Successful treatment of an infant with congenital bile acid synthesis disorder type 3 by ursodeoxycholic acid: a case report.

BACKGROUND: Congenital bile acid synthesis disorder type 3 caused by oxysterol 7α-hydroxylase deficiency is an extremely rare genetic liver disease. As it may cause rapid progression to end-stage liver disease, a high cautiousness in diagnosis and early treatment are required. Here we describe the first case of congenital bile acid synthesis disorder type 3 in China that was confirmed by genetic analysis. CASE PRESENTATION: A 5-month-old Chinese male infant suffered skin yellowing since birth. The patient showed significantly increased alanine transaminase, aspartate transaminase, and total and direct bilirubin levels, and enlarged liver at admission. Whole-exome sequencing confirmed homozygous mutation in the CYB7B1 gene that encodes oxysterol 7α-hydroxylase. Ursodeoxycholic acid treatment significantly mitigated the condition of the patient and lowered biochemical indicators. Unfortunately, the patient developed septicemia and gave up treatment. CONCLUSIONS: The patient was successfully treated with ursodeoxycholic acid, which has not been reported previously. Ursodeoxycholic acid replacement therapy is an effective and affordable treatment for congenital bile acid synthesis disorder type 3 caused by oxysterol 7α-hydroxylase deficiency.

[Clinical and gene mutation analyses of three patients with ornithine carbamoyltransferase deficiency].

OBJECTIVE: To analyze the clinical and genetic characteristics of three children with ornithine carbamoyltransferase deficiency(OTCD), and to provide a practical method for gene diagnosis and genetic counseling of the disease. METHODS: All exons of the ornithine carbamoyltransferase (OTC) gene were screened by polymerase chain reaction-DNA direct sequencing in the three OTCD patients. RESULTS: One patient firstly presented as vomiting at 6 month of age. A missense mutation of T262I was detected. His mother had the same mutation without any clinical symptoms. The second patient presented as restlessness, and had a missense mutation of R277W. Gene analysis of his parents was not available. The third patient presented as neonatal lethargy, harbored a missense mutation of I172M. His mother had the same mutation without any clinical symptoms. CONCLUSION: Gene mutation analysis is a feasible way for diagnosing OTCD. Patients with I172M mutation present symptom early, while those with T262I and R277W mutations manifest symptoms later. Gene mutation analysis will be important for asymptomatic and prenatal diagnosis and genetic counseling.