Background:

Inborn errors in bile acid synthesis are a group of genetic defects accounting for 1 to 2% of chronic cholestatic diseases in infants, children and adolescents. Deficiency of 3β-Δ5-C27-hydroxysteroid dehydrogenase (3β-HSDH) is the most common defect in this disease. Clinical features consist of neonatal hepatitis, hepatomegaly, splenomegaly, malabsorption, malnutrition, and late-onset liver disease.

Case report:

A male infant who presented jaundice in sclera at 4 months that resolved spontaneously, later presented cholestatic disease at 18 months. During his approach, normal gamma-glutamyl transpeptidase was documented, a finding that is highly suggestive of alteration in the synthesis of bile acids. The diagnosis was made using urine mass spectrometry. Oral colic acid treatment was started, presenting immediate improvement.

Conclusions:

The result in urinary bile acids is definitive for the genetic defect and consistent with homozygous mutations in the HSD3B7 gene. This condition is a diagnosis of exclusion in childhood cholestatic diseases, particularly in the presence of normal or mildly enlarged gamma-glutamyl transpeptidase, and responds adequately to oral treatment; it should be identified early.