Olecranon bursitis related to calcium pyrophosphate dihydrate crystal deposition disease. Clinical and pathologic study

A case of olecranon bursitis in an 81-year-old patient is presented. Analysis of the bursal fluid revealed positive birefringent crystals; radiographs showed calcifications in the distal triceps tendon. A bursectomy was performed. X-ray diffraction analyses demonstrated calcium pyrophosphate dihydrate patterns in a subcutaneous "tophus" and in a specimen of the tendon. On histologic examination, there was a bursitis with positive birefringent crystals on the bursa's inner surface; histologic images of "chondrocalcinosis" were observed in and around the tendon. It is concluded that bursitis may be part of the extraarticular manifestations of calcium pyrophosphate dihydrate crystal deposition disease.