[Ochronotic arthropathy: the value of bone scintigraphy in alkaptonuria]

We report the case of a 62 year old man diagnosed of alkaptonuria who was referred to our department to undergo bone scintigraphy for polyarthralgia. The patient had a history of pain in lumbar and thoracic spine, right shoulder and left knee. Bone scintigraphy showed multiple joint disease with increased uptake in both shoulders, knees and spine. Higher uptake stood out in painful right shoulder and left knee joints. Ochronotic arthropathy that is developed in alkaptonuric patients is a degenerative joint disease. X-ray studies in this patient showed marked degenerative arthrosis in knees and shoulders, without more intense involvement in the symptomatic joints. Lumbar spine X-rays showed intervertebral disk calcification with disk collapse and fusion of the vertebral bodies with relative sparing of sacroiliac joint, which is a classic feature of ochronotic arthropathy. This case highlights the utility of bone scintigraphy in the evaluation of joint involvement as well as its correlation with clinical course and potential usefulness in the follow-up of this disease.