Progressive age-related changes in pulmonary tuberculosis images and the effect of diabetes

Atypical radiologic images of pulmonary tuberculosis are common in elderly and in diabetic patients. To investigate the relationship of chest radiogra phic findings of tuberculosis to age In diabetic and nondiabetic patients, we compared the chest radiographic findings of 192 inpatients with pulmonar y tuberculosis and diabetes with those of 130 patients with pulmonary tuber culosis alone. The proportion of patients with lower lung field lesions pro gressively increased with age (r(S) = 0.89, p < 0.01), whereas the frequenc y of cavitation steadily decreased with age (r(S) = -0.79, p < 0.05). In di abetic patients, a high frequency of lower lung lesions and cavitation was observed in all age groups. We speculated that, in older patients and in di abetics, the increased alveolar oxygen pressure in the lower lobes favors d evelopment of lower lobe disease in these groups.