A diagnostic score for biliary atresia

To the Editor:We read with great interest the paper by El-Guindi et al. [1],evaluating a new diagnostic score for biliary atresia (BA). BAis a destructive inflammatory obliterative cholangiopathy ofunknown origin that affects intra- and extrahepatic bile ducts.Success of surgical correction, in form of a Kasai portoenterosto-my amongst other factors, depends on early diagnosis and timelyintervention. Presently, there are no non-invasive diagnosticmethods that can clearly identify infants with BA from othercauses of neonatal cholestasis (NC). The current paradigm toexclude BA in any cholestatic infant hence requires evidence toprove patency of the extrahepatic bile duct [2–5]. To date, manyresearch groups have tried to improve the differential diagnosis[6] but none has yet reached sensitivity and specificity as highas in the present study. We are convinced that elements of theproposed scoring may help in the pre-selection of infants toundergo imaging of the extrahepatic bile duct. However we areconcerned that the study cohort of patients investigated mightbe skewed, thus limiting the diagnostic power of this score.(1) Entry criteria did not describe if there were children withdrug- or total parenteral nutrition-associated cholestasisor premature infants in the study population.(2) There was no information whether there were childrenwith the syndromic form of BA, with biliary stones,dilatation of bile ducts or choledochal cysts in the studycohort.(3) Important and common causes of NC, such as alpha-1antitrypsin deficiency, cystic fibrosis, bile acid syntheticdisorders, tyrosinemia type 1, galactosemia and hypopitu-itarism were not identified.(4) Normal or low values of gamma-glutamyl transpeptidase(GGT) in a child with NC imply a defect of bile excretionat the canalicular level. So it was not surprising that inthe group of non-BA patients the level of GGT was lowerthan in the BA group. There was no information aboutthe type of the progressive familial intrahepatic cholestasis(PFIC I or II) and whether the multi-drug resistance protein3 (MDR3) was examined.A variety of diseases can exactly mimic all separate features ofBA and only systematic evaluation of the entire spectrum willlead to a reliable diagnosis. Only innovative tools, such as nextgeneration sequencing, may possibly change this and contributeto a differential diagnosis in the future.Easy diagnosis of BA has been on the agenda for decades. But,despite all efforts, as long as we still do not understand theaetiology and triggering factors of BA we remain at risk ofmissing the correct diagnosis for a child with NC just based onnon-invasive diagnostics.Conflict of interestThe authors declared that they do not have anythingto disclosureregarding funding or conflict of interest with respect to thismanuscript.References