Questions: Liver Cirrhosis and Portal Hypertension

Question 1

A patient with cirrhosis develops large-volume ascites. Serum albumin is 2.0 g/dL, INR is 2.6, and bilirubin is 5.1 mg/dL. What is the primary mechanism driving the ascites?

• A. Increased portal venous pressure combined with reduced oncotic pressure from hypoalbuminemia
• B. Acute hepatitis causing direct peritoneal inflammation and fluid exudation
• C. Reduced cardiac output leading to systemic fluid retention and edema
• D. Bile duct obstruction causing backpressure into the peritoneal cavity

Answer: (A)

Cirrhotic ascites arises from two converging mechanisms: (1) portal hypertension — fibrous architectural distortion increases sinusoidal resistance, backing up pressure into the portal system and forcing fluid into the peritoneal cavity from splanchnic capillaries; (2) hypoalbuminemia — synthetic failure reduces oncotic pressure, allowing fluid to leak from the intravascular compartment. These are synergistic. Option C describes right heart failure ascites, which has different physical examination findings (jugular venous distension, peripheral edema) and pathophysiology.

Question 2

A patient with cirrhosis from hepatitis C achieves sustained virologic response (SVR) — undetectable HCV RNA — after antiviral therapy. What happens to the cirrhosis?

• A. The cirrhosis resolves completely within 12–18 months as the liver regenerates without ongoing viral injury
• B. The cirrhosis continues to progress because fibrosis becomes self-sustaining once stellate cells are activated
• C. Progression stops and established fibrosis largely persists, though some histological regression may occur over years
• D. The patient converts to acute hepatitis as the immune system mounts a response against residual infected cells

Answer: (C)

Achieving SVR removes the ongoing injury stimulus, arresting progression — this is a major clinical benefit. However, established cirrhotic fibrosis does not simply dissolve. Collagen deposited in fibrous septa degrades slowly, and architectural distortion of the regenerative nodule pattern is not easily reversed. Some degree of fibrosis regression has been documented histologically over years in SVR patients, particularly at earlier fibrosis stages, but clinically significant reversal of advanced cirrhosis is uncommon. The common misconception — that viral clearance 'cures' cirrhosis — is dangerous because it may cause patients and clinicians to reduce surveillance for hepatocellular carcinoma and variceal complications.

Question 3

Hepatic encephalopathy in cirrhosis results primarily from the liver's failure to synthesize adequate clotting factors, which allows microbleeds into brain tissue.

• T. True
• F. False

Answer: False

Hepatic encephalopathy is driven primarily by ammonia accumulation, not coagulopathy. Gut bacteria metabolize amino acids and produce ammonia; the healthy liver converts this to urea (the urea cycle) and prevents it from reaching systemic circulation. In cirrhosis, two mechanisms allow ammonia to bypass this detoxification: (1) portosystemic collaterals (varices) shunt portal blood directly to systemic circulation, bypassing the liver entirely; (2) reduced functional hepatocyte mass impairs the urea cycle. Ammonia that reaches the brain impairs astrocyte function and causes the neurological symptoms of encephalopathy. Coagulopathy is a separate complication of synthetic failure.

Question 4

Portal hypertension can develop in patients with compensated cirrhosis who have no overt symptoms, because portosystemic collaterals partially compensate before decompensation occurs.

• T. True
• F. False

Answer: True

Compensated cirrhosis is defined by the presence of portal hypertension and its structural sequelae (collaterals, splenomegaly) without overt complications (variceal bleeding, ascites, hepatic encephalopathy). The collateral channels that form in response to portal hypertension can handle the diverted flow for years without rupturing or causing clinically apparent disease. This is why surveillance endoscopy to detect varices before bleeding, and regular imaging for hepatocellular carcinoma, are recommended even in patients who feel well. Decompensation often arrives suddenly — variceal hemorrhage carries 20–30% in-hospital mortality — making pre-decompensation identification critical.

Question 5

Explain why the architectural distortion of cirrhosis — rather than simply the loss of individual hepatocytes — is the key driver of portal hypertension.

Model answer: The liver's normal blood flow depends on a low-resistance vascular architecture: portal blood percolates through wide, fenestrated sinusoids lined by hepatocytes in close contact with the blood. In cirrhosis, collagen deposited by activated hepatic stellate cells fills the perisinusoidal space of Disse, replacing the fenestrated endothelium with a dense fibrous matrix (capillarization of the sinusoids). Additionally, regenerative nodules of hepatocytes surrounded by fibrous septa compress and distort the sinusoidal channels. These structural changes dramatically increase hydraulic resistance to blood flow through the liver. Portal pressure rises in proportion to this resistance increase. Even if individual hepatocytes remain viable within nodules, the architectural distortion alone is sufficient to generate portal hypertension.

This distinction matters clinically. A patient could theoretically lose 30% of hepatocytes to acute necrosis and recover full function as remaining cells regenerate in normal architecture. But in cirrhosis, the fibrotic skeleton prevents normal regeneration — cells grow back into nodules surrounded by scarring, not into the functional lobular architecture. This is why liver transplant (replacing the entire architectural unit) is the only definitive therapy: antifibrotic approaches or cell replacement alone cannot reconstruct the spatial organization that function requires.