Placental Malaria histological features and the burden of congenital malaria among HIV/ malaria co-infected mothers in Benin City, Edo State
Background: It is well documented that sub-Saharan Africa bears the highest burden of both malaria and HIV. Coinfection with both diseases is also well documented. Malaria parasites infecting the placenta lead to inflammation, intervillous fibrin deposition and infarction. This pathologic effect of malaria on the placental has led to the staging of placental malaria histology. These pathologic features may reflect different levels in the breach of the integrity of the placenta which may predispose to transmission of congenital malaria and possibly HIV. But few if any have examined the association of maternal placental malaria histology stages in HIV positive and negative mothers and the effects of these on their newborns (congenital malaria). Methods: Subjects were 162 newborns of HIV/malaria co-infected mothers and Controls were 162 newborns of HIV negative malaria infected mothers. Blood film for malaria parasites was done on cord blood and peripheral blood on days 1, 3 and 7 in the newborns. Maternal peripheral blood film for malaria parasite was done at delivery and placental tissue was obtained for confirmation of placental malaria by histology. Diagnosis of malaria in blood films was by light microscopy. Results: The placental malaria histology in HIV positive mothers were predominantly the chronic type (51.9%) and past type (54.6%) in HIV negative mothers respectively. Congenital malaria was significantly more in chronic types of placental malaria histology irrespective of maternal HIV status (p=0.017 in subjects and p= 0.000 in controls respectively) Conclusion: Babies born to mothers are at increased risk for congenital malaria if their placental malaria histology is of the chronic type compared to the other types (active and past) irrespective of maternal HIV status. This risk (chronic type) is highest in mothers with HIV; therefore, all babies born to HIV positive mothers should be screened for congenital malaria and managed as appropriate.