional para toxoplasmose no Brasil. MéTODOS: Realizou-se um estudo transversal para comparar os imunoensaios Imunoscreen Toxoplasmose IgM e Imunoscreen Toxoplasmose IgG (Mbiolog Diagnósticos, Ltda., Contagem, Minas Gerais, Brazil) em sangue seco com o padrão de referência ensaio fluorescente ligado a enzimas (enzyme-linked fluorescent assay, ELFA, BioMérieux S.A., Lion, França) no soro de gestantes do Programa de Controle de Toxoplasmose Congênita de Minas Gerais. RESULTADOS: O exame em sangue seco foi capaz de discriminar os resultados positivos e negativos das gestantes quando comparado ao teste de referência, com acurácia de 98,2% para imunoglobulina G (IgG), e de 95,8% para imunoglobulina M (IgM). CONCLUSãO: O sangue seco apresenta bom desempenho e é uma amostra de fácil coleta, armazenamento e transporte, o que o torna um método promissor para programas de triagem pré-natal de toxoplasmose em países com dimensões continentais, recursos limitados, e alta prevalência de toxoplasmose, como é o caso do Brasil.