[The bone marrow in human HIV infection. A bioptic study of 125 cases].

Bone marrow biopsies from 125 patients at different stages of HIV infection were examined and the histopathological changes are described. Indications for biopsy included peripheral blood abnormalities, search for opportunistic pathogens, a suspected lymphoma or evaluation of its progression. Common histopathological features, suggestive of HIV infection but non-pathognomonic, were: severe hypercellularity (43.2%), myelodysplasia (74.4%), plasmocytosis (86.4%), and lymphocytic (36.8%) and histiocytic infiltrates with or without granulomas (20%). Reticular fibrosis (58.6%), iron deposits (59.2%), vascular congestion and mucoid degeneration of fat (18.4%) were frequently observed. Hypoplasia was usually a late-occurring event and/or may have been iatrogenic. Opportunistic infections were detected in 8 patients: Mycobacterium avium intracellulare (4 cases), Mycobacterium tuberculosis (1 case), Cryptococcus neoformans (1 case), and Leishmania (1 case). Neoplastic complications were found in 3 patients: Burkitt's lymphoma (1 case) and Hodgkin's disease (2 cases). The pathophysiological mechanisms envisaged include the effect of HIV infection on precursor cells in the bone marrow.