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Urinary tract infections in infants: comparison between those with conjugated vs unconjugated hyperbilirubinaemia

Hung-Chang Lee1, Shiuh-Bin Fang, Chun-Yan Yeung

  • 1Department of Paediatrics, Mackay Memorial Hospital, Taiwan; Department of Paediatrics, Taipei Medical Uinversity, Taiwan.

Annals of Tropical Paediatrics
|November 22, 2005
PubMed

Insights

In young infants with urinary tract infections (UTI), unconjugated hyperbilirubinaemia can occur early. After six weeks, conjugated hyperbilirubinaemia is common, often linked to anemia and liver enzyme elevation.

Area of Science:

  • Neonatal Medicine
  • Pediatric Gastroenterology
  • Infectious Diseases

Background:

  • Prolonged jaundice in infants can be a sign of underlying conditions.
  • Urinary tract infections (UTI) are common in young infants and can present with jaundice.

Purpose of the Study:

  • To investigate the association between conjugated and unconjugated hyperbilirubinaemia and urinary tract infections (UTI) in young infants.
  • To differentiate clinical characteristics of infants with conjugated versus unconjugated hyperbilirubinaemia in the context of UTI.

Main Methods:

  • Retrospective analysis of 50 infants (<3 months) with prolonged jaundice and UTI from 1984-2004.
  • Categorization into conjugated (n=22) and unconjugated (n=28) hyperbilirubinaemia groups.
  • Comparison of clinical variables including hemoglobin, liver enzymes, age, jaundice duration, and causative pathogens.

Main Results:

  • Conjugated hyperbilirubinaemia group showed lower hemoglobin, higher AST/ALT, older age at admission, and longer jaundice duration.
  • Escherichia coli (E. coli) infections were more frequent in the conjugated group (19/22 vs 15/28).
  • Direct/total bilirubin ratio correlated with jaundice duration; jaundice >38 days suggested conjugated type, and >44 days made unconjugated type unlikely.

Conclusions:

  • Young infants with UTI can present with unconjugated hyperbilirubinaemia early on.
  • After six weeks of age, jaundice in infants with UTI is typically conjugated.
  • Conjugated hyperbilirubinaemia in this cohort was frequently associated with anemia, elevated hepatic aminotransferases, and E. coli infections.
Abstract

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