Ulcerative colitis flair induced by mesalamine suppositories hypersensitivity.

Mesalamine suppositories have been used widely for the treatment of distal ulcerative colitis and considered to be safer than systemic administration for its limited systemic absorption. However, previous studies have shown that mesalamine suppository occasionally causes severe hypersensitivity reactions including fever, rashes, colitis exacerbation and acute eosinophilic pneumonia. Here we present a 25-year-old woman with ulcerative colitis with bloody diarrhea accompanied by abdominal pain and fever which were aggravated after introduction of mesalamine suppositories. In light of symptom exacerbation of ulcerative colitis, increased inflammatory injury of colon mucosa shown by colonoscopy and elevated peripheral eosinophil count after mesalamine suppositories administration, and the Naranjo algorithm score of 10, the possibility of hypersensitivity reaction to mesalamine suppositories should be considered, warning us to be aware of this potential reaction after administration of mesalamine formulations even if it is the suppositories.