Nomogram for assistant diagnosing acute suppurative cholangitis: a case-control study

Abstract Background: Acute suppurative cholangitis (ASC) lacks sensitive and specific preoperative diagnostic criteria. This study aimed to investigate the relationship between the grading system of acute cholangitis (AC) according to the Tokyo Guidelines 2018 (TG18) and the diagnosis of acute suppurative cholangitis (ASC), searching for independent risk factors of ASC and develop a nomogram to discriminate ASC from acute nonsuppurative cholangitis (ANSC) accurately. Methods: After applying the inclusion and exclusion criteria, 401 patients with acute cholangitis (AC) were retrospectively analyzed at Nanjing First Hospital between January 2015 and July 2023. Based on the presence of suppurative bile, the patients were divided into two groups. SPSS version 27.0 and R studio software were used to analyze data obtained from medical records. Results: Among the 401 patients, 102 had suppurative bile (the ASC group; AC grade I: 40 [39.2%], AC grade II: 27 [26.5%], AC grade III: 35 [34.3%]), whereas 299 did not have (the ANSC group; AC grade I: 157 [52.5%], AC grade II: 92 [30.8%], AC grade III: 50 [16.7%]). Multivariate logistic regression analysis identified concurrent cholecystitis, CRP, PCT, TBA, and bile duct diameter as independent risk factors for suppurative bile, and all of these factors were included in the nomogram. The calibration curve exhibited consistency between the nomogram and the actual observation, and the area under the curve was 0.875 (95% confidence interval: 0.835–0.915), sensitivity was 86.6%, and specificity was 75.5%. Conclusion: The nomogram demonstrated excellent predictive performance in assisting in diagnosing ASC.