Abstract
A 69-year-old man suffered from sudden, severe back pain and was transported to our emergency room. An emergency Y-graft replacement was performed due to the rupture of an abdominal aortic aneurysm. We found a major thrombus in his right internal jugular vein by a CT scan performed on day 9, so we started the continuous intravenous infusion of heparin as thrombolytic therapy. On the same day, a hemodiafiltration circuit was frequently occluded by blood clots. The next day, the platelet count decreased to 40% compared with that the day before. We considered the possibility of heparin-induced thrombocytopenia (HIT) and immediately stopped administering heparin. On day 11, HIT antibodies with a high titer were detected. Then, we continuously administered argatroban. However, we had no choice but to decrease its dosage and finally stopped its administration after five days because of a prolonged APTT. The patient developed multiple organ dysfunction syndrome and died on day 59. We think that this case could have involved HIT accompanied by consumptive coagulopathy. The administration of argatroban is the only approved treatment for HIT in Japan. The dosage of argatroban has to be set according to the APTT. When a patient suffers a tendency for bleeding or a prolonged APTT, there is no choice but to reduce its dosage or stop its administration. There is no established therapy for HIT-associated consumptive coagulopathy.
