Assessment of International Consensus Group for Haematology smear review rules among patients with Plasmodium falciparum malaria in Johannesburg, South Africa.

A peripheral blood smear review is a useful but labour intensive adjunct to the full blood count and differential count. In this study, we retrospectively evaluated the performance of the International Consensus Group for Haematology smear review rules for detection of malaria in 153 samples with Plasmodium falciparum parasitaemia. Review rules were triggered in 132 (86.3%) samples, including all patients with severe malaria. Of the 21 false negative samples, 14 (66.7%) had haemoglobin values ≥ 10g/dl and platelets > 120x109 /l.