Bone marrow morphology and proliferative activity in acquired immunodeficiency syndrome

Peripheral cytopenia has been reported in a number of patients with the acquired immunodeficiency syndrome (AIDS), but the mechanism of bone marrow (BM) failure is unclear. We have examined the BM morphology and cytokinetics of 16 untreated HIV-positive patients whose clinical condition ranged from asymptomatic (stage 1 WR and II CDC classifications) to overt AIDS (stage 6 WR and IV CDC classifications). BM aspirates and iliac crest threphine biopsies were obtained for myelogram and histologic examination, as well as for propidium iodide flow cytometric (FMC) DNA analysis. FCM data were compared with those from the BM of patients with solid tumors without BM involvement. Four patients had normal peripheral blood counts, 2 were anemic, 2 had granulocytopenia, 2 thrombocytopenia, 4 bicytopenia and 2 pancytopenia. BM cellularity was normal or increased, but only 2/16 patients had normal BM morphology. Ten patients had atypical lymphoid aggregates, relative plasmacytosis and eosinophilia, and 4 had typical myelodysplastic changes. There was no correlation between morphology and WR or CDC grade. The mean proliferative fraction (i.e. the percentage of cells in the S phase of the cell cycle) of the HIV-positive patients was 11% (range 5.5-18.3%). The mean value for the control patients was 15.1% (range 7.7-26.9%) (p less than 0.05). All patients had modal diploid DNA content without aneuploid clones. These data suggest that the mechanism of BM failure in HIV-positive patients lies in a reduced proliferative activity whose exact cause is still unclear.