Normal Reference Ranges
Adult
15 - 45 mcg/dL
Pediatric
40 - 80 (Newborns much higher) mcg/dL
Clinical Significance
Byproduct of protein catabolism. Toxic to the CNS. Elevated levels correlate roughly with the severity of hepatic encephalopathy.
Causes of High
- Hepatic encephalopathy
- Severe liver failure (Cirrhosis, Fulminant hepatitis)
- Reye syndrome
- GI bleeding with liver disease
Causes of Low
- Normal finding