Predictive Value of Abdominal CT Images Combined With Serological Indicators for Ureteral Involvement in Idiopathic Retroperitoneal Fibrosis.

Objective To analyze the value of abdominal CT images combined with serological indicators in predicting the ureteral involvement in idiopathic retroperitoneal fibrosis(IRF). Methods The CT images of 79 IRF patients were analyzed retrospectively,including the involved sites and enhancement characteristics of the lesions.According to the inclusion and exclusion criteria,43 patients with complete serological data were selected and assigned into a ureteral involvement group(n=29)and a non-ureteral involvement group(n=14) according to whether ureters were involved in IRF.Logistic regression analysis was performed to select independent risk factors for ureteral involvement in IRF.The receiver operating characteristic(ROC)curve was plotted to evaluate the predictive value of the CT arterial phase enhancement magnitude and serum cystatin C(CysC)for ureteral involvement in IRF. Results The CT images of IRF usually showed a soft tissue density lesion encompassing the abdominal aorta,iliac arteries,ureters,and retroperitoneal tissue,with a wide range of distribution.The ureteral involvement group and the non-ureteral involvement group showed differences in gender(P=0.031),CT arterial phase enhancement amplitude(P=0.014),CT venous phase enhancement amplitude(P=0.032),and serum CysC(P=0.036).Logistic regression analysis showed that gender(P=0.034),CT arterial phase enhancement amplitude(P=0.046),and serum CysC(P=0.041)were independent risk factors for ureteral involvement in IRF.The area under the curve for CT arterial phase enhancement combined with serum CysC to predict ureteral involvement in IRF was 0.776.Ten patients had lower levels of erythrocyte sedimentation rate(P<0.001),C-reactive protein(P=0.021),and IgG4(P<0.001)in the follow-up period than before treatment. Conclusion The combination of abdominal CT images with serological indicators demonstrates high accuracy in predicting the ureteral involvement in IRF,providing reference for early clinical diagnosis.