Subcutaneous deposition of beta 2-microglobulin amyloid in a long-term haemodialysis patient.

Subcutaneous deposition of beta 2-microglobulin (beta 2-M) amyloid is an uncommon finding in uraemic patients on long-term haemodialysis. A 60-year-old female on haemodialysis for 16 years developed a subcutaneous haematoma 2 years prior to death. At necropsy the lesion contained numerous deposits of beta 2-M amyloid as well as evidence of old haemorrhage, fibrous repair, dystrophic calcification and calcium oxalate crystal deposition. Highly sulphated glycosaminoglycans were present in the amyloid deposits. beta 2-M amyloid deposits were also present in the hip joint, cervical and lumbar spine, and in small blood vessels of the heart, liver, and lung. The possible role of trauma and tissue glycosaminoglycans changes in the formation of subcutaneous amyloid tumours is discussed.