Background and aim: We encounter hyper-3-oxo-Delta(4) bile aciduria in patients with severe cholestatic liver disease or fulminant liver failure during the neonatal period. However, simply by bile acid analysis, it is difficult to distinguish hyper-3-oxo-Delta(4) bile aciduria from primary 3-oxo-Delta(4)-steroid 5beta-reductase deficiency.
Methods: To determine whether 3-oxo-Delta(4)-steroid 5beta-reductase (SRD5B1) gene analysis is required for the accurate diagnosis of 3-oxo-Delta(4)-steroid 5beta-reductase deficiency, we evaluated the laboratory data, bile acid analysis and SRD5B1 gene analysis from six patients with hyper-3-oxo-Delta(4) bile aciduria.
Results: Based upon the results, four patients who had developed neonatal liver failure were diagnosed as having neonatal hemochromatosis. Two patients with chronic cholestasis were diagnosed as having primary 3-oxo-Delta(4)-steroid 5beta-reductase deficiency by SRD5B1 gene analysis. The SRD5B1 gene in these two patients had a heterozygous mutation, G737A (Gly 223 Glu) in one patient and C217T (Arg 50 stop) in the other.
Conclusions: Based upon our limited data, we conclude that SDR5B1 gene analysis is required for the accurate diagnosis of 3-oxo-Delta(4)-steroid 5beta-reductase deficiency. Moreover, we think that it is important to elucidate whether there is a heterozygous or a compound heterozygous mutation of the SRD5B1 gene in our two patients.