Imaging findings of Copa syndrome in a 12-year-old boy.

Copa syndrome is a newly described autosomal dominant autoinflammatory disease that presents as pulmonary hemosiderosis and polyarticular arthritis. Twenty-one cases from five families have been reported to date. We present chest computed tomography (CT) and temporomandibular joint magnetic resonance (MR) findings of a 12-year-old boy presenting with dyspnea on exertion, fatigue and clubbing. Additional findings included a restrictive pattern of pulmonary involvement and positive inflammatory markers and autoantibodies. Genetic testing revealed a p.W240R variant of the COPA gene confirming the diagnosis of Copa syndrome. CT of the chest showed a nonspecific interstitial pneumonia pattern distributed mainly in the lower lobes. MR of the temporomandibular joints and follow-up CT three years later are also described.