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Isolation of Neonatal Extrahepatic Cholangiocytes
Published on: June 5, 2014
Prolonged Hyperbilirubinemia in a Neonate with a Novel Mutation in the UDP-glucuronosyltransferase 1A1 Gene
Shu-Chi Mu1, Yi-Ling Chen, Li-Yi Tsai
1Department of Pediatrics, Shin Kong Wu Ho-Su Memorial Hospital and School of Medicine, Fu-Jen Catholic University, Taipei, Taiwan, ROC.
Insights
This study details a male infant diagnosed with Gilbert's syndrome due to novel UDP-glucuronosyltransferase (UGT)1A1 gene mutations. Treatment with phototherapy and phenobarbital effectively managed hyperbilirubinemia.
Area of Science:
- Pediatrics
- Medical Genetics
- Biochemistry
Background:
- Neonatal hyperbilirubinemia is common, but persistent cases require etiological investigation.
- Elevated total bilirubin levels in infants can indicate underlying genetic or metabolic disorders.
- UDP-glucuronosyltransferase 1A1 (UGT1A1) gene variations are known causes of unconjugated hyperbilirubinemia.
Abstract:
The total bilirubin value of a male infant was 385 μmol/l on day 5. Liver function test results were normal and there was no evidence of sepsis and no hemolysis reaction. Phototherapy was administered and on day 8 the patient's total bilirubin level was 255 μmol/l. Intermittent episodes of hyperbilirubinemia occurred without phototherapy, with the total bilirubin level reaching 335 μmol/l on day 19. A 3-day regimen of phenobarbital was administered and on day 24 his total bilirubin level was 180 μmol/l. The patient was discharged. At the age of 2 months, the total bilirubin value was 27 μmol/l. His direct bilirubin value was <15% of total bilirubin in every determination. A family study of the UDP-glucuronosyltransferase(UGT)1A1 gene showed that the infant carries a homozygous mutation at nucleotide -3279 plus compound heterozygous mutations at nucleotides 782 and 1091. The mutation at nucleotide 782 is a novel finding. Gilbert's syndrome was diagnosed.
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