Novel mutation in the HSD3B7 gene causes bile acid synthetic disorder and presents as recurrent liver failure in early childhood

Bile acid synthetic disorders are rare inborn errors of metabolism, and presentations include neonatal cholestasis, neurological disease or deficiency of fat-soluble vitamins. Affected patients fail to produce standard bile acids but accumulate unusual bile acids and intermediates, resulting in liver failure and complications. Most of them improve with bile acid supplementation, but delaying initiating treatment is detrimental to the outcome. A young child presented to us with recurrent episodes of acute liver failure. In the first episode, both coagulopathy and encephalopathy improved on supportive treatment, but the aetiological evaluation was inconclusive. During the second presentation, whole-exome sequencing was sent, identifying a compound heterozygous novel mutation in the 3-β-hydroxysteroid dehydrogenase type 7 gene leading to bile acid synthetic defect.