DETECTING DISSEMINATED MYCOBACTERIUM-AVIUM COMPLEX INFECTIONS IN HIV-POSITIVE PATIENTS - THE USEFULNESS OF BONE-MARROW TREPHINE BIOPSY SPECIMENS, ASPIRATE CULTURES, AND BLOOD CULTURES

Disseminated Mycobacterium avium complex (MAC) infections are common i n patients with acquired immunodeficiency syndrome (AIDS). These patie nts frequently seek care with fever accompanied by generalized systemi c symptoms and undergo bone marrow biopsy. It is our practice to stain ail bane marrow trephine biopsy specimens from patients infected with HIV for acid-fast bacilli (AFB). We evaluated this practice by compar ing the sensitivity and turnaround time for detection of MAC by biopsy specimen staining, hone marrow aspirate culture, and blood culture. B one marrow trephine biopsy specimens with corresponding bone marrow as pirate and blood cultures from 86 HIV-positive patients were reviewed. Of the 86 patients, 30 had positive results for disseminated MAC infe ction, and all 30 of those patients had positive blood cultures. Bone marrow aspirate cultures identified 17 MAC-positive cases, and AFB sta ining of the biopsy specimen identified 9. The mean times to detection of MAC positivity were 1.1 days for AFB staining of the biopsy specim en, 19 days for bone marrow aspirate culture, and 16 days for blood cu lture. While AFB staining of biopsy specimens was the least sensitive of the detection methods, it was useful for the rapid diagnosis of dis seminated MAC infection, allowing for prompt initiation of antimycobac terial therapy in one third of patients.