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Clinical Symptom🐕 Dogs🐈 Catsgastrointestinalhematologic immune

Icterus (Jaundice)

🗣️ Pronounced:IK-ter-us / JON-dis
In One Sentence (Plain English)

A yellow discoloration of the skin, sclera (whites of the eyes), gums, and mucous membranes caused by high levels of bilirubin in the blood.

Editorial Status: Verified from peer-reviewed veterinary sources (v1.0)
Updated: 2026-01-15

💬 In Plain English

Icterus (commonly called jaundice) happens when a yellow pigment called bilirubin builds up in the bloodstream and deposits in tissues. Bilirubin is a normal byproduct of recycling old red blood cells, which the liver normally processes and excretes into bile. In pets, jaundice is easiest to spot on the whites of the eyes (sclera), inner ear flaps, gums, and belly skin. Icterus is caused by one of three mechanisms: massive red blood cell destruction (pre-hepatic), liver failure (hepatic), or a blocked bile duct (post-hepatic).

🔬 Clinical & Technical Depth

For Vets & Technicians

Formal Clinical Definition

Hyperbilirubinemia leading to yellow pigmentation of tissues. Pre-hepatic causes involve rapid intravascular or extravascular hemolysis (e.g., IMHA). Hepatic causes involve hepatocellular dysfunction (e.g., hepatic lipidosis, hepatitis). Post-hepatic causes involve biliary tree obstruction (e.g., pancreatitis, cholelithiasis).

Why Veterinarians Use It

Veterinarians identify icterus as a key physical finding that instantly narrows the differential diagnosis to the liver, gallbladder, or hemolytic blood disorders.

Clinical Context Encountered

Seen in cats with hepatic lipidosis (fatty liver) following a few days of not eating, dogs with immune-mediated hemolytic anemia (IMHA), or severe acute pancreatitis.

Clinical Reference Guide (Clinical Symptom)

Urgency Level

🚨 Red Flag Warnings (When to Contact an Emergency Vet)
  • •Icterus is never normal and indicates serious underlying disease. In cats, yellow skin following appetite loss indicates life-threatening hepatic lipidosis that requires urgent nutritional tube intervention.

❓ Questions to Ask Your Veterinarian

Take these actionable questions with you to your next clinic visit or appointment:

  • 1Is the jaundice classified as pre-hepatic (hemolytic anemia), hepatic (liver disease), or post-hepatic (gallbladder blockage)?
  • 2What was the total bilirubin level on the chemistry panel?
  • 3What is my pet’s hematocrit or PCV (packed cell volume) to check for severe anemia?
  • 4Does abdominal ultrasound show gallstones, an enlarged gallbladder, or pancreatitis compressing the bile duct?

Academic & Clinical References