Idiopathic progressive pulmonary fibrosis.

Five patients with progressive fibrotic lung disease are described. The dominant symptom was slowly increasing dyspnoea, and cough and sputum were not prominent. Marked weight loss was also a feature. There was severe restrictive impairment of ventilation with normal arterial gas tensions. The changes were confined to the upper parts of the lung in some but others had more generalized disease. The duration has varied so far from two to 17 years. The lung changes are considered to be due to dense progressive fibrosis. Necropsy in two confirmed this. Histologically there was monotonous fibrosis with lymphoid collections and secondary bronchiectasis, a picture similar to that found in association with ankylosing spondylitis. None of these patients had joint disease. Tuberculosis was excluded as a cause by exhaustive bacteriological tests and the failure of chemotherapy to stop deterioration. All other recognized types of infective and non-infective progressive lung fibrosis were also excluded, and this is not considered to be a variant of cryptogenic fibrosing alveolitis. Though these patients have many features in common they do not necessarily have the same pathogenesis. They are presented as an encouragement to further study.