Acute ulcerative colitis--a rare complication of sulfasalazine therapy.

A 43-year-old female suffering from ulcerative colitis did not improve under therapy with sulfasalazine. Following withdrawal of sulfasalazine and its replacement by systemic steroids and metronidazole++ she went into clinical and endoscopic remission. A second trial with sulfasalazine was, again, followed by a rapid and sever relapse of the colitis. On discontinuation of sulfasalazine therapy, gross inflammation resolved immediately. This adverse reaction to sulfasalazine has been reported previously in only four cases. The pathophysiology of this event is unknown.