Mycobacterium avium complex causing endobronchial disease in AIDS patients after partial immune restoration.

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.