A 78-year-old man with obstruction of the right common femoral artery due to arteriosclerosis obliterans underwent successful amputation of his leg. On the first postoperative day he received transfusion of three units of preserved blood. He continued to recover until postoperative day 7, when he developed a high fever, erythroderma and diarrhea. His condition gradually deteriorated and on postoperative day 15 he demonstrated severe and progressive leukopenia and thrombocytopenia. Although he underwent intensive treatment he died on postoperative day 20. A skin biopsy specimen revealed evidence of post-transfusion graft-versus-host disease.

Immune heparin-induced thrombocytopenia (HIT) is a crucial side effect of heparin therapy. We report the case of a 52-year-old man who was strongly suspected of having HIT after urgent descending aorta replacement. This case required continuous hemodiafiltration (CHDF) anticoagulated with unfractionated heparin (UFH) for acute renal failure after the operation. The patient developed thrombocytopenia and thrombus emphraxis in the circuit on the seventh day and was suspected of having HIT. UFH was ceased and replaced with argatroban. After then, thrombus emphraxis was not seen in the circuit and the platelet count was recovered promptly. He tested positive in an enzyme-linked immunosorbent assay for anti-platelet factor 4/heparin antibodies (anti-PF4/H Abs). Six months later, we found, an expanding thoracoabdominal aortic aneurysm and performed thoracoabdominal aorta replacement. We selected heparin anticoagulation for cardiopulmonary bypass because anti-PF4/H Abs were negative at that time. Thrombus emphraxis was not found during the operation. The patient developed neither thrombocytopenia nor thrombosis in the perioperative period.