Programme Hospitalier Recherche Clinique, Institut Pasteur, Inserm, French Public Health Agency.

Abstract. Thrombocytopenia is a common finding in malaria, but its prognostic value has not been addressed in children. The relationship between thrombocytopenia (platelet count < 100,000/mm 3 on admission) and severity and outcome was investigated prospectively in children hospitalized with falciparum malaria in Dakar, Senegal, an area that is hypoendemic for malaria. Of 288 falciparum cases, 215 matched the 2000 World Health Organization definition of severe malaria. Median platelet counts were lower (98,000/mm 3 versus 139,000/mm 3 ; P < 0.02) among severe cases than in mild cases, and in children who died than among those who recovered (68,500/mm 3 versus 109,000/mm 3 ; P < 0.002). In severe cases, children presenting with a platelet count < 100,000/mm 3 were more likely to die (odds ratio [OR] ‫ס‬ 6.31, 95% confidence interval [CI] ‫ס‬ 2.0-26.0). Moreover, multivariate analysis identified thrombocytopenia as an independent predictor of death (OR ‫ס‬ 13.3, 95% CI ‫ס‬ 3.2-55.1). Our data show an association between thrombocytopenia and either severity or prognosis in childhood falciparum malaria.