THE PATHOLOGY OF EMPHYSEMA

The recognition of lung disease in coal workers: The role of Gough–Wentworth whole lung sections

From the identification of a specific lung disease caused by coal dust exposure in miners in 1831 until the demonstration of the association of that exposure to risk of emphysema in 1984, there was continuous argument about the harmfulness of coal dust. Ill health in miners was attributed variously to tuberculosis, quartz exposure or cigarette smoking. An acceptance that coal dust was harmful only started with investigative radiology and pathology in the 1920s, and physiology in the 1950s. Most of the early investigations were in South Wales, the centre of the most important coal field in Great Britain. Among the investigators was Professor Jethro Gough who, with his technician James Wentworth, introduced a technique for making thick sections of whole, inflated lungs on paper backing. Here, we describe this method and its central role in understanding the relationships between coal dust exposure, pneumoconiosis, emphysema and lung dysfunction in miners.

Serum angiotensin converting enzyme activity in patients with chronic renal failure on long term hemodialysis

Serum angiotensin converting enzyme activity was assayed by a spectrofluorometric method in 19 patients with chronic renal failure on long term hemodialysis and 19 control subjects. Converting enzyme activity was increased in 11 of 19 (58%) patients compared with the controls (p less than 0.005). There was no correlation between serum converting enzyme activity and plasma renin activity or blood pressure in the patients. Possible mechanisms responsible for the increased converting enzyme activity are discussed.

Radiological distribution of pulmonary emphysema. Clinical and physiological features of patients with emphysema of upper or lower zones of lungs

Martelli, N. A., Hutchison, D. C. S., and Barter, C. E. (1974).Thorax, 29, 81-89. Radiological distribution of pulmonary emphysema: clinical and physiological features of patients with emphysema of upper or lower zones of lungs. Pulmonary emphysema exists in two main pathological forms, centrilobular and panlobular (panacinar) emphysema, the lesions predominantly affecting the upper and lower zones of the lungs respectively. There is disagreement among authors as to the clinical and physiological differences between these two forms, and direct evidence of the pathological type is seldom available during life. Patients with emphysema can, however, be divided on radiological criteria into an `upper zone' and a `lower zone' group, and it can be argued that these groups relate respectively to the centrilobular and panlobular forms of the disease. The evidence is far from conclusive but it was thought that a comparison of the two radiological groups would be of value. Patients in whom there was no obvious zonal preponderance were not included in the study.

Fifty patients with definite radiological evidence of pulmonary emphysema have been studied, those with α₁-antitrypsin deficiency being excluded. Thirty-one patients (62%) had emphysema which predominantly affected the upper zones of the lungs; the lower zones were the more severely affected in the remainder. Bullae were found in approximately equal proportions in each group. All the patients were, or had been, cigarette smokers. There was no significant difference between the mean ages of the two groups; only seven patients were free from exertional dyspnoea, all being in the upper zone group. Chronic bronchitis occurred with equal frequency in the two groups but started on average about 10 years earlier in those with lower zone disease; the latter patients had rather more severe airflow obstruction and more severe blood-gas abnormalities. The presence or absence of chronic bronchitis per se, however, did not appear to have any significant effect upon the common respiratory function tests. No data emerged from this study which suggested that there were differing aetiological factors in the two groups.

Pulmonary changes and cor pulmonale in mucoviscidosis

The lungs of eight cases of cystic fibrosis in patients ranging from age 19 days to 23 years were examined by the large-section technique of Gough and Wentworth (Gough, 1960). All cases showed in life a susceptibility to staphylococcal and pseudomonal bronchopneumonia. In all cases the bronchial tree was plugged with mucus. The lungs from the older patients showed diffuse and pronounced bronchiectasis with luxuriant peribronchial granulation tissue and dilatation of the pulmonary arterial system. The distal air spaces in all cases showed only minimal distension and only in the eldest was there any evidence of destructive emphysema. Three cases developed cor pulmonale which we thought was the result of hypoxaemia due to a ventilation-perfusion imbalance.

Environmental factors in emphysema and a model system with NO.2

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