title: Arthritis due to synovial involvement by extramedullary haematopoiesis in myelofibrosis with myeloid metaplasia.
abstract: A 60-year-old man presented with polyarthralgias, a psoriasiform rash, and severe elbow pain. Peripheral blood smear and bone marrow biopsy established a diagnosis of myelofibrosis with myeloid metaplasia. Biopsy of the skin lesions revealed a nonspecific dermatitis. The clinical presentation was inconsistent with psoriatic arthritis, and there was no evidence for associated gout or collagen-vascular disease. Histological examination of tissue taken at the time of synovectomy indicated elbow arthritis to be due to myeloid metaplasia involving the synovial membrane.
mesh_terms: D001168:Arthritis / Q000209:etiology* / Q000473:pathology; D006410:Hematopoiesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D055728:Primary Myelofibrosis / Q000150:complications*; D013583:Synovial Membrane / Q000473:pathology*