We present a case of severe persisting unconjugated hyperbilirubinemia in a Uigur infant boy, eventually diagnosed as Crigler-Najjar syndrome type I. DNA analysis of his blood of the UGT1A1 gene sequence demonstrated that he was homozygous for an insertion mutation causing a change of the coding exons with a frame-shift, resulting in the substitution of 27 abnormal amino acid residues in his hepatic bilirubin uridine diphosphoglucuronyl transferase enzyme. Both of his parents were heterozygous for the same mutation. A novel frame-shifting mutation of the UGT1A1 gene was found, confirming the diagnosis of Crigler-Najjar syndrome type I for this patient.
Crigler-Najjar Syndrome ; diagnosis ; genetics ; Frameshift Mutation ; genetics ; Glucuronosyltransferase ; genetics ; Humans ; Infant, Newborn ; Male

OBJECTIVETo detect potential mutation of the UGT1A1 gene in a child affected with Crigler-Najjar syndrome type II.

METHODSBlood samples were collected from the patient and his parents for the extraction of genomic DNA. Potential mutation of the UGT1A1 gene was detected with polymerase chain reaction (PCR) and direct sequencing. The child was followed up until the age of 3 years and 6 months.

RESULTSThe patient showed persistent unconjugated hyperbilirubinemia. Sequencing of the UGT1A1 gene has detected a rare heterozygous c.610 A>G (p.Met204Val) mutation in the exon 1, in addition with a heterozygous c.1091 C>T (p.Pro364Leu) mutation in exon 4. The two mutations were inherited from his father and mother, respectively. The patient was diagnosed with Crigler-Najjar syndrome type II and received oral phenobarbital treatment.

CONCLUSIONThe compound UGT1A1 gene mutation probably accounts for the disease in the patient manifesting persistent mild unconjugated hyperbilirubinemia. Genetic counseling and prenatal diagnosis should be provided for his family.

Crigler-Najjar Syndrome ; genetics ; Glucuronosyltransferase ; genetics ; Humans ; Infant ; Male ; Mutation ; Sequence Analysis, DNA

Patients with co-existing hereditary spherocytosis (HS) and UDP-glucuronosyltransferase 1A1 (UGT1A1) deficiency as Gilbert's syndrome (GS) have been reported, and previous studies have demonstrated an increased risk for developing gallstones in patients with co-inheritance of GS and HS. We experienced an interesting case of HS showing persistent jaundice after splenectomy, and upon further evaluation, the 25-year-old female patient was found to have HS combined with UGT1A1 deficiency. Sequence analysis of the UGT1A1 gene revealed that she was a compound heterozygote with p.[G71R; Y486D] + [Y486D] mutations, which suggests Crigler-Najjar syndrome type II rather than GS. Careful evaluation of inappropriately elevated bilirubin level compared with the degree of hemolysis is important, reflecting the therapeutic implication of splenectomy and cholecystectomy.
Adult ; Crigler-Najjar Syndrome/genetics ; Female ; Glucuronosyltransferase/*deficiency/genetics ; Heterozygote ; Homozygote ; Humans ; Jaundice/etiology/genetics ; Mutation, Missense/genetics ; Point Mutation/genetics ; Spherocytosis, Hereditary/complications/*genetics ; Splenectomy/adverse effects

Crigler-Najjar Syndrome ; genetics ; Gilbert Disease ; genetics ; Glucosephosphate Dehydrogenase Deficiency ; genetics ; Glucuronosyltransferase ; genetics ; Humans ; Infant, Newborn ; Jaundice, Neonatal ; genetics ; Polymorphism, Genetic