Automated detection of haemozoin-containing monocytes for the diagnosis of malaria in microscopically negative cases during pregnancy

Plasmodium falciparum sequesters in the placenta. Cell-Dyn® automated flow cytometric haematology analysers have the capacity to detect haemozoin-containing circulating leukocytes during routine FBC analysis. In Lambaréné, Gabon, 685 FBCs of pregnant women were analysed, yielding 86.8% sensitivity and 78.5% specificity compared to microscopy. In a subset of 37 Cell-Dyn® positive but microscopy negative samples, PCR detected five positive cases. This methodology may serve as an adjunct rapid diagnostic tool for malaria during pregnancy, even in microscopically negative cases.