Caplan syndrome, also known as rheumatoid pneumoconiosis, is the combination of seropositive rheumatoid arthritis and a characteristic pattern of fibrosis.
Affects 2-6% of patients with pneumoconiosis (in Wales) 4 and is caused by disintegrating macrophages leaving a necrotic core with a surrounding pigmented (black) dust ring and fibroblasts 4-5.
- 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
First described by A Caplan in 1953 1.
- 1. Caplan A. Certain unusual radiological appearances in the chest of coal-miners suffering from rheumatoid arthritis. Thorax. 1953;8 (1): 29-37. Thorax (link) - Free text at pubmed - Pubmed citation
- 2. Honma, Koichi; Vallyathan, Val. Annals of Occupational Hygiene. doi:10.1093/annhyg/46.suppl_1.265
- 3. Fauci AS, Braunwald E, Kasper DL et-al. Harrison's principles of internal medicine. McGraw-Hill Professional. ISBN:0071466339. Read it at Google Books - Find it at Amazon
- 4. Dähnert W. Radiology review manual. Lippincott Williams & Wilkins. (2003) ISBN:0781738954. Read it at Google Books - Find it at Amazon
- 5. Grainger RG, Allison DJ. Grainger and Allison's diagnostic radiology, a textbook of medical imaging. Churchill Livingstone. (2001) ISBN:0443064326. Read it at Google Books - Find it at Amazon