Mycobacterium kansasii: A Cause of Treatable Pulmonary Disease Associated with Advanced Human Immunodeficiency Virus (HIV) Infection

Abstract

To assess the clinical features and response to therapy of Mycobacterium kansasii infection in patients with human immunodeficiency virus (HIV) infection. We reviewed the records of all patients with M. kansasii and HIV infection treated between January 1985 and June 1990. The Johns Hopkins Hospital, Baltimore, Maryland. Nineteen patients with M. kansasii and HIV infection were identified; 14 patients had exclusive pulmonary infection, 3 patients had pulmonary and extrapulmonary infection, and 2 patients had exclusive extrapulmonary infection. At the time of diagnosis of M. kansasii infection, the median CD4+ lymphocyte count was 49 cells/microL (range, 0 to 198 cells/microL), and 16 of 19 patients had a previous diagnosis of the acquired immunodeficiency syndrome (AIDS). All 17 patients with pulmonary infection presented with fever and cough of at least 2 weeks duration. Chest radiographs showed either focal upper lobe infiltrates (n = 8) or diffuse interstitial infiltrates (n = 9); 9 patients also had thin-walled cavitary lesions. Nine patients with pulmonary M. kansasii infection were treated with antituberculosis chemotherapy, with resolution of fever and respiratory symptoms, improvement of radiographic infiltrates, and sputum conversion; 1 patient with M. kansasii osteomyelitis also responded to antituberculosis therapy. Autopsies done on 3 treated patients did not reveal any evidence of M. kansasii infection. Nine patients did not receive any antituberculosis chemotherapy; 2 untreated patients developed progressive cavitary pulmonary disease and died from M. kansasii pneumonia. Mycobacterium kansasii causes serious and potentially life-threatening pulmonary disease in patients with advanced HIV-related immunosuppression. In contrast to previous reports, our findings indicate that disease produced by M. kansasii in patients with HIV infection is responsive to antituberculosis chemotherapy.