Liver zone 1 vulnerability vs Liver zone 2 and zone 3 vulnerability
How to tell Liver zone 1 vulnerability and Liver zone 2 and zone 3 vulnerability apart when a board question makes them look alike.
Zone 1 is periportal and oxygen-rich; zone 2 is yellow fever; zone 3 is centrilobular, low oxygen, and CYP-toxic.
Side by side
Liver zone 1 near portal triad receives most oxygen and nutrients and is vulnerable to viral hepatitis and phosphorus poisoning patterns.
Zone 2 midzonal injury is classic for yellow fever; zone 3 is centrilobular, high CYP450/low oxygen, and vulnerable to acetaminophen toxicity and ischemia.
Liver zone 1 near portal triad receives most oxygen and nutrients and is vulnerable to viral hepatitis and phosphorus poisoning patterns.
Zone 2 sits between periportal and centrilobular blood supply and is classically injured in yellow fever; zone 3 receives least oxygen and has high CYP metabolism.
The trap
Zone 1 is periportal oxygen-rich; zone 3 is centrilobular low oxygen and high CYP toxin metabolism.
The repair move
Before naming the answer, force the stem through the separator: Zone 1 is periportal oxygen-rich; zone 3 is centrilobular low oxygen and high CYP toxin metabolism.
Try a free question
CoreA patient with viral hepatitis B has liver biopsy showing PERIPORTAL inflammation and hepatocyte damage in the region near the portal triad. The injured cells are in the zone closest to the highest oxygen and nutrient supply, but they are also closest to portal venous blood-borne toxins and antigens. Which liver zone is this?
Show answer and explanation
Answer: A. Liver zone 1. Liver acinus is divided into 3 zones based on distance from portal triad and oxygen gradient. Zone 1 (periportal) is closest to the portal triad with HIGHEST oxygen and nutrients but is first to encounter portal blood-borne toxins and antigens. Vulnerable to viral hepatitis (especially HBV), ingested toxins (phosphorus poisoning), and primary biliary cholangitis. Hepatic regeneration is most active here.
Why the other choices are tempting
- B. Zone 2 (midzonal) is classically injured in yellow fever (with apoptotic Councilman bodies).
- C. Zone 3 (centrilobular) is closest to central vein, has LOWEST oxygen and HIGHEST CYP450 activity; vulnerable to acetaminophen toxicity, alcoholic hepatitis, ischemic injury (centrilobular necrosis).
- D. Bile duct epithelium is in portal triads.
- E. Kupffer cells are sinusoidal macrophages throughout the lobule.
Flashcards
Tap a card to flip it.
What clue supports Liver zone 1 vulnerability?
Choose Liver zone 1 vulnerability when the stem gives this pattern: Liver zone 1 near portal triad receives most oxygen and nutrients and is vulnerable to viral hepatitis and phosphorus poisoning patterns.
What clue supports Liver zone 3 vulnerability?
Choose Liver zone 3 vulnerability when the stem gives this contrasting pattern: Liver zone 3 near central vein has least oxygen and highest CYP activity, vulnerable to ischemia, acetaminophen toxicity, and alcohol injury.
Quick answers
What is the fastest way to tell Liver zone 1 vulnerability from Liver zone 2 and zone 3 vulnerability?
Zone 1 is periportal and oxygen-rich; zone 2 is yellow fever; zone 3 is centrilobular, low oxygen, and CYP-toxic.
What is the key clue for Liver zone 1 vulnerability?
Liver zone 1 near portal triad receives most oxygen and nutrients and is vulnerable to viral hepatitis and phosphorus poisoning patterns.
What is the key clue for Liver zone 2 and zone 3 vulnerability?
Zone 2 midzonal injury is classic for yellow fever; zone 3 is centrilobular, high CYP450/low oxygen, and vulnerable to acetaminophen toxicity and ischemia.
What is the common trap with Liver zone 1 vulnerability vs Liver zone 2 and zone 3 vulnerability?
Zone 1 is periportal oxygen-rich; zone 3 is centrilobular low oxygen and high CYP toxin metabolism.