Dog & Cat HospitalCalabasas

Patient Education

Liver Disease (Hepatopathy)

The liver has remarkable regenerative capacity — but its quiet way of compensating means disease is often advanced by the time signs appear. Early detection and cause-specific treatment make a meaningful difference.

Liver disease — also called hepatopathy — is not a single condition but an umbrella for many different disorders that impair the liver's ability to filter toxins, produce proteins, metabolize nutrients, and regulate blood clotting. In dogs, the most common forms include chronic hepatitis (inflammatory disease of the liver), steroid hepatopathy (from endogenous or administered corticosteroids), toxic injury, secondary hepatopathy driven by systemic diseases such as Cushing's disease (hyperadrenocorticism) or diabetes, and gallbladder disease. In cats, cholangitis (inflammation of the bile ducts and surrounding liver tissue) is the most common primary liver diagnosis and frequently co-occurs with inflammatory bowel disease and pancreatitis — a triad known in veterinary medicine as "triaditis." Liver tumors, both primary and metastatic, can affect either species. Vascular liver disease — including portosystemic shunts — represents a separate structural category requiring its own workup. At Dog & Cat Hospital Calabasas, Dr. Brian Norman (ACVIM board-certified internal medicine) manages complex hepatic cases, supported by on-site ultrasound, a full in-house laboratory, and image-guided biopsy capability.

Signs & Symptoms

Because the liver compensates quietly until a significant portion is compromised, many pets with liver disease show no signs initially. When signs do develop, they reflect either the liver's failure to detoxify the blood or obstruction of bile flow:

  • Decreased appetite and progressive weight loss
  • Vomiting, sometimes with bile, especially in the morning
  • Increased thirst and urination (polyuria/polydipsia) — the liver helps regulate glucose and blood proteins, and its dysfunction raises urine output
  • Jaundice (icterus) — yellow discoloration of the gums, whites of the eyes (sclera), and inner ear skin; indicates bilirubin accumulation and is always clinically significant
  • Abdominal distension from fluid accumulation (ascites) caused by low blood albumin or portal hypertension
  • Pale or orange-tinged stool and dark, tea-colored urine (bile pigments)
  • Hepatic encephalopathy (HE) — in advanced disease, toxins that the failing liver cannot clear (especially ammonia) accumulate and affect the brain, causing disorientation, head pressing, stumbling, behavioral changes, or seizures
  • Bleeding tendencies — bruising or prolonged bleeding from minor wounds because the liver produces clotting factors

Any pet showing jaundice or signs of hepatic encephalopathy needs same-day evaluation — these indicate severe or rapidly progressing liver failure.

Causes & Risk Factors

Liver disease has a long differential list, which is why identifying the specific cause matters — treatments differ substantially:

  • Chronic hepatitis (dogs): immune-mediated or infectious hepatitis, sometimes breed-associated (Dobermans, Labrador Retrievers, Cocker Spaniels, Standard Poodles have genetic forms); copper-storage hepatopathy is particularly recognized in Bedlington Terriers, Labrador Retrievers, and Dalmatians
  • Cholangitis (cats): inflammation of the biliary tree, either neutrophilic (bacterial) or lymphocytic (immune-mediated); often co-occurs with IBD and pancreatitis
  • Toxic hepatopathy: medications (phenobarbital, NSAIDs, certain antifungals, some supplements), blue-green algae (cyanobacteria), xylitol, and certain mushroom species can cause acute liver failure
  • Secondary / metabolic hepatopathy: Cushing's disease, hypothyroidism, and poorly controlled diabetes all cause secondary liver changes that resolve when the primary disease is treated; vacuolar hepatopathy is the classic histopathologic pattern
  • Gallbladder disease: inspissated (thickened) bile, mucoceles (abnormal gallbladder distension), and cholelithiasis (bile duct stones) impair bile flow and cause secondary liver damage
  • Vascular disease: portosystemic shunts divert blood around the liver, causing HE and liver atrophy; typically congenital in small breeds and Labrador Retrievers, or acquired in dogs with portal hypertension
  • Neoplasia: hepatocellular carcinoma, bile duct carcinoma, lymphoma, and metastatic tumors

Elevated liver enzymes or signs of liver disease in your dog or cat?

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How We Diagnose It

Identifying the cause of liver disease requires layering multiple diagnostic tests — no single test gives the full picture:

  • Serum chemistry panel: liver enzyme activity (ALT, ALP, AST, GGT) reflects ongoing cell damage and biliary obstruction; elevated ALP with normal ALT is typical of steroid hepatopathy; dramatically elevated ALT suggests hepatocellular injury
  • Bilirubin and bile acids: total bilirubin quantifies jaundice; pre- and post-meal bile acids (the bile acids stimulation test) measure functional hepatic capacity and portal vascular anatomy — essential for detecting portosystemic shunting and assessing severity of function loss
  • Complete blood count: anemia, elevated white cells, and abnormal red cell shapes (acanthocytes) each add diagnostic information
  • Coagulation profile: prothrombin time (PT) and partial thromboplastin time (PTT) assess bleeding risk before any biopsy procedure
  • Abdominal ultrasound: evaluates liver echogenicity, size, and architecture; identifies gallbladder disease, dilated bile ducts, vascular abnormalities, and focal masses; guides fine-needle aspirate or biopsy needle placement
  • Liver aspirate or biopsy: cytology from a fine-needle aspirate can identify neoplasia or vacuolar change; tissue biopsy (via ultrasound guidance, laparoscopy, or surgery) provides definitive histopathology — distinguishing hepatitis subtypes, quantifying copper accumulation, and grading fibrosis

Treatment Options

Treatment depends entirely on the underlying cause — which is why reaching a histopathologic diagnosis before committing to long-term therapy is important:

  • Hepatoprotectants: SAMe (S-adenosylmethionine) supports glutathione production and is used broadly as a liver-protective supplement; silybin (milk thistle extract) has antioxidant and anti-inflammatory properties and is well-tolerated in both species; ursodiol improves bile flow and is used in cholangitis and gallbladder disease
  • Antibiotics: neutrophilic cholangitis in cats is treated with antibiotics guided by bile culture when possible; ascending bacterial infection is the suspected mechanism
  • Immunosuppressive therapy: lymphocytic cholangitis in cats and immune-mediated hepatitis in dogs are managed with prednisolone; multi-drug protocols are used in refractory cases
  • Copper chelation and restriction: in copper-storage hepatopathy, a copper-restricted diet combined with d-penicillamine (a chelator) reduces toxic copper accumulation
  • Treating the primary disease: secondary hepatopathy from Cushing's disease, diabetes, or hypothyroidism often fully reverses with successful management of the underlying endocrine condition
  • Supportive care: low-protein diet and lactulose to reduce ammonia production in hepatic encephalopathy; IV fluids and nutritional support during acute decompensation
  • Gallbladder surgery: mucoceles causing obstruction or rupture risk require cholecystectomy (gallbladder removal), performed by our surgical team

When to See Our Team in Calabasas

Elevated liver enzymes found on routine bloodwork — even in a pet with no symptoms — always warrant follow-up to determine their significance and trajectory. Any pet showing jaundice, signs of encephalopathy (confusion, stumbling, head pressing), or abdominal distension needs same-day or emergency evaluation. Cats in the liver disease triad of cholangitis, IBD, and pancreatitis benefit particularly from an internal medicine specialist who can hold all three threads simultaneously. Dr. Norman's combination of diagnostic expertise and on-site ultrasound and biopsy capability means that working up a complex hepatopathy doesn't require travel to a distant specialty center. Book an appointment and let us find out what's behind those elevated liver values.

Frequently Asked Questions

1Are my dog's elevated liver enzymes dangerous?
Elevated liver enzymes are a signal worth investigating, not a diagnosis on their own. Mildly elevated ALT or ALP can reflect anything from a recent fatty meal to early hepatitis; markedly elevated values or a rising trend on repeat testing warrant imaging and possibly biopsy. A single abnormal panel rarely tells the whole story — context and the degree of elevation matter.
2What does it mean if my dog or cat has jaundice?
Jaundice (yellow gums, skin, or whites of the eyes) means bilirubin is accumulating in the blood, which can stem from liver failure, bile duct obstruction, or rapid red blood cell destruction. It is always a significant finding and warrants same-day veterinary evaluation to identify and treat the underlying cause.
3Can liver disease in cats be reversed?
Some forms of feline liver disease are highly treatable — neutrophilic cholangitis often responds well to antibiotics, and secondary hepatopathy resolves when the primary disease is controlled. Lymphocytic cholangitis requires long-term management but is compatible with years of comfortable life. Advanced fibrosis or hepatic failure carries a more guarded prognosis.
4What are the signs of hepatic encephalopathy in dogs?
Hepatic encephalopathy (HE) occurs when the failing liver cannot clear ammonia and other toxins from the blood, which then affect the brain. Signs include disorientation, aimless wandering, head pressing against walls, stumbling, behavioral changes, and in severe cases seizures. HE is a medical emergency requiring immediate stabilization.
5Is a liver biopsy safe for my dog or cat?
Ultrasound-guided liver biopsy is generally safe when clotting function is checked beforehand and the patient is stable enough for the procedure. The risk of significant bleeding is low in patients with adequate platelet counts and normal clotting times. The benefit — knowing the exact type of liver disease to guide long-term treatment — usually far outweighs the procedural risk.
6Can supplements like milk thistle really help my dog's liver?
Silybin (the active component of milk thistle extract) and SAMe (S-adenosylmethionine) have genuine hepatoprotective properties supported by veterinary research and are commonly used alongside primary treatment. They are not a substitute for diagnosing and treating the underlying cause, but they are reasonable adjuncts in most cases of hepatic disease.
7What should my dog with liver disease eat?
Diet recommendations vary by the type and severity of liver disease. Dogs with hepatic encephalopathy benefit from a reduced-protein, highly digestible diet to limit ammonia production. Copper-storage disease requires a copper-restricted diet. Most other forms of hepatopathy do not require severe protein restriction and are better served by a highly digestible, balanced diet. Specific recommendations should come from your veterinarian after diagnosis.
8Can Cushing's disease in dogs cause liver problems?
Yes — Cushing's disease (hyperadrenocorticism) is one of the most common causes of elevated liver enzymes in middle-aged and older dogs. Chronically elevated cortisol causes a vacuolar hepatopathy — a liver that swells with stored glycogen. The liver changes typically resolve significantly once Cushing's disease is diagnosed and treated with appropriate medication.

Related

ServicesInternal MedicineProceduresAbdominal UltrasoundProceduresBiopsy & Fine-Needle AspirateConditionsPortosystemic (Liver) Shunt

Elevated liver enzymes or signs of liver disease in your dog or cat?

Dr. Brian Norman, our on-site ACVIM internal medicine specialist, evaluates complex hepatic cases using in-house bloodwork, abdominal ultrasound, and guided biopsy — without the wait of an outside referral.

Book an Appointment