Records of patients attending the Cleveland (Ohio) Metropolitan General Hospital during the five-year period (July 1983 to June 1988) were evaluated. Patients were included in the study if they had a positive culture for Mycobacterium tuberculosis from specimens of sputum, bronchial washings, or lung biopsy. The charts and roentgenograms of 142 patients were reviewed. Of this group, 56 patients had disease localized to the upper lobes only. Further review of the latter group by two investigators, including a senior radiologist (R. Y.), categorized the extent of roentgenographic disease to segments of the right upper lobe (anterior, posterior, or apical segments) or left upper lobe (anterior or apico-posterior segments). Case histories were reviewed to ascertain the frequency of advanced age (older than 65 years), diabetes mellitus, chronic alcoholism, corticosteroid usage, and concurrent or recent malignant neoplasm.