HIV-1 infection and hematologic picture.

This review examines the wide spectrum of hematological abnormalities frequently observed in the peripheral blood and bone marrow of HIV-1 infected subjects. Several pathogenetic mechanisms have been implicated in the derangement of the hematopoietic system occurring during the course of HIV-1 infection: imbalance of the T-cell subpopulation (CD4/CD8 ratio), altered cytokine production by infected CD4+marrow cells, production of inhibitory factors by infected marrow stromal cells, antibody-mediated suppression of hematopoietic progenitors, direct infection of hematopoetic progenitors and/or precursors, and HIV-1 mediated suppression of CD34+ cell growth in the absence of a complete viral replication cycle. Each point is considered in the text, with particular attention to the mechanisms most likely to operate in the early stages of the syndrome.