Opportunist mycobacterial pulmonary infection and occupational dust exposure: An investigation in England and wales

Abstract

This paper reports a study in England and Wales in which the industrial and non-industrial dust exposures and smoking habits of those whose pulmonary disease was due to opportunist mycobacterial infection were compared with a control group of similar age and same sex whose infection was with M. tuberculosis.Of 70 males, 53 were found to be infected with M. kansasi, 9 with M. xenopi, 6 with M. intracellulare and 2 with other opportunist mycobacteria. Only 8 females were found, of whom 5 were infected with M. kansasi, and 3 with M. intracellulare.Those infected with M. kansasi were on average 6·5 years younger than those infected with other opportunist mycobacteria.There was no evidence of differences between patients infected with M. kansasi and their controls in various indices of past exposure to dust. A significantly higher proportion of patients infected with M. kansasi gave a history of current dust exposure at the time of diagnosis than patients infected with M. tuberculosis. There was an apparent association between infection with M. kansasi and exposure to the dusts of the metal grinding trades, but no association with a previous history of coal mining. The study suggests that the systematic establishment of the current occupations of all new patients suffering from disease due to M. kansasi should enable the occupations with high risk to be identified.