[Isolation of an acid-alcohol resistant bacillus (BAAR) in the febrile HIV infected patients: Mycobacterium tuberculosis (MT) or Mycobacterium avium complex (MAC)?].

The detection of BAAR in HIV infected patients with CD4 < 100/mm3 and with an infectious syndrome urge on beginning an effective treatment against Mycobacterium tuberculosis and/or Mycobacterium avium Complex, before the results of the culture are known. Our purpose was to search clinical and biological features to angle directly the diagnosis towards a tuberculosis or not, and to start the most suitable treatment. This retrospective study, from 1986 to 1993, stated on 54 patients who had at least one sample with positive BAAR (blood, marrow, stools, sputum or urine cultures). From these cultures, MAC was isolated on 37 patients and BK on 17. The both groups were similar for age, sex, risk factor, number of opportunistic infections, delay between the date of AIDS and the discovery of a positive BAAR, and Ag p24. However, a significant difference in favor of a MAC disease exists regarding about: disseminated infections (92% vs 53%), digestive troubles (57% vs 23.5%), anterior or concomitant CMV infection (49% vs 9%), isolation of BAAR in blood culture (54% vs 20%) or in stools culture (76% vs 33%), leucopenia (2850/mm3 +/- 1520 vs 4124/mm3 +/- 2232), anémia (Hb 9.1 g/dl +/- 1.5 vs 10.1 g/dl +/- 1.6). The univariated analysis of results allowed us to conclude that the presence of one among those parameters must induce the prescription of a suitable treatment against MAC.