BACKGROUND: Pulmonary disease due to Mycobacterium avium complex (MAC-PD) radiographically resembles that due to tuberculosis; it preferentially affects elderly white men with predisposing pulmonary disorders (PDPD). METHODS: Twenty-nine patients with MAC-PD were identified from a community-based population, and the medical records and chest roentgenograms (CRs) of six with a previously undescribed pattern of MAC-PD were reviewed. The distinctive clinical and demographic features of these six patients were identified and summarized. RESULTS: All were women who tended to be elderly. None had clinically evident PDPD. The dependent portion of the lingula or its counterpart, the middle lobe, was initially affected. Hilar adenopathy, volume loss, and cavitary disease were uniformly absent. CONCLUSIONS: To account for the distinctive features of this syndrome, we offer the hypothesis that habitual voluntary suppression of cough may have led to the development of nonspecific inflammatory processes in these poorly draining lung regions, upon which MAC-PD engrafted. We offer the term, Lady Windermere's syndrome, to describe this pattern among elderly women and to suggest that their fastidiousness may be its root cause.