Mycobacterium avium complex infection presenting as endobronchial lesions in immunosuppressed patients.

Infections caused by Mycobacterium avium in relatively immunocompetent hosts usually occur with isolated pulmonary involvement. Patients with the acquired immunodeficiency syndrome (AIDS) more commonly have disseminated disease. Endobronchial masses, however, have not been described with M. avium complex infections in normal or compromised hosts. We describe the cases of two patients with AIDS, both receiving zidovudine therapy, who presented with endobronchial obstruction and hilar adenopathy. Results of radiographic and endobronchial examination of these lesions suggested malignancy. Histologic and microbiologic tests, however, showed M. avium, and the lesions responded remarkably to mechanical debridement and antimycobacterial therapy.