Azathioprine and 6-mercaptopurine for the treatment of perianal Crohn's disease in children

Numerous adult studies show a 30-65% response rate to azathioprine (AZA) or 6-mercaptopurine (6-MP) fur significant perianal Crohn's disease. The aim of this study was to evaluate whether these drugs healed pediatric perianal Crohn's disease. Records of pediatric Crohn's patients were retrospectivel y reviewed for significant perianal disease treated with AZA or 6-MP for gr eater than or equal to 6 months. The patient's perianal disease was reviewe d and evaluated for fistulas, drainage, induration, and tenderness. In addi tion, the patients were given a score using the Irvine Perianal Disease Act ivity Index (PDAI). Patients were retrospectively scored upon initiation of treatment and after six months of therapy. Possible scores ranged from 0-2 0. Twenty patients mel the study criteria. Five patients were considered tr eatment failures. One patient required a colostomy after 1.5 months of ther apy, one developed pancreatitis, and three were noncompliant with therapy. Of the remaining 15 patients who were treated for greater than or equal to 6 months, 67% had an improvement in drainage, 73% in tenderness, 60% in ind uration, and 40% in fistula. closure. The mean Irvine PDAI was 7.67 +/- 2.1 9 initially and 4.40 +/- 1.72 after six months of therapy. The improvement was statistically significant (p < 0.001). AZA and 6-MP are effective treat ments For healing significant perianal Crohn's disease in pediatrics.