[Caplan's syndrome in marble workers as occupational disease].

Rheumatoid pneumoconiosis is an uncommon combination of occupational lung disease caused by exposure to harmful silica dust with rheumatoid inflammation of the joints, rheumatoid arthritis, with an autoimmune background. Until now, the disease was observed mostly among coal and gold miners and granite workers. Written documents on the theme are summarized. This case study outlines the syndrome pathology with typical features presented by the worker, employed for many years in the marble industry. Although in general marble is free of silica, the collection of occupational anamnesis and familiarity with the patient's work conditions and demands gave the authors an opportunity to uncover the exposure source and to determine the most probable diagnosis.

Rheumatoid pneumoconiosis (Caplan's syndrome).

In 1953, Caplan described a characteristic radiographic pattern in coal miners with rheumatoid arthritis (RA) that was distinct from the typical progressive massive fibrosis pattern of coalworkers' pneumoconiosis. It consists of multiple well-defined rounded nodules on chest X-ray, from about 0.5 to about several centimetres in diameter, distributed throughout the lungs but predominantly at the lung periphery. Lesions appear often in crops, may coalesce and form a larger confluent nodule. Nodules often cavitate or calcify. They typically occur in the setting of pre-existing mild pneumoconiosis, but pneumoconiosis is not a prerequisite. The onset of the nodules is typically sudden, and their course varies thereafter, ranging from regression to progression. Histologically, the nodules have a characteristic appearance and are distinguishable from silicotic nodules or progressive massive fibrosis. Individual susceptibility is considered to play a role in the development of the disease. However, the pathogenetic link between exposure to silica, pneumoconiosis and RA has not been clarified conclusively. This review summarizes history, definition and current knowledge on epidemiology, pathology, pathophysiology, clinical presentation and treatment of Caplan's syndrome.