S56 Utility of Red Cell Distribution Width in Assessing Ulcerative Colitis Activity and Its Correlation With Inflammatory Biomarkers

Background: Ulcerative colitis (UC) causes chronic inflammation of the colon and rectum, significantly affecting patients’ quality of life due to its variable symptoms. Effective management of UC requires an accurate assessment of inflammatory activity through biomarkers such as fecal calprotectin (FC), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). Red cell distribution width (RDW) is a laboratory parameter derived from a complete blood count that measures the variability in red blood cell size. An elevated RDW value may indicate the presence of inflammatory processes and oxidative stress. This parameter is readily available and can provide important prognostic information in patients with multiple inflammatory and chronic conditions. The objective of this study is to evaluate the utility of RDW in assessing UC activity and its correlation with other biochemical markers (ESR, CRP, FC). Methods: A cross-sectional, analytical relational study was conducted, including 94 patients with UC treated at the Inflammatory Bowel Disease Clinic at the General Hospital of Mexico “Dr. Eduardo Liceaga.” Patient data were collected, including demographic and clinical variables (disease extent, age at diagnosis, extraintestinal manifestations, and treatments received). UC activity was classified according to the New Yamamoto-Furusho Comprehensive Index for UC assessment (NYFCI), which includes clinical, biochemical, endoscopic, and histological parameters, categorizing patients as inactive or with mild, moderate, or severe activity. RDW, FC, CRP, and ESR levels were evaluated. Descriptive and comparative analyses were performed, as well as a correlation analysis of variables based on their distribution, using the corresponding statistical tests. Data analysis was conducted using the SPSS statistical package version 29. Results: Of the patients included in the study, 53.2% were women. The average age of the patients was 41.7 years (± 12.8), and the average age at diagnosis was 32 years (± 12.52). The majority of patients (62.8%) were classified as E3 according to the Montreal classification. CUCI activity, measured by the NYFCI, showed that 57.4% of the patients had moderate activity. The median biomarker values were: ESR of 11 mm/h (interquartile range 4-19.2), CRP of 4.1 mg/L (interquartile range 1.1-12.6), FC of 258 µg/g (interquartile range 69.1-800), and RDW of 15.9 (± 4.2). The comparative analysis showed significant differences between RDW values and disease activity level according to the NYFCI (p=0.04). Additionally, a positive correlation was found between RDW values and the NYFCI score (r=0.25; p=0.1), CRP (r=0.32; p=0.001), ESR (r=0.53; P< 0.001), and FC (r=0.23; p=0.2). No significant associations or correlations were found between RDW and gender, age, age at diagnosis, disease extent, presence of extraintestinal manifestations, or the type of treatment received by UC patients. Conclusions: Our study demonstrates that RDW could be a useful biomarker for assessing UC activity. A significant correlation was found between RDW values and other inflammatory biomarkers such as FC, ESR, and CRP. This parameter is easily accessible and can provide important prognostic information, thus improving the clinical management of UC patients.