Rheumatoid Pneumoconiosis in Association with Asbestosis.

In 1953 a new syndrome was described in which the association of rheumatoid arthritis with nodular fibrosis of the lung parenchyma was noted (Caplan, 1953). Though this condition resembles progressive massive fibrosis in some ways, there are certain distinctive features. The opacities that are found in Caplan's syndrome are usually more peripherally situated, tend to be multiple, and more commonly affect both lungs. The unusual radiological features that lead to the recognition of the syndrome were originally observed in a group of coal-miners with rheumatoid arthritis, though since then the syndrome has been described in other pneumoconioses, including asbestosis (Rickards and Barrett, 1958 ; Tellesson, 1961 ; Campbell, 1958). Furthermore, it is now realized that occasionally the parenchymal nodules may precede the development of arthritis by several years. This case report has several unusual and interesting features: first, detailed pulmonary function studies and a lung biopsy were performed; secondly, the subject had no overt evidence of rheumatoid arthritis; and lastly, the biopsy revealed the presence of asbestosis, an occupational hazard not to be expected in a man who had been an arc-welder all his life.