Serum Immune-Inflammation Index as an Indicator of Disease Activity in Egyptian Ulcerative Colitis Patients

Background. Ulcerative colitis (UC) is a chronic inflammatory disease characterized by relapsing episodes that require accurate evaluation of disease activity to guide therapeutic decisions. Although endoscopy remains the gold standard for assessing mucosal inflammation, its invasive nature limits frequent use. The serum immune-inflammation index (SII), derived from routine blood counts, has emerged as a potential non-invasive biomarker of systemic inflammation.

Aim: to evaluate the role of SII in assessing disease activity and severity in UC patients.

Materials and methods. This cross-sectional study included 80 adult UC patients attending Ain Shams University Hospitals. Clinical evaluation, laboratory testing (C-reactive protein, fecal calprotectin, and complete blood count), and colonoscopic assessment using the Mayo Endoscopic Subscore were performed on the same day. SII was calculated as (platelet count × neutrophil count) / lymphocyte count.

Results. Of the 80 patients, 25 (31.25 %) were in remission and 55 (68.75 %) had active disease. SII values were significantly higher in patients with active UC compared to those in remission (1357.97 ± 831.17 vs. 582.86 ± 188.88; p < 0.001). SII positively correlated with C-reactive protein and fecal calprotectin, and negatively with lymphocyte count. At a cutoff of > 838.76, SII discriminated active disease from remission with 70.91 % sensitivity, 96.00 % specificity, and 86.1 % accuracy. A cutoff of > 1148.67 distinguished moderate-to-severe from mild disease with 78.00 % accuracy.

Conclusion. The SII is a simple, cost-effective, and reliable non-invasive marker for assessing disease activity and severity in UC. Its incorporation into routine monitoring may reduce dependence on frequent endoscopic evaluation. 

1. Li P., Wu Y., Xiong W., Cao J., Chen M., Yuan Z., et al. Association between the immune-inflammation index and the severity and clinical outcomes of patients with inflammatory bowel disease: A systematic review and meta-analysis. BMC Gastroenterol. 2025;25(1):414. DOI: 10.1186/s12876-025-04033-4

2. Elgenidy A., Alomari O., Emad T., Kamal S., Al Ghanam I., Sherif A., et al. Systemic Immune-Inflammation Index: Unveiling the diagnostic potential in ulcerative colitis through a comprehensive systematic review and meta-analysis. Gastroenterol Endosc. 2025;3(1):22–31. DOI: 10.1016/j.gande.2024.10.003

3. Zhang M.H., Wang H., Wang H.G., Wen X., Yang X.Z. Effective immune-inflammation index for ulcerative colitis and activity assessments. World J Clin Cases. 2021;9(2):334–43. DOI: 10.12998/wjcc.v9.i2.334

4. Yan J., Deng F., Tan Y., Zhou B., Liu D. Systemic immuneinflammation index as a potential biomarker to monitor ulcerative colitis. Curr Med Res Opin. 2023;39(10):1321–8. DOI: 10.1080/03007995.2023.2257599

5. Lin H., Bai Z., Wu Q., Chu G., Zhang Y., Guo X., et al. Inflammatory indexes for assessing the severity and disease progression of ulcerative colitis: A single-center retrospective study. Front Public Health. 2022;10:851295. DOI: 10.3389/fpubh.2022.851295

6. Xie Y., Zhuang T., Ping Y., Zhang Y., Wang X., Yu P., et al. Elevated systemic immune inflammation index level is associated with disease activity in ulcerative colitis patients. Clin Chim Acta. 2021;517:122–6. DOI: 10.1016/j.cca.2021.02.016

7. Mohammad Sadek A., Yousef Salim A., Afify A., Ibrahim N., Salem S. Diagnostic accuracy of low-cost blood test inflammatory markers in severe ulcerative colitis. Za- gazig University Medical Journal. 2024;30(7):3211–26. DOI: 10.21608/zumj.2024.311594.3517

8. Pakoz Z.B., Ustaoglu M., Vatansever S., Yuksel E.S., Topal F. Serum Immune-Inflammation Index assessment in the patients with ulcerative colitis. Gastroenterol Res Pract. 2022;2022:9987214. DOI: 10.1155/2022/9987214

9. Poenariu I.S., Boldeanu L., Ungureanu B.S., Caragea D.C., Cristea O.M., Pădureanu V., et al. Interrelation of hypoxia-inducible factor-1 alpha (HIF-1 α) and the ratio between the mean corpuscular volume/lymphocytes (MCVL) and the cumulative inflammatory index (IIC) in ulcerative colitis. Biomedicines. 2023;11(12):3137. DOI: 10.3390/biomedicines11123137

10. Schroeder K.W., Tremaine W.J., Ilstrup D.M. Coated oral 5-aminosalicylic acid therapy for mildly to moderately active ulcerative colitis. A randomized study. N Engl J Med. 1987;317(26):1625–9. DOI: 10.1056/NEJM198712243172603

11. Silverberg M.S., Satsangi J., Ahmad T., Arnott I.D., Bernstein C.N., Brant S.R., et al. Toward an integrated clinical, molecular and serological classification of inflammatory bowel disease: Report of a Working Party of the 2005 Montreal World Congress of Gastroenterology. Can J Gastroenterol. 2005;19 Suppl A:5A–36A. DOI: 10.1155/2005/269076

12. Hu B., Yang X.R., Xu Y., Sun Y.F., Sun C., Guo W., et al. Systemic immune-inflammation index predicts prognosis of patients after curative resection for hepatocellular carcinoma. Clin Cancer Res. 2014;20(23):6212–22. DOI: 10.1158/1078-0432.CCR-14-0442