Two cases developing HIT during maintenance hemodialysis therapy

Is HIT antibody a risk factor for blood coagulation in dialysis patients?

Abstract

We experienced 2 patients who developed heparin-induced thrombocytopenia (HIT) a few years after the initiation of hemodialysis therapy. Both patients demonstrated anti-PF 4/heparin complex antibody (HIT antibody) prior to symptomatic onset. Case 1, a 68-year-old woman. She had been treated chronic kidney disease by dialysis using heparin as an anticoagulant since 2001. We initially detected HIT antibody in her blood in April 2002. In August 2002, she developed HIT with blood coagulation in the circuit using heparin. Thereafter, we changed anticoagulant to nafamostat mesilate. HIT antibody remains positive in this patient. Case 2, a 71-year-old man. He had been treated chronic kidney disease on dialysis using heparin as anticoagulant since 1996. He had shown episodes of vascular access clotting between 2000 and 2004. HIT antibody was detected in his blood in April 2002. After the last episode of vascular clotting on 2004, he developed HIT with blood coagulation in the circuit using heparin. Thereafter, we changed argatroban as an anticoagulant. HIT antibody remains positive in this patient. We measured HIT antibodies for 129 dialysis patients in our clinic in 2002. As a result, 5 (3.9%) patients was found to have HIT antibody. We must carefully monitor the cases with HIT antibody, even if the patients do not initially show any signs of HIT. It is likely that HIT may develop during afuture dialysis session.