Avascular Necrosis and Protease Inhibitors
INTRODUCTION
Avascular necrosis (AVN), also termed osteonecrosis, indicates ischemic death of the bone as a result of insufficient arterial blood supply. The incidence rate of AVN has been reported to be 0.135% in the general population, although incidence rates ranging 0.3-0.45% have been observed in HIV-infected (Generic Retrovir Treating HIV infection when used along with other medicines) patients. Although the exact etiology of osteonecrosis remains unclear, predisposing factors, such as HIV-related complications, an adverse event of highly active antiretroviral therapy (HAART) or a result of a HIV-associated disease, have been suggested. Additional factors associated with AVN have included corticosteroid use, alcoholism, intravenous drug use, smoking, antiphos-pholipid antibodies, hyperlipidemia, sickle cell anemia, radiation exposure and systemic lupus erythematosus. Metabolic factors, such as hyperlipidemia, have also been strongly associated with use of protease inhibitors. Regardless of the etiology, AVN has become an emerging manifestation within the HIV (Generic Zerit treating HIV infection when used in combination with other medicines) population.
Three case reports based on patients attending the ambulatory infectious disease clinic at Howard University Hospital between January 2000 and December 2000 are presented. We are not aware of any reported cases of AVN in our clinic population prior to these reported cases. Demographic and clinical information of all patients (n=160) seen in the clinic between January and December 2000 are summarized in Table 1. Risk factors common to the three reported cases include use of protease inhibitors and alcohol abuse (Table 2). Affected sites of AVN included the hip and shoulders (Table 2). The incidence of AVN within our patient population was 1.9% as compared to 0.135% in the general population. Our incidence rate is also higher than other reported rates of AVN in HIV (Generic Viramune treating HIV infection) patients. Detailed information on three cases of AVN noted in our patient population is described below. It should be noted that the testosterone levels and HIV (Zerit canadian Treating HIV infection when used in combination with other medicines) genotypes were not available.