rss
Arch Dis Child Fetal Neonatal Ed 2005;90:F123-F127 doi:10.1136/adc.2004.058313
  • Original article

Neonatal bilirubin production-conjugation imbalance: effect of glucose-6-phosphate dehydrogenase deficiency and borderline prematurity

  1. M Kaplan1,2,
  2. M Muraca4,*,
  3. H J Vreman6,
  4. C Hammerman1,3,
  5. M T Vilei4,
  6. F F Rubaltelli5,
  7. D K Stevenson6
  1. 1Department of Neonatology, Shaare Zedek Medical Center, Jerusalem, Israel
  2. 2Faculty of Medicine, Hebrew University, Jerusalem, Israel
  3. 3Faculty of Health Sciences, Ben Gurion University of the Negev, Be’er Sheva, Israel
  4. 4Department of Internal Medicine, University of Padua, Florence, Italy
  5. 5Department of Neonatology, University of Florence, Florence, Italy
  6. 6Division of Neonatal and Developmental Medicine, Department of Pediatrics, Stanford University Medical Center, Stanford, CA, USA
  1. Correspondence to:
    Dr Kaplan
    Department of Neonatology, Shaare Zedek Medical Center, PO Box 3235, Jerusalem 91031, Israel; kaplancc.huji.ac.il
  • Accepted 7 October 2004

Abstract

Objective: To evaluate relations between production and conjugation of bilirubin in the pathophysiology of jaundice in glucose-6-phosophate dehydrogenase (G6PD) deficient neonates.

Methods: Term and borderline premature (35–37 weeks gestational age), healthy, male, G6PD deficient neonates were studied close to the beginning of the 3rd day. Blood carboxyhaemogobin corrected for inspired CO (COHbc; an index of bilirubin production) and serum total conjugated bilirubin (TCB; a reflection of bilirubin conjugation) were measured in simultaneously drawn blood samples by gas chromatography and reverse phase high performance liquid chromatography respectively. A bilirubin production-conjugation index comprising COHbc/TCB was determined; a high index reflects imbalance between the bilirubin production and conjugation processes. COHbc and TCB individually and the production-conjugation index were studied in relation to serum total bilirubin (STB) concentration.

Results: Fifty one G6PD deficient neonates were sampled at 51 (8) hours. COHbc values did not correlate with STB (r  =  0.22, p  =  0.15). TCB did correlate inversely with STB (r  =  −0.42, p  =  0.004), and there was a positive correlation between the production-conjugation index and STB (r  =  0.45, p  =  0.002). The production-conjugation index (median (interquartile range)) was higher in the premature (n  =  8) than term neonates (2.31 (2.12–3.08) v 1.05 (0.53–1.81), p  =  0.003). This difference was the result of changes in TCB.

Conclusions: The data show that jaundice in G6PD deficient neonates is the result of an imbalance between production and conjugation of bilirubin with a tendency for inefficient bilirubin conjugation over increased haemolysis in its pathogenesis. Borderline premature infants are at especial risk of bilirubin production-conjugation imbalance.

Footnotes

  • * Present address: Clinical Chemistry Laboratory, Ospedale Pediatrico Bambino Gesu, Piazza Sant’ Onofrio 4, 00165 Rome, Italy

  • Competing interests: none declared

  • Presented in part at the Pediatric Academic Societies’ Annual Meeting, Seattle, WA, USA, 3–6 May, 2003.

Register for free content

The full back archive is now available for all BMJ Journals. Institutional subscribers may access the entire archive as part of their subscription. Personal subscribers will also have access to all content when logged in. Non-subscribers who register have free access to all articles published before 2006 right back to volume 1 issue 1. Register here to access the free archive of all BMJ Journals.

Don't forget to sign up for content alerts so you keep up to date with all the articles as they are published.