Background: Treatment with sulphasalazine of patients with mild and moderate forms of Crohn's disease may result in side effects in some of them.
Case report: An 11-year-old girl with Crohn's disease was given 40 mg/kd/day of sulphasalazine after achieving remission with prednisone. She developed urticaria and eosionophilia 8 days later, then extended skin edema during a second course of sulphasalazine requiring methyl prednisolone therapy. Mesalazine administration (25 mg/kg/day), one month later, resulted to watery stools, vomiting, and fever, a side effect observed again after two further mesalazine challenges of one-month interval. Eosionophilia was present and the lymphocyte stimulation test with mesalazine was positive. Successful desensitization to sulphasalazine could be obtained 9 months later permitting further safe administration of this drug up to 18 months.
Conclusion: Hypersensitivity to sulphasalazine may be successfully overcame by oral desensitization, especially in those patients with low-grade activity of Crohn's disease.