Utilizing non-invasive biomarkers for early and accurate differentiation of uncomplicated and complicated acute appendicitis: a retrospective cohort analysis

Acute appendicitis is a common condition requiring surgical intervention, with a lifetime risk of 7-8%. Differentiating between uncomplicated and complicated appendicitis is essential for appropriate treatment and improved patient outcomes. This study aimed to utilize minimal, non-invasive data to distinguish between these forms of appendicitis, using advanced analytical methods for faster and more precise diagnosis. This retrospective study analyzed acute appendicitis cases from January 2018 to December 2022 at a tertiary care hospital. Data were gathered from 3,045 patients, including demographic details, clinical features, laboratory tests (Red Cell Distribution Width [RDW] and Mean Platelet Volume [MPV]), and imaging results. Patients were classified as having uncomplicated or complicated appendicitis based on surgical and histopathological findings. Statistical analyses, including multivariate logistic regression and ROC curve analyses, were performed using SPSS. Complicated appendicitis was defined based on surgical findings and histopathological criteria, including perforation, abscess formation, or gangrene. Uncomplicated appendicitis was defined as inflammation confined to the appendix without evidence of perforation or abscess. The study population comprised 1,869 males (61.37%) and 1,176 females (38.62%), with a mean age of 36.4 years. The mean RDW was 27.81%, and the mean MPV was 8.68 fL. Among the appendectomy cases, 50.7% were acute appendicitis, 10.3% were negative appendectomies, and 38.9% had complicated appendicitis. RDW was significantly higher in acute appendicitis than in negative cases (t = 2.45, p = 0.02) and even higher in complicated cases (t = 3.78, p = 0.001). MPV was highest in complicated appendicitis, consistent with increased inflammation severity (t = 2.56, p = 0.01). The sensitivity and specificity of RDW for identifying complicated appendicitis were 0.85 and 0.75, respectively, and for MPV, they were 0.80 and 0.70. Univariate logistic regression identified male sex and appendix diameter as significant predictors of complicated appendicitis. In multivariate analysis, appendix diameter remained significant (p = 0.01), and male sex approached significance (p = 0.06). The optimal cutoff for appendix diameter to differentiate appendicitis types was 10 mm, with an AUC of 0.82. RDW, MPV, and appendix diameter provide a reliable method for distinguishing between uncomplicated and complicated appendicitis. Combining these biomarkers enhances diagnostic accuracy and enables precise risk stratification for better patient management.