Objective: To report the development of an unusual manifestation of pulmonary Mycobacterium avium complex (MAC) infection in two patients with the acquired immune-deficiency syndrome (AIDS) after the commencement of combination antiretroviral chemotherapy.
Patients: Two Caucasian males with human immunodeficiency virus (HIV) infection and CD4 lymphocyte counts <0.05 x 10x9/1 and with plasma HIV polymerase chain reaction (PCR) >100,000 copies/ml who were commenced on combination antiretroviral chemotherapy including a protease inhibitor.
Results: Both patients developed endobronchial polypoid tumours within two months of commencing antiretroviral chemotherapy. Histology demonstrated granuloma formation and acid-fast bacilli. Tissue from both patients grew M. avium. Both patients achieved significant suppression of viral replication and had significantly improved CD4 lymphocyte counts. Both required antimycobacterial therapy.
Conclusions: Endobronchial polypoid tumours due to MAC infection have only been described in HIV-infected patients receiving antiretroviral chemotherapy. A degree of restored immunity is implicated in the pathogenesis of this unusual disease.