Juan Zhou ¹ Binrong Chen ² Zhicheng Wang ² Li Liu ¹ Hongjuan Ouyang ¹ Yanhong Luo ¹ Wenting Zhang ¹ Chenxi Liu ¹ Meizheng Zhan ¹ Jiaqi Duan ¹ Canli Li ¹ Jiang Na ¹ Jieyu You ¹ Hongmei Zhao ^1*

• ¹ Department of Gastroenterology and Nutrition, The Affiliated Children’s Hospital of Xiangya School of Medicine, Central South University(Hunan children’s hospital), Changsha, China
• ² The School of Pediatrics, Hengyang Medical School, University of South China(Hunan Children's Hospital), Changsha, China

Background: Delayed diagnosis of inflammatory bowel disease (IBD) is common in the European continent and North America, with limited research in Asia. We aimed to investigate factors influencing delayed diagnosis of IBD in Chinese children and the impact of delayed diagnosis on growth. Methods: This was a retrospective study. Clinical data on children with IBD were collected through electronic medical records. The diagnostic interval includes the time from symptom to hospital admission and admission to diagnosis. Diagnostic delay was defined as the upper quartile of the time interval from the first symptom to the diagnosis of IBD. For effect on growth indicators, the length of follow-up was at least three months from diagnosis.Results: This study included 222 children with IBD, predominantly with Crohn's Disease (86.0%). About a quarter of children take more than 366 days for the diagnosis of IBD, which is associated with a long interval between the first symptom onset and hospital admission. Multivariate logistic regression models showed that fever was associated with a prolonged time interval from first symptom onset to admission and the odd ratio (OR) was 0.45 (95% CI: 0.22, 0.94). Age and bloody stools were associated with prolonged intervals from admission to diagnosis, with ORs of 0.84 (95% CI: 0.77, 0.92) and 0.36 (95% CI: 0.14, 0.94), respectively. Delayed diagnosis was associated with height at first admission and follow-up. Compared to children without a delayed diagnosis, those who had one had a 5.87-fold higher chance of growth retardation upon initial admission (95% CI: 1.59, 24.05). After 15.7 months of followup, this elevated risk remained (OR: 3.28, 95% CI: 1.00, 10.50).Delayed diagnosis is common in Chinese children with IBD and is associated with persistent height impairment.