Mycobacterium haemophilum in immunocompromised patients

Mycobacterium haemophilum, a recently described pathogen, can cause an arra y of symptoms in immunocompromised patients. To date, 90 patients with this infection have been described worldwide. We report our institution's exper ience with 23 patients who were treated from 1990 through 2000. Fourteen pa tients had undergone bone marrow transplantation, 5 were infected with huma n immunodeficiency virus, 3 had hematologic malignancies, and 1 had no know n underlying immunosupression. Clinical syndromes on presentation included skin lesions alone in 13 patients, arthritis or osteomyelitis in 4 patients , and lung disease in 6 patients. Although patients with skin or joint invo lvement had favorable outcomes, 5 of 7 patients with lung infection died. P rolonged courses of multidrug therapy are required for treatment. A diagnos is of M. haemophilum infection must be considered for any immunocompromised patient for whom acid-fast bacilli are identified in a cutaneous, synovial fluid or respiratory sample or for whom granulomas are identified in any p athological specimen.