RESUMO
Plasmodium vivax infection has always been considered much less severe than Plasmodium falciparum and usually not associated with complications. Recently it was observed that many patients with malaria due to Plasmodium vivax also develop thrombocytopenia and other complications, once considered to be the exclusively due to Plasmodium falciparum. We carried out this study in order to find out the association of Plasmodium vivax with thrombocytopenia and to determine the presence of malaria in admitted cases of thrombocytopenia with febrile illness. This study was carried out at the pediatric ward of the Dow University of Health Sciences and Civil Hospital Karachi from Aug 2006 to Dec 2006. All patients in the age group of 1 month - 15 years and admitted in the pediatric ward with febrile illness were checked for thrombocytopenia. All study cases were also screened for the presence of malarial parasites in the thick and thin blood films and by immunochromatography [ICT]. Patients with malarial parasitemia and thrombocytopenia were included in the study. The data was then analyzed and conclusions drawn. 18/36 study cases [50%] were found to have malarial parasites in blood. 13/18 cases [72%] of malaria had thrombocytopenia and were infected with P.vivax while 2/18 cases [11%] were infected with Pl. falciparum. Six patients with malarial parasitemia showed normal platelet counts, 4 cases were due to Pl. falciparum. Platelet count was