Detection of specific IgE antibodies to nafamostat mesilate as an indication of possible adverse effects of leukocytapheresis using nafamostat mesilate as anticoagulant.

: The aim was to determine whether adverse effects of leukocytapheresis (LCAP) are related to nafamostat mesilate (NM) as an anticoagulant. Anti-NM IgE were detected in inflammatory bowel disease (IBD) patients who were administrated LCAP in our institute. Forty-nine patients (ulcerative colitis (UC)/Crohn's disease (CD): 30/19) were evaluated. Anti-NM IgE was measured by the ELISA method. Total IgE level and eosinophil count was tested concurrently. We retrospectively checked the presence of allergic symptoms and medications used concurrently with LCAP. Anti-NM IgE were present in six symptomatic patients (6/49; 12.2%) whose adverse effects were highly suspected to be from NM. However, 21 patients showed anti NM IgE-negative, in spite of the fact that their adverse effects were also highly suspected to be from NM. Through the detection of anti-NM IgE alone we could not estimate the relevance of NM  as  an  anticoagulant  to  the  adverse  effects  of  LCAP.