Cytomegalovirus infection in inflammatory bowel disease: Clinical,endoscopic and histopathological evaluation

Introduction and Objective:This study aimed to evaluate the relationship between cytomegalovirus (CMV) positivity and clinical, biochemical, and histopathological parameters in patients with inflammatory bowel disease (IBD), and to determine the potential impact of CMV infection on disease course and prognosis. Methods:A total of 134 patients diagnosed with IBD were included in this retrospective study. CMV positivity was confirmed using immunohistochemical (IHC) staining. Patients were classified into three groups—negative, low-positive, and high-positive—based on the number of CMV-positive cells per mm² and per tissue section. Demographic, clinical, and laboratory data were analyzed using the Chi-square test, Bonferroni-adjusted pairwise comparisons, and logistic regression analysis to determine associations between variables. Results:Statistically significant associations were identified between CMV positivity and age, creatinine levels, anti TNF therapy, and hospitalization (p<0.05). CMV-positive patients had significantly higher age and creatinine values compared to CMV-negative patients. Logistic regression analysis revealed that hospitalization increased the risk of CMV positivity by 13.692-fold, elevated creatinine by 10.292-fold, and each one-year increase in age by 6.2% (OR=1.062, p<0.05). No significant association was found between CMV positivity and azathioprine, steroid, or ASA use (p>0.05). Histopathological evaluation showed significantly higher creatinine levels in the high-positive group and a predominance of male patients (χ²=6.829; p=0.033). The neutrophil-to-lymphocyte ratio (NLR) was significantly higher in CMV-negative patients compared to CMV-positive ones. Conclusion:This study demonstrates that CMV infection in IBD patients is not merely a coincidental finding but an active determinant influencing clinical and biochemical outcomes. Quantitative histological parameters—the number of CMV-positive cells per mm² and per tissue section—provide a more objective assessment of viral load and its tissue-level impact. Higher age, increased creatinine levels, anti TNF therapy, and hospitalization were identified as significant risk factors for CMV positivity. Therefore, routine CMV screening and histological quantification are recommended, particularly in IBD patients with severe disease or those receiving immunosuppressive or biological therapy. CMV should be regarded as an active clinical risk marker in the management of IBD, and histological burden should be considered when determining antiviral treatment strategies.