Cytometric analysis of blood cells from malaria-infected patients and in vitro infected blood.

Blood samples from malaria-infected patients and from in vitro culture were analyzed using the H*1 hematology analyzer. An attempt to find a hematologic parameter for detecting the malaria infection and to characterize the pathophysiological changes of red cells was made. The study included 18 malaria-infected patients (10 with Plasmodium falciparum and 8 with Plasmodium vivax) and 52 normal, healthy volunteers. Increased young large lymphocyte or large unstained cell count (LUC over 3%) in the peripheral blood of malaria-infected patients was evidence for malaria infection. Increased population dispersions of red cell volume (red cell distribution width: RDW) and intraerythrocytic hemoglobin concentration (hemoglobin distribution width: HDW) were demonstrated both in clinical samples and cultured blood. The increased RDW correlated with an increased percentage of macrocytes (r = 0.64, P = 0.004). Comparison of HDW and percentage of hypochromic red cells between the clinical specimen and the cultured blood supports the finding that changes in red cell hemoglobin concentration were mainly due to the response of the patient to malaria infection and partly due to the effect of malaria parasites on the red cells.