PULMONARY MYCOBACTERIUM-KANSASII INFECTION - COMPARISON OF THE CLINICAL-FEATURES, TREATMENT AND OUTCOME WITH PULMONARY TUBERCULOSIS

Background - In the United Kingdom Mycobacterium kansasii is the most common pulmonary non-tuberculous mycobacteria to cause disease in the non-HIV positive population. Methods - The clinical features, treatmen t, and outcome of 47 patients (13 women) of mean (SD) age 58 (17) year s with culture positive pulmonary M kansasii infection were compared w ith those of 87 patients (23 women) of mean (SD) age 57 (16) years wit h culture positive pulmonary M tuberculosis infection by review of the ir clinical and laboratory records. Each patient with M kansasii infec tion was matched for age, sex, race and, where possible, year of diagn osis with two patients with M tuberculosis infection. Results - All th ose with M kansasii infection were of white race. Haemoptysis was more common in patients infected with M kansasii but they were less likely to present as a result of an incidental chest radiograph or symptoms other than those due to mycobacterial infection. Patients with M kansa sii were also less likely to have a history of diabetes, but the frequ ency of previous chest disease and tuberculosis was similar. An alcoho l intake of > 14 units/week was less frequent in those with M kansasii , but there were no significant differences in drug history, past and present smoking habit, occupational exposures, social class, or marita l status. Patients with RI kansasii received a longer total course of antimycobacterial therapy and, in particular, extended treatment with ethambutol and rifampicin was given. There was no significant differen ce in outcome between pulmonary RI kansasii or RM tuberculosis infecti on. Conclusions - There are group differences between the clinical fea tures of the two infections but, with the possible exception of diabet es and alcohol intake, these features are unlikely to be diagnosticall y helpful. Treatment of M kansasii infection with ethambutol, isoniazi d, and rifampicin in these patients was as effective as standard regim ens given to patients infected with Ri tuberculosis.