Severe falciparum malaria in children: a comparative study of 1990 and 2000 WHO criteria for clinical presentation, prognosis and intensive care in Dakar, Senegal

Abstract

The relevance of WHO criteria for severe and complicated malaria has been debated for a while, especially as regards children. Recent data led WHO experts to modify the definition of severe malaria. The objective of this study was to evaluate retrospectively the significance of the new definition on severity, lethality and intensive care distribution in children admitted with falciparum malaria (in 1997-99) to Hôpital Principal de Dakar, Senegal. We used the paediatric risk of mortality score (PRISM) to compare the 2 definitions, WHO 2000 and WHO 1990. Finally, we evaluated the impact of the new definition in terms of major therapeutic interventions (MTIs): mechanical ventilation, haemodynamic support, transfusion, haemodialysis, and the use of sedatives. Among 311 patients, the frequencies of severe malaria cases and case-fatality rates thereof were 52% (n = 161) and 17% (n = 28) respectively using the 1990 WHO criteria, and 75% (n = 233) and 12% (n = 28) using the 2000 WHO criteria. Mean PRISM score among severe cases decreased with the new definition (6.5 versus 8.6). Both definitions predicted neurological sequelae and deaths with 100% sensitivity. One or more MTIs were required in severe malaria cases in 86% (n = 139) under the 1990 criteria and 73% (n = 170) under the 2000 criteria. In this area of low and seasonal transmission, the 2000 WHO definition of severe malaria proved broader and less specific, but was easier to apply and retained the high sensitivity of the earlier definition in identifying life-threatening infections.