RESUMO
Over the past year epidemiological, immunopathological and morbid anatomical studies have been in progress in an attempt to define the aetiology of an obscure form of diffues pulmonary fibrosis in Guyana. Dr. H. M. S. G. Beadnell of Lusignan hospital has kept a record of all cases of pulmonary fibrosis referred to him. 14 of these patients were interviewed and examined. All were Indian aged 49-75 years, and 9 were women. The onset had been insidious, there being progressive dyspnoea, dry cough and weight loss. Common findings were central cyanosis, basal crepitations and signs of right ventricular hypertropy. Chest X-ray showed diffuse fibrotic changes and areas of consolidation. Lung function showed severe obstructive airways disease in most, and restrictive lung disease in a few. Patients were questioned about previous occupations, dust exposure and smoking habits. This revealed that all smoked blackfat tobacco smoking was determined during a population survey of two local communities. Only eleven blackfat tobacco smokers were found, all Indian women, and three of these had typical pulmonary fibrosis. 16 people known to smoke blackfat tobacco were examined; 12 had evidence of respiratory disease and 5 had radiographic appearances of pulmonary fibrosis. Further epidemiological studies undertaken more recently lend support to these findings(AU)