Simple Biliary Atresia Score - A Validated Diagnostic Aid for Infantile Cholestasis

Purpose The work-up of jaundiced infants may be variable and protracted, thereby delaying the diagnosis and timely intervention for biliary atresia (BA). This potentially leads to inferior outcomes. We developed a practical score to stratify infantile cholestasis according to the risk of having BA. Method The score (0-7)[gallbladder length ≤15mm(+1), common-bile-duct (CBD) diameter <0.5mm(+1), pre-portal vein (PV) echogenicity(+1), direct-to-total bilirubin ratio (D/T) ≥0.7(+2) and gamma-glutamyl-transferase (GGT) ≥200IU/L(+2)] is derived from logistic regression of data from a retrospective cohort of cholestatic infants (n=58, 41 BA) in our institution. It was then validated with a separate retrospective cohort (n=28, 17 BA) from another institution. Final diagnoses were as per intraoperative cholangiogram (IOC) and liver histopathology. Results A cut-off score of ≥3 diagnosed BA with 100% and 94% sensitivity in the derivative cohort (area-under-Receiver-Operating-Characteristic-curve, AUROC 0.869) and validation cohort (AUROC 0.807) respectively. D/T ratio was the most sensitive (93%) and CBD diameter was the most specific (88%) parameter. The score accurately predicted non-BA in 11(65%) and 7(63%) infants in the derivative and validation cohorts respectively, with one missed BA in the latter. Conclusion We propose a validated, simple, yet sensitive diagnostic score to risk-stratify cholestatic infants, aiming to expedite definitive management of BA.