Development and validation of a prediction model for cholangitis after percutaneous transhepatic cholangioscopic lithotripsy

Cholangitis is a common complication of percutaneous transhepatic cholangioscopic lithotripsy (PTCSL) for hepatolithiasis, but risk assessment tools are lacking. This study aimed to identify predictors of cholangitis after PTCSL and develop a predictive nomogram. This retrospective study analysed 245 patients who underwent 450 PTCSL sessions between 1 January 2016 and 1 January 2024. All sessions demonstrating cholangitis complications were classified into the cholangitis group, while the remaining sessions were classified into the non-cholangitis group. All the sessions were divided into training and validation sets. Least absolute shrinkage and selection operator (LASSO) analysis was conducted to preliminarily select predictors of cholangitis complications. Multivariable logistic regression was performed to identify factors for constructing the nomogram. Cholangitis was diagnosed in 51 patients (62 sessions), for an incidence of 13.78% (62 among 450 sessions). Three characteristic variables were included in the model: operation technique (odds ratio [OR] = 0.235, 95% confidence interval [CI]: 0.105-0.524, p < 0.001), globulin (OR = 1.077, 95%CI:1.026-1.131, p = 0.003), and postoperative prophylactic dexamethasone (OR = 0.286, 95%CI:0.145-0.564, p < 0.001). The area under the curve (AUC) for the nomogram was 0.749 (95% CI, 0.673-0.826) in the training set and 0.721 (95% CI, 0.593-0.849) in the validation set, demonstrating relatively high discriminability. The calibration curves demonstrated the consistency between the predicted and actual values. Decision curve analysis indicated that the nomogram offers net clinical benefits. Operation technique, globulin, and postoperative prophylactic dexamethasone may predict cholangitis after PTCSL. We developed a nomogram to estimate the risk of post-PTCSL cholangitis, which demonstrated good predictive performance.