Cirrhosis Pathology

From normal lobule to nodule

The healthy liver organizes hepatocytes into hexagonal lobules — blood arrives at portal triads (portal vein, hepatic artery, bile duct), flows through sinusoids over plates of hepatocytes, and drains into central veins. Chronic injury — whether alcohol, viral, autoimmune, metabolic, or biliary — kills hepatocytes faster than they can regenerate. Hepatic stellate cells in the space of Disse, normally quiescent vitamin-A storage cells, are activated by inflammatory signals (TGF-β, PDGF). They transdifferentiate into myofibroblasts and lay down type I collagen. Fibrosis progresses through stages F0 (no fibrosis) → F1 (portal) → F2 (periportal) → F3 (bridging septa) → F4 (cirrhosis — diffuse fibrous septa enclosing regenerative nodules). Once at F4, the architecture is permanently distorted — sinusoids capillarized, intrahepatic resistance high.

Portal hypertension — the driver of decompensation

Portal venous pressure rises as sinusoids are obliterated. The hepatic venous pressure gradient (HVPG) — wedge minus free hepatic vein pressure — quantifies it. Normal HVPG is 1–5 mmHg. >5 is portal hypertension. >10 mmHg is "clinically significant" — varices, ascites, and decompensation events become likely. >12 mmHg predicts variceal bleeding. >16 increases mortality. The body grows collateral veins to bypass the obstruction: lower esophageal and gastric (varices), umbilical (caput medusae), retroperitoneal, and rectal (hemorrhoids). The splanchnic vasodilation also drives an "effective arterial hypovolemia" that activates RAAS, sympathetic, and ADH — explaining the avid sodium retention behind ascites and the renal vasoconstriction behind hepatorenal syndrome.

Worked clinical example — the alcoholic with first decompensation

A 54-year-old man with 25-year heavy alcohol use presents with a tense abdomen and confusion. Exam: BP 102/64, HR 96, T 38.0, asterixis, tense ascites, splenomegaly, palmar erythema, spider angiomas. Labs: AST 78 / ALT 42 (AST:ALT ratio >2, classic alcoholic pattern), bilirubin 4.8, INR 1.9, creatinine 1.4 (baseline 0.9), albumin 2.6, Na 128, platelets 84k. Diagnostic paracentesis: 1100 PMNs/mm³, SAAG 1.7. The picture: alcohol-related cirrhosis with three simultaneous decompensations — ascites with spontaneous bacterial peritonitis (PMN >250), hepatic encephalopathy West Haven II, and probable hepatorenal physiology. MELD-Na ~25 (sick). Plan: IV cefotaxime + albumin 1.5 g/kg day 1, 1 g/kg day 3 (improves AKI survival in SBP), lactulose to 2–3 soft stools/day plus rifaximin 550 mg BID, alcohol cessation (and treat withdrawal — benzos with caution given encephalopathy risk), thiamine before glucose, screen for HCC with ultrasound and AFP, refer to transplant after 3–6 months sobriety. The clock is short: decompensated median survival untransplanted ~2 years.

The four decompensations

1. Variceal hemorrhage. Dilated submucosal veins in the lower esophagus or gastric fundus. ~50% of cirrhotics develop varices; ~30% with varices will bleed. Per-bleed mortality 15–20%. Screen with EGD at diagnosis. Prophylaxis: non-selective β-blocker (propranolol, carvedilol) or endoscopic variceal ligation. Active bleed: IV octreotide, IV ceftriaxone (improves survival), urgent EGD banding. TIPS for refractory.
2. Ascites. Fluid in the peritoneal cavity from portal hypertension and splanchnic vasodilation. Diagnostic tap every new ascites — SAAG ≥1.1 = portal hypertensive; cell count for SBP (PMN >250). Treatment: salt restriction, spironolactone + furosemide 100:40, large-volume paracentesis with albumin for refractory.
3. Hepatic encephalopathy. Cognitive dysfunction from gut-derived neurotoxins (ammonia and others) bypassing the failing liver. Triggers: GI bleed, infection, dehydration, hypokalemia, constipation, sedatives, dietary protein. Treatment: lactulose, rifaximin. Find and reverse the precipitant.
4. Hepatorenal syndrome (HRS). Functional acute kidney injury from intense renal vasoconstriction in advanced cirrhosis. Type 1 (HRS-AKI): rapid creatinine rise, <2 weeks; type 2: slower, often with refractory ascites. Treatment: albumin + vasoconstrictors — terlipressin (CONFIRM trial 2021; FDA-approved 2022) is now first-line where available, norepinephrine in ICU, midodrine + octreotide. Definitive: transplant.

Hepatocellular carcinoma — the looming sequel

Cirrhosis carries an annual HCC incidence of 3–5%, roughly 30× the baseline population rate. HBV is uniquely oncogenic — viral DNA integration drives HCC even without cirrhosis; surveillance starts on first HBV diagnosis if family history, African origin, or coinfection. For other cirrhotics, AASLD recommends ultrasound every 6 months ± AFP. Suspicious findings → multiphase CT or MRI (LI-RADS scoring). Curative options for early HCC: resection (preserved function, no portal HTN), liver transplant (within Milan: 1 lesion ≤5 cm or up to 3 lesions ≤3 cm), local ablation (RFA, microwave). Palliative: TACE, Y-90 radioembolization, systemic therapy (atezolizumab + bevacizumab now standard).

Compensated vs decompensated cirrhosis

Two clinical stages, very different prognoses

Feature	Compensated	Decompensated
Definition	Histologic cirrhosis without major complications	Any of: variceal bleed, ascites, encephalopathy, HRS, jaundice
HVPG	5–10 mmHg	>10–12 mmHg
Median survival	~10 years	~2 years untransplanted
Bilirubin	Usually normal	Often elevated
INR / Albumin	Preserved	INR rising, albumin falling
Platelets	Mild thrombocytopenia (splenic sequestration)	Often <100k
Child-Pugh	A (5–6 points)	B (7–9), C (10–15)
Transplant indication	HCC within Milan criteria	MELD-Na ≥15 generally
HCC screening	q6 mo ultrasound ± AFP	q6 mo (continues)

Common misconceptions

• "Normal LFTs rule out cirrhosis." Late cirrhosis often has near-normal ALT — fewer hepatocytes left to leak enzymes. Suspicious findings (low platelets, splenomegaly, AST:ALT >1, low albumin) matter more than ALT.
• "Cirrhosis is irreversible." Mostly true once fully established, but partial reversal occurs with sustained removal of injury — HBV suppression, HCV cure, alcohol abstinence, weight loss in MASLD. Fibrosis stages can step back; outcomes improve.
• "Restrict protein in encephalopathy." Old teaching. Current evidence supports normal protein intake (1.2–1.5 g/kg/day) — malnutrition is its own driver of complications.
• "Diuretics first for new ascites." Tap first. Every new ascites needs a diagnostic paracentesis to rule out SBP and confirm portal hypertensive etiology with SAAG.
• "Variceal bleed is volume — give 4 units." Over-resuscitation (Hb target above ~7–8) raises portal pressure and worsens bleeding. Restrictive transfusion strategy is standard.
• "Acetaminophen is contraindicated in cirrhosis." Up to 2 g/day is safer than NSAIDs (which precipitate AKI/HRS and bleeding). NSAIDs are the drugs to avoid.