MYCOBACTERIUM-XENOPI INFECTION MASQUERADING AS PULMONARY TUBERCULOSISIN 2 PATIENTS INFECTED WITH THE HUMAN-IMMUNODEFICIENCY-VIRUS

Mycobacterium xenopi infections have rarely been reported among patien ts infected with the human immunodeficiency virus (HIV), We recently t reated two HIV-infected men, neither of whom had a history of pulmonar y disease or AIDS-defining conditions, and who had M. xenopi lung infe ctions, Both patients presented with night sweats, cough, and pleuriti c chest pain, Chest radiographs showed an upper-lobe nodule in the fir st patient and a perihilar cavitary infiltrate in the second patient, Both patients were initially believed to have pulmonary tuberculosis a nd were treated accordingly; however, only M. xenopi grew on cultures of multiple respiratory specimens, This diagnosis was confirmed by cul tures of biopsied lung tissue from the first patient and of fluid from a peritracheal abscess in the second patient, Both patients' clinical conditions improved after multidrug therapy (isoniazid, rifampin, pyr azinamide, ethambutol, and ciprofloxacin in the first case; isoniazid, rifampin, and pyrazinamide in the second case), The second patient's condition improved despite in vitro resistance of his isolate to isoni azid and rifampin.