Infection with Leishmania (Leishmania) infantum of 0 to 18-Month-Old Children Living in a Visceral Leishmaniasis-Endemic Area in Brazil

Abstract

Abstract. The diagnosis of Leishmania (Leishmania) infantum infection in children from birth may serve as a reference for the early identification of cases that would progress to classical visceral leishmaniasis (VL) in endemic areas. This study prospectively evaluated newborns of mothers living in the municipality of Paracatu, Minas Gerais, Brazil. The infants were followed up at 6-month intervals by clinical examination, serological tests (immunofluorescence [IIF] and enzyme-linked immunosorbent assay with rK39 [ELISA-rK39]) and polymerase chain reaction (PCR) until they had completed 18 months of age. A total of 166 pregnant women were included to evaluate the possible transfer of antibodies or even congenital transmission. Twenty-two of the women tested positive by IIF, four by ELISA-rK39, and one by PCR. Three infants of the 25 women with some positive test results were also positive in the first test (one by IIF, one by ELISA-rK39, and the third by ELISA-rK39 and PCR). One hundred and sixty infants were included in the study; of these, 43 had at least one positive sample over time. However, agreement between tests was low. Follow-up of children with a positive result in the tests studied revealed no progression to classical disease within a period of 18 months. In contrast, two children with negative IIF, PCR, and ELISA-rK39 results developed classical VL at 9 and 12 months of age. In conclusion, a positive test result was variable and sometimes temporary and agreement between tests was low. Therefore, the early diagnosis of Leishmania infection was not associated with the early identification of cases that would progress to classical VL in the endemic area studied.

Visceral leishmaniasis during pregnancy: A rare case report from Greece

“…The neonate became serologically negative within six months of being born, indicating the maternal origin of the antibodies. However, data available in the literature about the contribution of serologic exams into the surveillance of the neonates are conflicting or at least discouraging [ 18 ]. In particular, infants have been described in endemic areas with positive serological markers that never progressed to classical disease, whereas others developed VL while they were serologically negative [ 18 ].…”

T‐cell tolerance as a potential effect of congenital leishmaniasis on offspring immunity

“…Third, some infants developed VL in the absence of symptoms in their mothers during pregnancy. Six such cases were identified . The common characteristic of these cases is that the infants did not reside in or visit endemic areas of leishmaniasis; however, their mothers did so before or during their pregnancy.…”

“…Parasite identification in the placenta or cord blood of subclinical cases would allow the study of the effect of the immune response on children. Although not widely practiced, this approach was utilized in a cohort study of 166 asymptomatic pregnant women living in an endemic area for VL with follow‐up of offspring for 18 months. Leishmania DNA was detected in capillary blood at different times during the study, and antibodies were detected by ELISA or indirect immunofluorescence.…”

“…Visceral leishmaniasis (VL) leads to hepatosplenomegaly, fever and bone marrow infiltration by the parasite. Asymptomatic infection also occurs, with potential chronic carriage of the parasite …”

Leishmaniose visceral infantil: relato de caso

“…A leishmaniose visceral (LV) é uma doença tropical negligenciada; vista como uma das seis doenças endêmicas consideradas como principais problemas de saúde pública em todo mundo. Apresenta incidência global estimada de 500.000 novos casos por ano e mais de 50.000 mortes anuais 1,2 . A doença ocorre em 65 países, o maior número de casos da doença, cerca de 90%, foi notificada em Bangladesh, Brasil, Etiópia, Índia, Nepal e Sudão².…”