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Essentials of Diagnosis
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Results from accumulation of bilirubin in body tissues; the cause may be hepatic or nonhepatic
Hyperbilirubinemia may be due to abnormalities in the formation, transport, metabolism, or excretion of bilirubin
Persistent mild elevations of the aminotransferase levels are common in clinical practice and caused most often by nonalcoholic fatty liver disease
Evaluation of obstructive jaundice begins with ultrasonography and is usually followed by cholangiography
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General Considerations
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May be caused by predominantly unconjugated or conjugated bilirubin in the serum (Table 16–1)
In the absence of liver disease, hemolysis rarely elevates the serum bilirubin level to more than 7 mg/dL (119.7 mcmol/L)
"Cholestasis" denotes retention of bile in the liver, and "cholestatic jaundice" implies conjugated hyperbilirubinemia from impaired bile flow
Mediators of pruritus due to cholestasis have been identified to be lysophosphatidic acid (LPA) and autotaxin, the enzyme that forms LPA
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