Clinicopathological and immunological studies of pulmonary tuberculosis in the aged

Two cases of aged patients with pulmonary tuberculosis were presented. Their clinical, roentgenological and pathological findings were far different from those of typical pulmonary tuberculosis in adult. To clarify the causes of this atypical manifestation in the aged patients, clinical and immunological characteristics of newly diagnosed tuberculosis in 33 cases of elderly patients, were compared with those in 23 cases of teens and 30 cases of twentieth, and the results were summarized as follows: 1) An extensive distribution of tram lines and acinar patterns was observed radiographically in the presented two cases. These radiographical findings were indistinguishable from chronic airway infections. In addition, there were little or no cavitary changes in these lesions. 2) In autopsy of the first case, the lung presented many scattering foci with small caseous necrosis, around which macrophages (not epithelioid cells) and relatively few lymphocytes were seen. In drainage bronchioles of small caseous lesions a good many polymorphonuclear leukocytes were infiltrated and a few tubercle bacilli were detected. (This was different from the lesions in patients treated with corticosteroid, where numerous tubercle bacilli were proved.) Carnification was also seen around these scattered caseous foci. 3) Reactivity to Mantoux test was reduced in patients over 60 years and it was not associated with numbers of peripheral blood lymphocytes. 4) Lymphocyte blastformation by PHA was, however, significantly reduced in old patients over 70 years. The number of T lymphocytes of tuberculous patients tended to decrease with age, but it was statistically insignificant. These results described above suggested that diagnostic difficulties in elderly tuberculous patients related to their atypical roentgenologic manifestations and their increased negative Mantoux tests and negative sputum, which were mainly due to decreased immunologic responsiveness increasing with age.