Δ4-3-Oxosteroid 5β-reductase deficiency: Failure of ursodeoxycholic acid treatment and response to chenodeoxycholic acid plus cholic acid

Abstract

Background - In some infants with liver disease, 3-oxo-Δ4 bile acids are the major bile acids in urine, a phenomenon attributed to reduced activity of the Δ4-3-oxosteroid 5β-reductase required for synthesis of chenodeoxycholic acid and cholic acid. These patients form a heterogeneous group. Many have a known cause of hepatic dysfunction and plasma concentrations of chenodeoxycholic acid and cholic acid that are actually greater than those of the 3-oxo-Δ4 bile acids. It is unlikely that these patients have a primary genetic deficiency of the 5β-reductase enzyme. Aims - To document the bile acid profile, clinical phenotype, and response to treatment of an infant with cholestasis, increased plasma concentrations of 3-oxo-Δ4 bile acids, low plasma concentrations of chenodeoxycholic acid and cholic acid, and no other identifiable cause of liver disease. Patients - This infant was compared with normal infants and infants with cholestasis of known cause. Methods - Analysis of bile acids by liquid secondary ionisation mass spectrometry and gas chromatography-mass spectrometry. Results - The plasma bile acid profile of the patient was unique. She had chronic cholestatic liver disease associated with malabsorption of vitamins D and E and a normal γ-glutamyltranspeptidase when the transaminases were increased. The liver disease failed to improve with ursodeoxycholic acid but responded to a combination of chenodeoxycholic acid and cholic acid. Conclusion - Treatment of primary 5β-reductase deficiency requires the use of bile acids that inhibit cholesterol 7α-hydroxylase.