Oral tacrolimus for steroid-dependent and steroid-resistant ulcerative colitis in children

To evaluate tacrolimus in 3 situations: for the induction of remission in children with severe steroid-resistant ulcerative colitis (UC); for steroid sparing in children with steroid-dependent UC in whom treatment with other immunosuppressants fails; and for the maintenance of remission in children with steroid-dependent and steroid-resistant UC.

We retrospectively evaluated 18 consecutive patients (13 with pancolitis) who were treated with oral tacrolimus at our institution from May 1999 to October 2005. Nine patients had steroid-resistant UC and 9 patients were steroid-dependent. We started patients initially on tacrolimus 0.2 mg/kg divided twice daily, with a goal plasma trough level of 10 to 15 ng/mL for the first 2 weeks, and then titrated doses to achieve plasma levels between 7 and 12 ng/mL after induction.

Of the 18 patients in this study, 17 showed a positive response to tacrolimus therapy (ie, cessation of diarrhea and other symptoms) and 5 showed a prolonged response to tacrolimus. The mean time from initiation of tacrolimus therapy until response was 8.5 days. The mean duration of response was 260 days. Eleven of 18 patients required colectomy, including all of the patients with steroid-resistant UC, but only 2 of 9 who were steroid-dependent. The mean time from initiation of tacrolimus until colectomy was 392 days.

It is possible that tacrolimus may benefit selected patients with steroid-dependent UC, including those who are intolerant of 6-mercaptopurine or azathioprine. Conversely, patients with steroid-resistant UC are unlikely to sustain a prolonged clinical response to tacrolimus and seem to require colectomy eventually. Careful considerations of risk versus benefit, as well as close monitoring for adverse effects, are essential in all patients.