Evaluation of jaundice caused by unconjugated hyperbilirubinemia in children
- Oranit Shaked, MD
Oranit Shaked, MD
- Assistant Professor, Pediatrics
- Wertheim College of Medicine
- Barbara M Peña, MD, MPH
Barbara M Peña, MD, MPH
- Associate Professor
- Wertheim College of Medicine
Jaundice is a yellowish discoloration of the skin and sclerae that is an important symptom of elevated serum bilirubin, which is caused by an abnormality of bilirubin metabolism or excretion. The bilirubin can be either unconjugated or conjugated. Conjugated bilirubin is water soluble and is also known as "direct" bilirubin. Disorders causing unconjugated hyperbilirubinemia are more common in children, and are largely distinct from those causing conjugated hyperbilirubinemia. However, some diseases increase both unconjugated and conjugated bilirubin because they affect several different aspects of hepatocyte function.
This topic will present an overview of the causes of unconjugated hyperbilirubinemia in children and infants beyond the neonatal period and discuss the evaluation and management of such patients, which varies with the underlying disease.
The evaluation of unconjugated hyperbilirubinemia in neonates and the causes and diagnostic approach for the adult with jaundice, which are somewhat different, are discussed separately. (See "Evaluation of unconjugated hyperbilirubinemia in term and late preterm infants" and "Diagnostic approach to the adult with jaundice or asymptomatic hyperbilirubinemia" and "Classification and causes of jaundice or asymptomatic hyperbilirubinemia".)
●Hyperbilirubinemia refers to elevated serum total bilirubin. After the neonatal period, the upper limit of normal is >1 mg/dL (17 micromol/L), or >1.3 mg/dL (22 micromol/dL) in some laboratories. Jaundice usually becomes clinically apparent when the serum total bilirubin concentration is greater than 2 to 3 mg/dL (34 to 51 micromol/L), but threshold for clinically apparent jaundice may vary among patients.
Hyperbilirubinemia can be further categorized as conjugated or unconjugated; these categories have important diagnostic implications:To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information on subscription options, click below on the option that best describes you:
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- CAUSES OF UNCONJUGATED HYPERBILIRUBINEMIA
- Bilirubin overproduction
- - Extravascular hemolysis
- - Intravascular hemolysis
- - Other
- Impaired hepatic bilirubin uptake
- - Reduced hepatic blood flow
- - Drugs
- Impaired bilirubin conjugation
- - Gilbert syndrome
- - Crigler-Najjar syndrome
- - Drugs
- - Other
- DIAGNOSTIC APPROACH
- HISTORY AND PHYSICAL EXAMINATION
- Physical examination
- LABORATORY TESTING
- Unconjugated hyperbilirubinemia with anemia and/or hemolysis
- Unconjugated hyperbilirubinemia without anemia or hemolysis
- Other results
- SOCIETY GUIDELINE LINKS
- INFORMATION FOR PATIENTS
- SUMMARY AND RECOMMENDATIONS