Endosonographic evidence of persistence of Crohn's disease-associated fistulas after infliximab treatment, irrespective of clinical response

PURPOSE: Infliximab has been reported to improve fistulizing Crohn's disease. Moreover, prompt healing of mucosal ulcers has been described. Whether fistulas disappear or remainders of fistulas persist is unknown. This study documents fistulous tracts before and after infliximab therapy by means of hydrogen peroxide-enhanced endosonography METHODS: Eight patients with perianal, vaginal, or perineal fistulas were treated with a triplet of infliximab 5 mg/kg infusions. At baseline, and at Week 4 after the last infusion, fistulas were documented by local inspection, digital examination, and hydrogen peroxide-enhanced anal or vaginal endosonography. RESULTS: Patients with vaginal or perineal fistulas did not respond clinically to therapy, whereas patients with perianal fistulas improved considerably. However, in all patents remainders of fistulous tracts were demonstrated by endosonographic techniques. CONCLUSIONS: Short-term treatment of Crohn's disease-associated fistulas with infliximab does not induce disappearance of fistulous tracts, irrespective of therapeutic response.