KEY FACTS
Terminology
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Inflammation of liver due to viral infection or toxic agents
Imaging
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Acute: Enlarged liver
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Chronic: Decrease in liver size
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Grayscale ultrasound
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Acute hepatitis: Hepatomegaly and diffusely hypoechoic parenchyma (variably seen)
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Steatohepatitis and acute alcoholic hepatitis: Hepatomegaly and diffusely hyperechoic liver parenchyma
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Thickening of gallbladder wall
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Most pronounced in acute hepatitis A
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Starry-sky appearance: Portal triads appear markedly echogenic due to periportal edema against background hypoechoic liver (variably seen)
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May be related to periportal edema
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Pulsed Doppler ultrasound
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Elevated hepatic arterial velocity
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Top Differential Diagnoses
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Infiltrative hepatocellular carcinoma
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Lymphoma
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Steatosis (fatty liver)
Pathology
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Viral hepatitis: Caused by 1 of 5 viral agents
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Hepatitis A (HAV), B (HBV), C (HCV), D (HDV), E (HEV) viruses
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Alcohol abuse
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Autoimmune reactions
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Metabolic disturbances
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Toxic or drug-induced injury
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Exposure to environmental agents
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Radiation therapy
Scanning Tips
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Check for tender liver, which may be related to inflammation from acute hepatitis
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Check gain settings, which can affect appearance of liver and may mimic hepatitis or steatosis
