Acute Trypanosoma cruzi infection is associated with anemia, thrombocytopenia, leukopenia, and bone marrow hypoplasia: reversal by nifurtimox treatment

In the present work we show that acute infect-ion of C3H mice with the CL s train of Trypanosoma cruzi is characterized by an exponential growth of par asites and high mortality accompanied by anemia, thrombocytopenia, leukopen ia, and bone marrow hypoplasia. Administration of nifurtimox, a trypanocyda l drug currently in clinical use at different days postinfection, modulates parasitemia and prevents mortality. More importantly, none of blood and bo ne marrow alterations were observed in nifurtimox-treated animals when trea tment was initiated early in infection, one or seven days postinoculation. The bone marrow alterations were characterized by a decrease in the total n umber cells as well in the number of megakaryoblasts and erythroblasts. Tra nsfer experiments of bone marrow cells from infected mice to noninfected le thally irradiated recipients revealed a poor marrow-repopulating activity. The colony forming units-spleen assay confirmed the depression of committed clonal progenitors cells and revealed a decreased number of granulocyte/ma crophage, megacariocyte and erythrocyte colonies, In summary, this is the f irst report showing that acute T. cruzi infection results in profound alter ations of the hematopoietic system and that these alterations can be preven ted by nifurtimox treatment. (C) 2000 Editions scientifiques et medicales E lsevier SAS.