Bone cysts and haemodialysis-related amyloidosis

Carpal tunnel syndrome and arthropathy are frequent complications of long-term haemodialysis. Both are associated with cystic lesions of bone and are related to synovioarticular deposition of a new type of amyloid derived from circulating beta 2-microglobulin. Retrospective analysis of the radiographic skeletal surveys of all 58 patients on haemodialysis for 6 or more years revealed one or more cystic bone lesions in 36% of patients. Radiographic analysis indicated that a number of these cysts were due to hyperparathyroid bone disease or joint degeneration, but a majority showed features suggesting an arthropathy of another aetiology. We present evidence that the development of these latter cysts in an individual on long-term dialysis is an indicator of the presence of synovioarticular amyloidosis of the beta 2-microglobulin type. The radiographic characteristics and development of these cysts, which we believe are due to bony infiltration from synovioarticular amyloid are described.