Avascular necrosis of bone in patients with human immunodeficiency virus infection: report of 6 cases and review of the literature.

In 1998 and 1999, we diagnosed avascular necrosis of bone in 6 patients in our human immunodeficiency virus clinic practice, an incidence of 0.45%, which is 45 times greater than would be expected in the general population. Antiphospholipid antibodies and hyperlipidemia secondary to protease inhibitor therapy have been implicated as possible etiologies; however, these abnormalities cannot explain all cases of avascular necrosis of bone reported in patients with human immunodeficiency virus infection.