The duodenal tube test is more specific than hepatobiliary scintigraphy for identifying bile excretion in the differential diagnosis of biliary atresia.

Confirmation of bile excretion into the gastrointestinal tract is important to exclude biliary atresia (BA). We compared the duodenal tube test (DTT) with hepatobiliary scintigraphy (HS) for their efficiency in detecting bile secretion. The subjects of this retrospective study were 47 infants who underwent both DTT and HS to diagnose or exclude BA between January 2000 and March 2018. BA was diagnosed in 32 of the 47 patients, and 7 of the remaining 15 non-BA patients underwent intraoperative cholangiography. Among the various DTT parameters, the total bile acid in duodenal fluid (DF-TBA)/serum (S) gamma-glutamyl transferase (γGTP) ratio was found to be the most specific for BA, with sensitivity and specificity of 98.0-100%, respectively. One BA patient in whom cut off values were not met was a premature infant. The sensitivity and specificity of HS were 100-56.3%, respectively. The diagnostic accuracy of the DF-TBA/S-γGTP parameter was higher than that of HS (98.6% vs. 85.1%, respectively). The DTT could be more a specific method than HS to detect bile excretion. Thus, the DTT should be incorporated into the multidisciplinary diagnostic approach for the differential diagnosis of BA to prevent unnecessary intraoperative cholangiography in patients who do not have BA.