Incidence of congenital toxoplasmosis among infants born to HIV-coinfected mothers: case series and literature review.

INTRODUCTION

There is a paucity of data on the occurrence of congenital toxoplasmosis in children born to mothers dually infected with HIV and Toxoplasma gondii.

OBJECTIVE

To evaluate aspects of the mother-infant pairs associated with vertical transmission of toxoplasmosis in women co-infected with HIV in a referral center for perinatally acquired infections in Belo Horizonte, Brazil.

METHODS

Descriptive study of HIV vertically exposed children, with congenital toxoplasmosis, followed at a referral center (cohort/Belo Horizonte). Prenatal and post-natal variables for the mother-infant pairs were evaluated. A literature review with no filtering for time and language was performed to identify reports of congenital toxoplasmosis in HIV vertically exposed children.

RESULTS

Among 2007 HIV vertically exposed children evaluated in the period from 1998 to 2011, 10 cases of congenital toxoplasmosis were identified (incidence: 0.5%, 95% confidence interval: 0.24-0.91). In searching the literature 22 additional cases in 17 reports were found. Combining the findings of our cohort with other reported cases, 50% (16/32) of congenital toxoplasmosis in HIV vertically exposed children were from Brazil. The cases of congenital toxoplasmosis in HIV vertically exposed children identified in Brazil occurred mainly in the post-Highly Active Antiretroviral Therapy era (p=0.002) and presented a lower death rate (p=0.003) than those from other countries. In the cohort/Belo Horizonte, HIV infection was identified mainly during gestation; T. gondii vertical transmission was observed in pregnant women with CD4(+)>500 cells/mm(3) and latent toxoplasmosis. High rates of ocular lesions (87.5%) and central nervous system involvement (70%) were detected.

CONCLUSIONS

The risk of vertical transmission of T. gondii in HIV-infected women is low and has been usually associated with maternal immunosuppression and elevated viral load. However, our findings of congenital toxoplasmosis in children born to HIV-infected mothers with latent toxoplasmosis and not immunosuppressed emphasize the need for careful follow-up in these cases.