Unbound bilirubin associated with kernicterus: a historical approach.

Abstract

OBJECTIVE:

To determine the unbound bilirubin concentration (UBC) associated with kernicterus with the use of clinical data from clusters of kernicterus after sulfisoxazole and benzyl alcohol administration.

DESIGN:

Sulfisoxazole at 12 mg/dL and benzoate at 10 mmol/L are associated with kernicterus at total bilirubins near 12 and 10 mg/dL, respectively. The concurrent UBC was estimated by first measuring the drug-induced increases in UBC in plasma and artificial sera (peroxidase-diazo method). The increases were then applied to baseline UBC, determined by linear regression analysis of binding data (peroxidase method) from 86 newborns, at total bilirubins of 12 mg/dL for sulfisoxazole and 10 mg/dL for benzoate. Sensitivity and specificity were determined with existing data.

RESULTS:

Sulfisoxazole and benzoate increased UBC in artificial sera 2.1-fold and 4.1-fold, respectively, and in plasma (sulfisoxazole) 2.4-fold. Benzoate would increase baseline UBC from 0.29 to 1.19 microg/dL and sulfisoxazole from 0.36 to 0.86 microg/dL. The sensitivity and specificity of a UBC of 0.86 microg/dL for predicting kernicterus are 79% and 92% and for 1.19 microg/dL, 50% and 98%, respectively.

CONCLUSION:

Historic data predict that the unbound bilirubin above which kernicterus becomes likely lies between 0.86 and 1.19 microg/dL, in good agreement with existing information.

• Authors: C E Ahlfors
• Journal: The Journal of pediatrics (J Pediatr) Vol. 137 Issue 4 Pg. 540-4 (Oct 2000) ISSN: 0022-3476 [Print] United States
• PMID: 11035835 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Sulfisoxazole
• Benzyl Alcohol
• Bilirubin

Topics

• Benzyl Alcohol (pharmacology)
• Bilirubin (blood)
• Humans
• Infant, Newborn
• Kernicterus (blood)
• Sulfisoxazole (pharmacology)