Abstract:Objective To construct and validate a predictive model for intravenous immunoglobulin (IVIG) resistance in children with Kawasaki disease (KD) based on Lasso regression and nomogram, aiming to assist clinical diagnosis and treatment.Methods Clinical data from 474 children with KD treated at the Affiliated Hospital of Southwest Medical University from July 2014 to July 2020 were retrospectively collected. Lasso regression analysis was used to select important clinical factors to build the Nomogram model. The model's discrimination, calibration, and clinical effectiveness were verified through the receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA).Results A total of 474 cases were included, with 339 cases in the training set and 135 cases in the validation set. Lasso regression analysis identified cardiac manifestations, extracardiac complications, time of first intravenous immunoglobulin use, neutrophil ratio, red cell distribution width-standard deviation, platelet crit, albumin, systemic immune-inflammatory index, and C-reactive protein/albumin as predictive factors for IVIG resistance in children with KD. A Nomogram model was constructed based on these predictive factors and validated in both the training and validation sets. The area under the ROC curve (AUC) in the training set was 0.784 (95% CI: 0.701, 0.867), with a specificity of 0.490 (95% CI: 0.434, 0.546) and sensitivity of 0.935 (95% CI: 0.849, 1.000) at the optimal threshold of 0.045. The AUC in the validation set was 0.784 (95% CI: 0.643, 0.925), with a specificity of 0.851 (95% CI: 0.788, 0.915) and sensitivity of 0.714 (95% CI: 0.478, 0.951) at the optimal threshold of 0.142. The C-values in the calibration curve for the training and validation sets were 0.784 and 0.784, with P-values of 0.953 and 0.251, respectively. The DCA curve showed a clinical net benefit in the training set when the threshold probability (Pt) ranged from 0.01 to 0.58.Conclusion The Lasso regression Nomogram model for predicting IVIG resistance in KD is convenient for clinical use and helps identify high-risk children for IVIG resistance early.