Up to two-thirds of biliary atresia (BA) patients need liver transplantation after the standard Kasai portoenterostomy treatment. Unrelenting cholangitis often precedes the full-blown presentation of BA. Using ribosomal 18S sequencing, here we report bowel colonization by non-commensal Aspergillus fungi in one case of neonatal obstructive cholangitis. Continuous oral fluconazole treatment resolved obstructive cholangitis completely. Colonization by non-commensal Aspergillus and Cerrena were additionally identified in 2 BA cases. In brief, bowel colonization by non-commensal fungi could be a treatable cause of neonatal obstructive cholangitis and potentially BA at an early stage.

The authors have declared no competing interest.

This study did not receive any funding.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

IRB of National Taiwan University Children's Hospital and En Chu Kong Hospital gave ethical approval for this work.

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All data produced in the present study are available upon reasonable request to the authors.