Pediatric inflammatory bowel diseases in patients with genetic syndromes: A case–control multicentre SIGENP study

OBJECTIVES: To characterize the clinical phenotype and long-term outcomes of pediatric inflammatory bowel disease (IBD) in patients with genetic syndromes. METHODS: Multicenter observational case-control study using data from the Italian Society of Pediatric Gastroenterology, Hepatology, and Nutrition IBD registry. Patients diagnosed with pediatric-onset IBD (<18 years) between 2009 and 2024 were included. Syndromic cases were matched 1:2 with non-syndromic controls by gender, age at diagnosis, IBD type, and follow-up duration. Demographic, clinical, and therapeutic data were analyzed. RESULTS: Sixty-nine patients were included (23 syndromic and 46 controls). At diagnosis, syndromic patients had lower weight (-1.16 z-score, p = 0.004) and height (-1.43 z-score, p < 0.001); these differences persisted at follow-up. Diagnostic delay was longer in syndromic patients (+6.5 months, p = 0.045). Abdominal pain was less frequent at presentation (p = 0.01). Syndromic patients had more hospitalizations (IBD-related incidence rate ratio [IRR] 1.23, p = 0.033; non-IBD IRR 1.65, p < 0.001), more comorbidities (odds ratio [OR] 18.2, p < 0.001), and greater use of non-IBD medications (OR 8.17, p = 0.004). The risk of additional autoimmune diseases was higher but not statistically significant. CONCLUSIONS: Pediatric IBD patients with genetic syndromes show impaired growth and delayed diagnosis, while intestinal disease activity and treatment exposure are comparable to non-syndromic peers. The higher burden of comorbidities and hospitalizations indicates greater healthcare complexity and diagnostic challenges; early recognition and coordinated multidisciplinary care are reasonable clinical considerations, but their impact on outcomes requires prospective evaluation.