Hepatic cirrhosis represents the irreversible end-stage of chronic hepatitis, characterized by diffuse fibrosis, regenerative nodules, and architectural distortion.
Overview and Clinical Importance
Hepatic cirrhosis represents the irreversible end-stage of chronic hepatitis, characterized by diffuse fibrosis, regenerative nodules, and architectural distortion. According to the WSAVA, cirrhosis is the histological endpoint of progressive hepatic fibrosis where normal lobular architecture is replaced by abnormal nodular regeneration surrounded by fibrous septa.
Understanding cirrhosis is essential for the NAVLE because it tests your ability to recognize breed predispositions, interpret imaging and laboratory findings, manage complications including portal hypertension and hepatic encephalopathy, and provide appropriate prognostic information.
| Stage |
Pathological Events |
| 1. Hepatocyte Injury |
Ongoing hepatocyte apoptosis and necrosis from copper toxicity, immune-mediated injury, drugs, or idiopathic causes releases inflammatory mediators |
| 2. Stellate Cell Activation |
Hepatic stellate cells (HSCs) transform from quiescent vitamin A-storing cells to activated myofibroblasts that produce extracellular matrix (ECM) |
| 3. ECM Accumulation |
Total collagen content increases 3- to 10-fold; collagen types I and III predominate with cross-linking modifications |
| 4. Architectural Disruption |
Bridging fibrosis (portal-portal or portal-central) develops, followed by nodule formation, portal hypertension, and acquired portosystemic shunts (APSS) |
Definition and Pathophysiology
WSAVA Definition
Cirrhosis is the histological endpoint of chronic hepatitis characterized by:
- Diffuse fibrosis: Extensive collagen deposition throughout the liver
- Regenerative nodules: Micro- or macro-nodular hepatocyte regeneration
- Architectural distortion: Loss of normal lobular organization
- Irreversibility: The point of no return in chronic liver disease progression
Pathophysiology of Fibrosis Progression
| Etiology |
Key Features |
| Copper-Associated Hepatopathy |
Most common identifiable cause (36% of CH cases); results from genetic mutations affecting copper metabolism; initially centrilobular accumulation progressing to bridging fibrosis |
| Drug-Induced Hepatopathy |
Phenobarbital, primidone, phenytoin, lomustine; may cause direct toxicity or alter xenobiotic metabolism |
| Idiopathic/Immune-Mediated |
Greater than 60% of CH cases have no identifiable cause; characterized by mononuclear cell infiltrate and self-perpetuating inflammation |
| Lobular Dissecting Hepatitis (LDH) |
Severe variant in young dogs; fibrosis dissects individual hepatocytes; rapid progression; over 80% present with ascites |
Etiology and Breed Predispositions
Primary Etiologies
Breed Predispositions and Genetic Mutations
High-YieldOn the NAVLE, when you see a Bedlington Terrier with liver disease, always think copper toxicosis FIRST. Bedlingtons have the highest copper concentrations (greater than 3,000 ppm) and a well-characterized genetic mutation (COMMD1 deletion).
| Breed |
Genetic Mutation |
Copper (ppm) |
Key Features |
| Bedlington Terrier |
COMMD1 deletion (exon 2); also ATP7B variants |
Greater than 3,000 (can exceed 10,000) |
Autosomal recessive; hemolytic crisis possible; genetic testing available |
| Labrador Retriever |
ATP7B mutation (Wilson disease gene) |
Typically 400-2,000 |
Female predisposition; mean age 6-7 years |
| Doberman Pinscher |
ATP7B variant plus immune component |
750-2,000 |
Female predisposition (4-7 yrs) |
| West Highland White Terrier |
Suspected copper transporter defect |
Variable (400-2,000) |
May have concurrent idiopathic CH |
| Cocker Spaniel |
Unknown; possible multifactorial |
Variable |
High incidence of APSS and ascites |
Clinical Signs and Physical Examination
| Clinical Sign |
Frequency |
Pathophysiology |
| Anorexia and Lethargy |
Greater than 50% |
Hepatic dysfunction; accumulation of toxins |
| Vomiting |
~33% |
GI congestion from portal hypertension |
| Ascites |
~33% (80% in LDH) |
Portal hypertension; hypoalbuminemia |
| Jaundice (Icterus) |
~33% |
Impaired bilirubin conjugation and excretion |
| Hepatic Encephalopathy (HE) |
6-7% |
APSS; decreased ammonia clearance |
| GI Bleeding (Melena) |
6-7% |
Coagulopathy; GI ulceration |
Complications of Cirrhosis
Hepatic Encephalopathy (HE) Staging
Acquired Portosystemic Shunts (APSS)
APSS develop as collateral circulation in response to sustained portal hypertension. Unlike congenital shunts, APSS are multiple tortuous vessels typically found near the left kidney at the level of the aorta and caudal vena cava.
NAVLE TipDistinguish APSS from congenital PSS: Congenital shunts are SINGLE anomalous vessels in YOUNG dogs (less than 2 years), while APSS are MULTIPLE tortuous vessels in OLDER dogs with known chronic liver disease.
| Stage |
Clinical Signs |
| Stage 1 |
Subtle behavioral changes; decreased alertness; mild disorientation |
| Stage 2 |
Ataxia; head pressing; circling; blindness (amaurosis); disorientation |
| Stage 3 |
Severe disorientation; stupor; ptyalism (hypersalivation); aggression |
| Stage 4 |
Coma; seizures; death |
Diagnostic Approach
Laboratory Findings
Diagnostic Imaging - Ultrasonography
High-YieldNAVLE TRAP: A normal ultrasound does NOT rule out chronic hepatitis or early cirrhosis! Studies show 14-57% of dogs with confirmed chronic hepatitis have normal liver size on ultrasound.
| Parameter |
Finding |
Clinical Significance |
| ALT |
Normal to mildly elevated |
NAVLE TRAP: Few hepatocytes remain to leak enzymes |
| ALP |
Often elevated |
Cholestasis; biliary hyperplasia |
| Total Bilirubin |
Elevated |
Poor prognostic indicator |
| Albumin |
Decreased |
Poor prognostic indicator; contributes to ascites |
| Bile Acids |
Markedly elevated |
Sensitive indicator of hepatic dysfunction |
| PT/aPTT |
Prolonged |
Poor prognostic indicator |
Treatment and Management
Important: Cirrhosis is irreversible. Treatment is supportive.
Hepatoprotective Therapy
Copper Chelation Therapy
Ascites Management
NAVLE TipSpironolactone is FIRST-LINE for hepatic ascites because it directly antagonizes aldosterone-mediated sodium retention. It also preserves potassium, which is important because hypokalemia can precipitate HE.
Hepatic Encephalopathy Management
Critical Contraindications
Glucocorticoids are CONTRAINDICATED in cirrhosis with:
- Uncontrolled HE: Steroids increase protein catabolism and ammonia
- Refractory ascites: Steroids promote sodium and water retention
- GI ulceration: Steroids impair mucosal healing
| Finding |
Description |
| Hyperechoic Parenchyma |
"Bright liver" - increased echogenicity due to fibrosis |
| Microhepatica |
Decreased liver size from fibrotic contraction |
| Irregular/Nodular Margins |
"Lumpy-bumpy" appearance from regenerative nodules |
| APSS (Color Doppler) |
Multiple tortuous low-flow vessels near left kidney |
Prognosis
Prognosis for cirrhosis is guarded to poor.
High-YieldAscites is the most significant negative prognostic indicator. Dogs with ascites have median survival of only 0.75 months (22.5 days) compared to 24.3 months without ascites.
| Drug |
Dose |
Mechanism |
| Ursodiol (UDCA) |
10-15 mg/kg PO q24h |
Choleretic; anti-inflammatory; cytoprotective |
| SAMe |
20-40 mg/kg PO q24h |
Glutathione precursor; antioxidant; give on empty stomach |
| Vitamin E |
10-15 IU/kg PO q24h |
Antioxidant; membrane stabilization |
| Drug |
Dose |
Notes |
| D-Penicillamine |
10-15 mg/kg PO q12h |
First-line copper chelator; give on empty stomach; GI side effects common |
| Trientine |
10-15 mg/kg PO q12h |
Alternative; better tolerated; more expensive |
| Zinc Acetate |
5-10 mg/kg elemental zinc PO q12h |
Maintenance therapy; blocks intestinal copper absorption |
| Treatment |
Dose |
Notes |
| Spironolactone (FIRST-LINE) |
1-2 mg/kg PO q12h |
Aldosterone antagonist; potassium-sparing; preferred first-line |
| Furosemide (Add-on) |
1-2 mg/kg PO q12-24h |
Add if spironolactone alone inadequate |
| Treatment |
Dose |
Mechanism |
| Lactulose (GOLD STANDARD) |
0.5 mL/kg PO q8-12h |
Acidifies colon trapping ammonia as NH4+; titrate to 2-3 soft stools/day |
| Metronidazole |
7.5 mg/kg PO q12h |
Reduces ammonia-producing gut bacteria; use lower dose due to hepatic metabolism |
| Condition |
Median Survival |
| Chronic hepatitis (all stages, treated) |
561 days (~18.7 months) |
| Biopsy-proven cirrhosis |
23 days |
| Cirrhosis WITH ascites |
22.5 days (~0.75 months) |
| Chronic hepatitis WITHOUT ascites |
24.3 months |