To evaluate the long-term effectiveness of sphincter-preserving seton surgery combined with Adalimumab (ADA) in pediatric patients with perianal fistulizing Crohn’s disease (PFCD), and to explore predictive factors affecting efficacy.

A retrospective analysis was conducted on the clinical data of pediatric patients who met the inclusion and exclusion criteria between January 1, 2021 and December 31, 2024, to healing rate of anal fistula and the clinical remission rate. Binary logistic regression analysis was used to identify factors affecting fistula healing, and a receiver operating characteristic (ROC) curve was plotted for predictive indicators.

Seventy-one patients were included. The median follow-up time was 115 (100, 127) weeks. At the follow-up endpoint, 32/71 (45.1%) patients achieved healing of anal fistulas, and 39.4% (28/71) achieved fistula healing under MRI, and 39/71 (54.9%) patients achieved clinical remission. Univariate logistic regression results indicated that Body Mass Index (BMI) (OR: 0.851, 95%CI: 0.725~0.999, P=0.049) was a protective factor associated with fistula healing, while PCDAI (OR: 1.347, 95%CI: 1.168~1.554, P＜0.001), SES-CD (OR: 3.460, 95%CI: 1.839~6.509, P＜0.001) and fistula complexity (OR: 21.562, 95%CI: 4.499~103.346, P＜0.001) were risk factors for poor fistula healing. Multivariate logistic regression showed that PCDAI was an independent risk factor affecting fistula healing in pediatric patients with PFCD (OR: 1.309, 95%CI: 1.087~1.576, P=0.005). The ROC curve constructed based on PCDAI demonstrated good predictive performance (AUC=0.907, 95%CI: 0.832~0.981, sensitivity 0.769, specificity 0.969, positive predictive value 0.968, negative predictive value 0.775, Youden index 0.738).

Sphincter-preserving seton surgery combined with Adalimumab is effective for treating PFCD. Baseline PCDAI has high accuracy in predicting perianal fistula healing outcomes in pediatric PFCD, which can assist clinical decision-making.