Caplan syndrome

Caplan syndrome, also known as rheumatoid pneumoconiosis, is the combination of seropositive rheumatoid arthritis and a characteristic pattern of fibrosis.

Although first described in coal miners (coal workers' pneumoconiosis), it has subsequently been found in patients with a variety of pneumoconioses .

Epidemiology

Affects 2-6% of patients with pneumoconiosis (in Wales) and is caused by disintegrating macrophages leaving a necrotic core with a surrounding pigmented (black) dust ring and fibroblasts .

Radiographic features

  • 5-50 mm well-defined nodules in the upper lung lobes/lung periphery
  • nodules may remain unchanged, multiply, calcify, or become thick walled cavities
  • background changes of pneumoconiosis
  • may have an accompanying pleural effusion
  • features often grow in short bursts

History and etymology

It was first described by A Caplan in 1953 .