[Clinical characteristics and prognosis of children with perianal fistulizing Crohn's disease].

Objectives: To investigate the clinical characteristics, treatment, and prognosis of children with perianal fistulizing Crohn's disease (pfCD).

Methods: A retrospective analysis was conducted on the children, aged 6-17 years, who were diagnosed with Crohn's disease (CD) from April 2015 to April 2023. According to the presence or absence of perianal fistulizing lesions, they were divided into two groups: pfCD (=60) and non-pfCD (=82). The two groups were compared in terms of clinical characteristics, treatment, and prognosis.

Results: The incidence of pfCD was 42.3% (60/142). The proportion of males in the pfCD group was higher than that in the non-pfCD group. Compared with the non-pfCD group, the pfCD group had a significantly higher proportion of children with involvement of the colon and small intestine or those with upper gastrointestinal lesions (<0.05). Compared with the non-pfCD group, the pfCD group had a significantly higher rate of use of infliximab during both induction and maintenance treatment (<0.05). In the pfCD group, the children with complex anal fistula accounted for 62% (37/60), among whom the children receiving non-cutting suspended line drainage accounted for 62% (23/37), which was significantly higher than the proportion among the children with simple anal fistula patients (4%, 1/23) (<0.05). There were no significant differences between the two groups in mucosal healing rate and clinical remission rate at week 54 of treatment (>0.05). The pfCD group achieved a fistula healing rate of 57% (34/60) at week 54, and the children with simple anal fistula had a significantly higher rate than those with complex anal fistula (<0.05).

Conclusions: There is a high incidence rate of pfCD in children with CD, and among the children with pfCD, there is a high proportion of children with the use of biological agents. There is a high proportion of children receiving non-cutting suspended line drainage among the children with complex anal fistula. The occurrence of pfCD should be closely monitored during the follow-up in children with CD.