Foot gangrene associated with cholesterol crystal embolism in a maintenance hemodialysis patient

Abstract

A 62-year-old Japanese man with a one-year history of hemodialysis was transferred because of the development of foot gangrene. He was also complicated by cerebral infraction and abdominal aortic aneurysm. The patient complained of painful digital cyanosis and ulcer on the left foot. Computed tomographic angiography and magnetic resonance angiography demonstrated a completely occluded left femoral artery and right popliteal artery ; thus, he was diagnosed as having severe arteriosclerosis obliterans in the bilateral lower extremities, and this arteriosclerosis obliterans was thought to be the cause of foot gangrene. Below-the-knee amputation of the left lower limb was performed. However, cholesterol crystals were found in the small artery obtained from the ulcer on the amputated foot specimen, indicating cholesterol crystal embolism had also occurred and might have contributed to the development of foot symptoms. As systemic anticoagulation therapy, i.e., administration of heparin and low-molecular-weight heparin in hemodialysis, is one of the risk factors for the occurrence of cholesterol crystal embolism, we used nafamostat mesilate as hemodialysis-associated anticoagulation. This study suggests that physicians should consider cholesterol crystal embolism in the differential diagnosis for foot gangrene in maintenance hemodialysis patients.