Gamma-Glutamyl Transferase Combined with Conventional Ultrasound Features in Diagnosing Biliary Atresia: A Two-Center Retrospective Analysis

Background: Although ultrasound examination can help diagnose biliary atresia (BA), there are still some infants with BA who lack typical ultrasound findings that cannot be detected by ultrasound. The purpose of this study was to develop and validate a BA diagnostic score based on serum gamma-glutamyl transferase (GGT) levels and conventional ultrasound features for discriminating BA in patients with jaundice from two centers.Methods: A total of 958 patients from one hospital were classified as the derivation cohort, and 725 patients from another hospital were classified as the validation cohort. The optimal GGT cutoff value for the diagnosis of BA was calculated in the derivation cohort and subsequently verified in the validation cohort. Gallbladder abnormalities and the triangular cord (TC) sign were evaluated in all patients. A BA diagnostic score was developed for diagnosing BA using the logarithmic transformations of GGT levels, gallbladder abnormalities and the TC sign based on the data from the derivation cohort followed by external validation.Findings: Based on the optimal cutoff value 350.0 U/L, GGT yielded a sensitivity of 59.3% and specificity of 85.4% in diagnosing BA. Nine infants with BA were misdiagnosed by ultrasound but diagnosed correctly by GGT. The BA diagnostic score yielded a sensitivity of 93.3% and specificity of 95.0% with the highest AUC in this study (0.941).Interpretation: GGT can add diagnostic value to ultrasound examination when diagnosing BA. The BA diagnostic score based on GGT, gallbladder abnormalities and the TC sign shows satisfactory discrimination abilities in BA.Funding: This work was supported by Guangdong Basic and Applied Basic Research Foundation (grant numbers: 2019A1515010549) and Sponsored by Fujian Provincial Health Technology Project (grant numbers: 2020GGB015).Declaration of Interest: None to declare. Ethical Approval: This study was approved by the ethics committee of the First Affiliated Hospital of Sun Yat-sen University. Due to its retrospective design, written informed parental consent was waived.