5-Aminosalicylic acid enemas in refractory distal ulcerative colitis: a randomized, controlled trial.

5-Aminosalicylic acid (5-ASA), the presumed active moiety of sulfasalazine, has shown clinical efficacy when administered per rectum as initial therapy to patients with distal ulcerative colitis. We report the results of a randomized double-blind trial comparing nightly retention of a 4-g 5-ASA enema with continued administration of hydrocortisone enemas in 18 patients with persistent active distal ulcerative colitis after at least a 3-wk course of treatment with 100-mg hydrocortisone enemas with or without oral sulfasalazine. Continuation of hydrocortisone enemas rather than placebo was used in the control group to reflect the realistic alternative therapy likely to be employed in current practice. Response to therapy was assessed after 3 wk by comparing pretreatment and posttreatment point scores of clinical, sigmoidoscopic, and histological severity. Improvement in clinical score was achieved in seven of nine 5-ASA enema-treated patients versus one of nine hydrocortisone enema-treated patients (p less than 0.05). Sigmoidoscopic and histological improvement generally paralleled clinical improvement. We conclude that in patients with distal ulcerative colitis unresponsive to standard therapy, treatment with 5-ASA enemas results in significant short-term clinical and sigmoidoscopic improvement in a majority of cases. Moreover, a significantly greater number of refractory patients improve when switched to 5-ASA enemas than when continued on standard therapy.