Serum vitamins and inflammatory bowel disease in children: a case-control study

Background Micronutrient deficiencies are common in pediatric inflammatory bowel disease (IBD), yet data on multiple vitamin profiles remain limited. This study aimed to comprehensively evaluate serum vitamin levels in children with IBD and explore their associations with immune cell profiles. Methods A retrospective observational study was conducted at the Children’s Hospital Affiliated to Zhengzhou University. A total of 46 children diagnosed with IBD who had vitamin profiling were enrolled between March 2022 and March 2026. A control group of 46 healthy children, who underwent health check-ups and vitamin assessments during the same period, were also included, matched 1:1 for age and sex. Clinical and laboratory data were retrieved from the hospital’s electronic medical record system. Serum levels of vitamins A, D, E, K, B1, B2, B3, B5, 5-methyltetrahydrofolate, and C were measured using ultra-high performance liquid chromatography–tandem mass spectrometry. Results Compared with controls, IBD patients had significantly lower vitamin A (VA) and vitamin C (VC) levels, while vitamin E (VE) levels were higher (all P < 0.05). Deficiency rates of VA (76.1% vs. 28.3%), VC (50.0% vs. 26.1%), and vitamin D (41.3% vs. 21.7%) were significantly increased in the IBD group (all P < 0.05). Within the IBD cohort, VA, VD, and VC levels correlated significantly with neutrophil and lymphocyte percentages. Multivariate logistic regression identified lower VA level (OR = 0.159, 95% CI: 0.032-0.792, P = 0.025) and VA deficiency (OR = 7.800, 95% CI: 1.735–35.055, P = 0.007) as factors independently associated with IBD. Conclusions Pediatric IBD patients exhibit significant deficiencies in VA, VC, and VD, and within the IBD cohort, these vitamins (VA, VD, and VC) correlate significantly with neutrophil and lymphocyte percentages. Multivariate regression suggests a potential independent association between VA status and pediatric IBD, though these are preliminary observational findings. This study provides preliminary multi-vitamin profiling data for pediatric IBD, highlighting the need for attention to VA and VC deficiencies alongside routine VD monitoring. Further validation in larger multicenter cohorts is required.