A national survey of bird fanciers' lung: including its possible association with jejunal villous atrophy. (A report to the Research Committee of the British Thoracic Society).

In 143 British patients with bird fanciers' lung (BFL), jejunal biopsy was requested in 25 because symptoms and investigations suggested malabsorption. Fourteen biopsies were performed; jejunal villous atrophy was found in five and increased lymphocytes in jejunal mucosa in two others. Budgerigars and pigeons were the birds most frequently implicated in causing respiratory symptoms. Fever was recorded more often in pigeon fanciers. Twenty-one of 47 patients with budgerigar fanciers' lung were females aged over 65, whereas 29 of 47 patients with pigeon fanciers' lung were males aged under 45 years. Of all patients with BFL, 61% were life-long non-smokers and only 15% smokers, compared with the national average of 40% smokers. Bilateral generalized small radiographic opacities and a restrictive ventilatory defect characterized the disorder. These tended to improve after avian withdrawal only in patients under 45 years of age whose symptoms had been present for less than 2 years. Avian species was not related to the severity of the disorder or to subsequent recovery. Serum precipitins were inconsistent and of no prognostic value.