Fistula Calprotectin as a Biomarker of Local Inflammation and Treatment Response in Perianal Fistulizing Crohn's Disease

作者：Runqi Wang, Yanglong Wu, Dongbo Xu, Yeyi Yang, Keyu Qian, Jia Kuang, X Wang, Chaoyi Lin, Xia Liu, Guangyu Wu, Dan‐dan Ruan, Binghua Chen, Ye Zhang, Yousheng li, Yousheng li, Zi Wang, Zhe Cui, Dongxing Cao · 发表于：Alimentary Pharmacology & Therapeutics · 年份：2026 · DOI：10.1111/apt.70600 · 被引用次数：2 · 研究领域：Anorectal Disease Treatments and Outcomes、Inflammatory Bowel Disease、Hidradenitis Suppurativa and Treatments

BACKGROUND: Accurate assessment of tract-specific inflammatory activity remains difficult in perianal fistulizing Crohn's disease (pfCD), as current clinical and imaging indices incompletely reflect local activity. AIMS: To evaluate fistula calprotectin (FiCP) as a tract-specific biomarker, focusing on diagnostic accuracy, associations with histological, clinical, and radiological indices, longitudinal responsiveness, and local infliximab exposure. METHODS: In this single-center observational study (April 2023-July 2025; n = 105), patients with pfCD provided fistula exudate samples during surgical or outpatient assessment. FiCP concentrations were quantified by ELISA and correlated with histological inflammation, the Perianal Disease Activity Index (PDAI), the MRI-based modified Van Assche Index (mVAI), and total fistula volume (TFV). Diagnostic performance was analysed using receiver operating characteristic (ROC) curves with DeLong comparison, and treatment responsiveness was evaluated longitudinally using the standardised response mean (SRM). Serum and local infliximab concentrations were measured using ELISA. RESULTS: FiCP levels were significantly higher in fistulas with severe versus mild histological inflammation (p = 0.021) and in clinically or radiologically active tracts (both p < 0.001). FiCP correlated with PDAI (R = 0.61), mVAI (R = 0.40), and local infliximab concentration (R = -0.64). FiCP discriminated active from quiescent fistulas (AUC 0.843; 95% CI 0.758-0....