Surgical Treatment of Ischial Ulcers Associated with Deposition of β2-Microglobulin in Two Cases of Dialysis-related Amyloidosis

The accumulation of β2-microglobulin due to long-term hemodialysis is known as dialysis-related amyloidosis, a rare phenomenon that manifests as a subcutaneous mass. Subcutaneous β2-microglobulin amyloidomas are predominantly located on the buttocks. Owing to the load-bearing properties of this location and proximity to the anus, amyloidomas on the buttocks may be prone to pressure ulcers and infection. This report presents two cases of long-term hemodialysis patients who required surgical treatment for infected ulcers caused by buttock amyloidomas. In the first case, treatment failed after the amyloidoma was excised and covered with a single-stage skin flap. In the second case, successful treatment was accomplished by reducing the volume of the amyloidoma, followed by a pause to allow for granulation growth and a two-stage skin graft. Amyloids of this nature are known to be cytotoxic; thus, a robust wound preparation technique should be used until the excision site is fully covered with granulation tissue before wound closure is initiated at the time of surgery. In addition, buttock amyloidomas often extend subcutaneously through the hip joint, and repeated infections may lead to more severe outcomes, such as hip joint infections. The number of dialysis-related amyloidosis patients has been increasing in recent years; thus, we report these case studies to improve patient outcomes in similar cases.