Fistula dysfunction secondary to a subcutaneous myelomatous deposit.

Arteriovenous fistula dysfunction is a frequent complication in, and hindrance to, patients with end stage kidney disease undergoing renal replacement therapy with intermittent haemodialysis. We present an unusual complication in a 68-year-old male patient undergoing haemodialysis therapy for end stage kidney failure caused by biopsy-proven multiple myeloma. We explore the occurrence of an extramedullary cutaneous myeloma deposit situated adjacent to an arteriovenous fistula resulting in fistula dysfunction. This is the first reported case in the English literature of a myeloma deposit encasing an arteriovenous fistula, deriving its blood supply from the fistula and thus undergoing rapid growth, eventually leading to fistula dysfunction.