Severe abdominal pain associated with allergic reaction to nafamostat mesilate in a chronic hemodialysis patient.

A 33-year-old woman was referred from an outside dialysis clinic to our hospital because of severe abdominal pain during hemodialysis. She had been on chronic hemodialysis for the past 11 years due to chronic glomerulonephritis. Nafamostat mesilate was used as an anticoagulant for hemodialysis, because it was during her menstrual period with hypermenorrhea. On admission, she had no abdominal pain or gynecological abnormalities. On the second day, she had similar abdominal pain during hemodialysis with nafamostat mesilate in our dialysis unit. The abdominal pain disappeared within 60 minutes after discontinuing the hemodialysis. We re-started dialysis using heparin instead of nafamostat mesilate and she had no symptoms. The titer of total immunoglobulin E was high. The drug lymphocyte stimulation test was positive for nafamostat mesilate and antigen specific immunoglobulin E to nafamostat mesilate was highly positive in her blood. Although an allergic reaction to nafamostat mesilate is a rare complication, it should be one of the differential diagnoses of abdominal pain occurring during hemodialysis.