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What is Caplan's syndrome is pneumoconiosis with and explain in detail?
Pulmonary manifestations of RA include pleurisy with or without effusion, ILD in up to 20% of cases, necrobiotic nodules (nonpneumoconiotic intrapulmonary rheumatoid nodules) with or without cavities, Caplan syndrome (rheumatoid pneumoconiosis), pulmonary hypeension secondary to rheumatoid pulmonary vasculitis, organized pneumonia, and upper airway obstruction due to cricoarytenoid ahritis. Ref Harrison 19th edition pg 1713