Real-time PCR in the diagnosis of congenital toxoplasmosis

ABSTRACT 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 new-borns 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.

Toxoplasmosis in pregnancy: a clinical, diagnostic, and epidemiological study in a referral hospital in Rio de Janeiro, Brazil

ABSTRACT Toxoplasmosis in pregnant women can cause significant morbidity and mortality in the fetus, which may be mitigated by early diagnosis and treatment. Social factors have also been related to the risk of developing the congenital form of toxoplasmosis, since some of these factors interfere directly in the quality of prenatal care. This study aimed to describe the clinical, laboratory, and epidemiological data of pregnant women diagnosed with toxoplasmosis and their newborns followed up at a referral hospital in Rio de Janeiro, Brazil. This was descriptive cohort study of 334 pregnant women with toxoplasmosis followed from May 2014 to December 2017. We conducted interviews to assess knowledge about the disease and its preventive measures, analyzed clinical and laboratory data during antenatal visits, and collected data from the newborns' medical charts. Results: This was a predominantly low-income women cohort study, with little schooling, mainly referred from public health services late in pregnancy (178; 53.3%), in the second and third trimesters (286; 85.6%). Diagnosis of acute toxoplasmosis had not been confirmed in 171 cases (51.2%). Out of 183 (54.9%) women who had initiated treatment at the original health services, 45 (24.6%) received an incorrect prescription. Seventy-two amniocenteses were performed, with positive real-time polymerase chain reaction (qPCR) in the amniotic fluid in two cases (2.8%). Congenital toxoplasmosis at birth was identified in eight newborns (5.4%). Conclusion: Late referral to specialized medical services, inadequate toxoplasmosis management at the original prenatal care services, and social vulnerabilities are contributing factors to the persistent occurrence of congenital toxoplasmosis cases.

Toxoplasmose na gestação: estudo clínico, diagnóstico e epidemiológico em um centro de referência do Rio de Janeiro / Toxoplasmosis in pregnancy: clinical, diagnostic and epidemiological study in a reference center in Rio de Janeiro

A toxoplasmose é uma zoonose de distribuição mundial, altamente prevalente no Brasil. A infecção em gestantes incorre no risco de acometimento fetal. O rastreamento sorológico durante o pré-natal é importante visto que o curso da doença é em sua maioria subclínico. O tratamento compreende o uso de espiramicina, e em caso de confirmação de infecção fetal, sulfadiazina, pirimetamina e ácido folínico. A reação em cadeia da polimerase (PCR) no líquido amniótico apresenta excelente sensibilidade e especificidade e permite estabelecer o diagnóstico fetal. Fatores sociais já foram relacionados à infecção congênita pois influenciam diretamente na qualidade da assistência pré-natal. Ainda não há um consenso nacional para a condução da toxoplasmose na gestação. O objetivo deste estudo é descrever os dados clínicos, laboratoriais e epidemiológicos de gestantes e seus recém-nascidos acompanhados em um centro de referência no Rio de Janeiro com diagnóstico de toxoplasmose. Este é um estudo descritivo de uma coorte de gestantes com toxoplasmose acompanhadas no período de maio de 2014 a dezembro de 2017. A amostra foi composta por 334 participantes. Foi realizada entrevista presencial, por telefone e revisão de prontuários, com coleta de dados sociodemográficos. Foram abordadas questões referentes ao conhecimento sobre a doença e suas formas de prevenção, além de dados clínicos e laboratoriais das gestantes e dos recém-nascidos. Observamos predomínio de uma população de baixa renda e pouca escolaridade, proveniente principalmente dos serviços públicos de saúde (178/53,29%) e encaminhadas ao centro de referência tardiamente, no segundo e terceiro trimestre de gestação (286/85,63%). O diagnóstico de toxoplasmose aguda não foi confirmado em 171 (51,20%) casos e o tratamento foi iniciado nos serviços de origem em apenas 183 (54,95%) gestantes, com prescrição incorreta em 45 (24,59%) destas. Foram realizadas 72 amniocenteses, com positividade da reação em cadeia da polimerase em tempo real (qPCR) no líquido amniótico em dois (2,78%) casos. O diagnóstico de toxoplasmose congênita ao nascimento foi identificado em oito (5,44%) recém-nascidos. O diagnóstico e o tratamento tardios da toxoplasmose na gestação foram fatores preponderantes como oportunidades perdidas na prevenção da doença congênita.

Toxoplasmosis is a zoonotic disease that occurs all over the world and is highly prevalent in Brazil. During pregnancy, it may affect the fetus. Serological screening during prenatal care is important because the course of the disease is mostly asymptomatic. Treatment includes the use of spiramycin, and, should fetal infection be confirmed, sulfadiazine, pyrimethamine and folinic acid. Polymerase chain reaction (PCR) in amniotic fluid shows excellent sensitivity and specificity and enables fetal diagnosis. Social factors have been linked to congenital infection because they have a direct impact on the quality of prenatal care. There is no national consensus for toxoplasmosis treatment during pregnancy. The objective of this study is to describe the clinical, laboratory and epidemiological data of pregnant women and their newborns with a diagnosis of toxoplasmosis treated at a referral center in Rio de Janeiro. This is a descriptive study of a cohort of pregnant women with toxoplasmosis accompanied form May 2014 to December 2017. The sample was composed of 334 participants. Face-to-face interviews and by telephone were conducted, as well as the analysis of medical records to collect sociodemographic data. Questions regarding knowledge about the disease and its types of prevention, as well as clinical and laboratory data of pregnant women and newborns were addressed. We observed a predominance of low-income population with little schooling, mainly from public health services (178/53,29%) and referred to the treatment center late in the second and third trimester of pregnancy (286/85,63%). The diagnosis of acute toxoplasmosis was not confirmed in 171 (51.20%) cases and only 183 (54,95%) pregnant women started their treatment at the first clinic they went to, with an incorrect prescription in 45 (24,59%) of these cases. A total of 72 amniocenteses were performed, with two (2,78%) positive real-time polymerase chain reaction (qPCR) in the amniotic fluid. Congenital toxoplasmosis at birth was identified in eight (5,44%) newborns. Late diagnosis and treatment of toxoplasmosis during pregnancy resulted in several missed opportunities to prevent congenital disease.

Ocular toxoplasmosis: adverse reactions to treatment in a Brazilian cohort.

Background: The purpose of this study was to estimate the frequency and describe the adverse drug reactions (ADRs) associated with the classic treatment of ocular toxoplasmosis (OT), namely sulfadiazine, pyrimethamine, corticosteroids and folinic acid. Methods: We performed a descriptive study of a prospective cohort of patients with OT treated with the classic therapy. Data were collected during medical consultations and treatment. Results: Of the 147 patients studied, 85% developed one or more ADR. Women presented more ADRs than men (95% vs 77%). Of the total reactions (n=394), 82% were mild, but we found one life-threatening event (Stevens-Johnson syndrome). The most frequent types (71%) of ADRs were gastrointestinal, skin and neurological or psychiatric. The majority of ADRs (90.3%) occurred before the second week of treatment. A third of the patients were treated for the ADR and 10% dropped out of OT treatment. Most (70%) of the ADRs were characterized as being probably caused by the drugs and may be associated with prednisone, sulfadiazine and sulfadiazine/prednisone. Six percent of ADRs were not previously described, such as taste alteration, constipation/bloating, dyspnoea, sweating and somnolence. Conclusions: Our results suggest a high rate of ADRs to OT classic treatment, which requires careful follow-up in order to identify and treat ADRs early.