Tacrolimus Exerts Only a Transient Effectiveness in Refractory Pediatric Crohn Disease: A Case Series.

OBJECTIVES: Tacrolimus is an immunosuppressive agent that has been proposed in the treatment of severe ulcerative colitis. The present study examined the effectiveness and safety of tacrolimus in treating refractory Crohn disease (CD) colitis in children. METHODS: All children treated by oral tacrolimus for CD colitis at a tertiary pediatric center were included in the study. All patients were refractory to steroids and infliximab. Clinical response (decreased pediatric CD activity index [PCDAI] >15 and PCDAI <30) and remission (PCDAI <10) were monitored at 2, 4, 6, 12, and 24 months after induction. Tacrolimus blood levels and adverse effects were also noted. RESULTS: Among 220 patients with CD, 8 children (including 3 girls, median age 14 [9.5-18] years) were registered with a median PCDAI of 58.7 (32.5-65) before tacrolimus initiation. In patients treated with tacrolimus, the overall clinical response rates were 6/8, 3/8, 2/8, 2/8, and 1/8 with a remission rate of 4/8, 0/8, 0/8, 2/8, and 0/8 at 2, 4, 6, 12, and 24 months, respectively. At 2 months, the PCDAI scores were lower than those at induction (median 11.2; P = 0.004) with the mean whole plasma level of tacrolimus being 8.75 ng/mL (5.9-10 ng/mL). Adverse events occurred in 6 of 8 patients, including renal dysfunction, insulin-dependent diabetes, paresthesia, and tremor. Tacrolimus interruption was required in 2 cases. CONCLUSIONS: Tacrolimus could be considered to transiently treat refractory CD colitis. Tacrolimus could be used as a "bridge" toward another medical option in pediatric CD, although its adverse events are frequent.