[Acute bilateral shoulder pain as initial presentation of ochronosis: a case report and literature review].

Ochronosis is a rare genetic metabolic disorder resulting from a constitutional lack of homogentisic acid oxidase and subsequent accumulation of its substrate causing destruction of connective tissues with various systemic abnormalities. Typical musculoskeletal symptoms are arthropathy and low back pain and stiffness. Arthropathy primarily affects knee and hip joints, but shoulders are less frequently involved. We describe a case of ochronosis initially presented as acute bilateral shoulder pain. Review of literature with respect to the etiology, natural course of the disease, differential diagnosis and management was made.