Preoperative Clinical Scores for Predicting Complicated Appendicitis İn Surgically Managed Adults: Comparative Performance of Alvarado, Ripasa, and Lintula

Background Objectives: Clinical scoring systems are frequently used to support decision-making in suspected acute appendicitis; however, their value for severity stratification is less well defined. We compared the diagnostic performance of the Alvarado, RIPASA, and Lintula scores in a surgically managed adult cohort and examined their relationship with histopathological subtypes. Methods: This retrospective observational study included 312 adults who underwent appendectomy for suspected acute appendicitis between May 2024 and April 2025 at Amasya University Şerefeddin Sabuncuoğlu Training and Research Hospital.Clinical variables recorded at emergency department presentation were used to derive Alvarado, RIPASA, and Lintula scores, which were calculated retrospectively from chart data. Histopathology served as the reference standard. Using literature-recommended cutoffs, sensitivity, specificity, positive and negative predictive values (PPV and NPV), accuracy, and the Youden index were calculated. Discrimination was assessed using the area under the receiver operating characteristic curve (AUC). Results: Mean age was 29.77 ± 9.55 years, and 58.7% were male. Laparoscopic appendectomy was performed in 97.8% of cases. Appendicitis was confirmed histologically in 90.1%, with phlegmonous (49.4%), gangrenous (22.4%), and perforated (18.3%) subtypes; the negative appendectomy rate was 9.9%. At standard thresholds, sensitivity/specificity were 67.3%/71.0% (Alvarado), 76.1%/77.4% (RIPASA), and 70.1%/64.5% (Lintula). PPV was high (94.7%–96.8%), whereas NPV was low (19.2%–26.4%). AUC values were 0.765, 0.857, and 0.829 for Alvarado, RIPASA, and Lintula, respectively. Mean scores increased with histopathological severity (p < 0.001). In perforation-focused analysis, RIPASA showed the highest AUC (0.922). Conclusions: In this surgically managed cohort, all three scores demonstrated strong rule-in performance when positive. RIPASA showed the highest overall discrimination and favourable performance in perforation-focused analysis. Nevertheless, the consistently low NPV limits their utility as standalone rule-out tools; scoring systems should be interpreted alongside clinical assessment and imaging.