Pulmonary cavitation in coalworkers' pneumoconiosis: with special reference to the cavitation in the massive fibrotic form of the disease

Abstract

1). An historical review is given of pulmonary cavitation occurring in coa'ltorkers, pith special reference to the observations of the nineteenth century Scottish physicians.2). Pulmonary cavitation may occur in association with simple pneumoconiosis. Eight such cases admitted to the Pneumoconiosis Research Unit ward between 1946 and 1952 are described. The differential diagnosis is discussed and the management and treatment are considered.3). Cavitation was discovered in 104 patients with progressive massive fibrosis admitted to the ward between the same dates. Of these 104 cases, 26 had tubercle bacilli in the sputum during life and 78 did not, although bacilli were cultured from the lungs of one of them at autopsy. Difficulty in classification may arise from the finding of nonpathogenic acid -fast bacilli in the sputum and the importance of animal inoculation is stressed.4). Fever, loss of weight, toxaemia and an elevated erythrocyte sedimentation rate are not reliable guides to the differentiation between sputum positive and negative cases of cavitated progressive massive fibrosis because the frequent non -tuberculous respiratory infections in patients with progressive massive fibrosis may affect these clinical findings.5). The prognosis for patient; in the sputum positive group of cavitated progressive massive fibrosis is poor, few surviving for more than two years after the appearance of tubercle bacilli in the sputum. In the absence of a positive sputum the prognosis for patients with cavitated progressive massive fibrosis is no vorse than for non-cavitated progressive massive fibrosis.6). Treatment is unsatisfactory but the sputum positive cases should be given anti-tuberculous drugs for the symptomatic benefit which they frequently confer. In sputum negative cases cavitation is of little clinical significance and such cases only require reassurance and possibly symptomatic treatment.7) . The nature and pathogenesis of coalworkers' pneumoconiosis are discussed. It is considered that simple pneumoconiosis is a pure coal dust effect. Progressive massive fibrosis occurs in lungs which already contain a certain amount of coal dust and is probably the result of some additional factor. There is evidence that this factor is tuberculous infection but the hypothesis remains unproven. Cavitation often occurs in massive fibrosis and it appears to be due to two basic processes, tuberculosis or ischaemic necrosis, acting alone or in combination.