Icterus in Cats
Icterus (or jaundice) is a yellow discoloration of the gums and tissues due to a higher concentration of bilirubin, a bile pigment formed as a result of the normal breakdown of hemoglobin present in red blood cells (RBCs). Hemoglobin is normally found in RBCs and serves the very important function of carrying oxygen to tissues. In cases of increased destruction of RBCs, an excess amount of bilirubin is accumulated in the tisses which which cannot be eliminated at normal rates. Higher concentrations of bilirubin may also be found in cases where normal excretion of bilirubin is blocked due to some disease. All breeds of cats can be affected by jaundice.
Symptoms and Types
- Abdominal pain
- Loss of appetite (anorexia)
- Yellowish discoloration of the skin
- Change in color of urine and feces (orange colored)
- Increased frequency (polyuria) and volume of urine
- Increased thirst (polydipsia) and consumption of water
- Mental confusion in advanced cases
- Weight loss
- Bleeding (especially in cats with advanced liver disease)
- Diseases, toxins, drugs leading to increased destruction of RBCs
- Incompatible blood transfusion
- Collection of large volume of blood inside body cavity
- Inflammation of liver (hepatitis)
- Accumulation of excess fat in liver (hepatic lipidosis)
- Massive damage to liver tissue (e.g., due to toxins)
- Interference with secretion of bilirubin due to any disease and condition
Your cat’s veterinarian will take a detailed history from you and perform a complete physical examination on your cat. Routine laboratory tests including: complete blood count, biochemistry profile and urinalysis will be conducted. These tests will reveal very valuable information for the initial diagnosis. Complete blood count tests may reveal changes in RBC structures, changes pertaining to underlying infections like severe anemia, blood parasites, and abnormally low levels of platelets (cells responsible for blood clotting). The biochemistry profile, meanwhile, may reveal abnormally high levels of liver enzymes pertaining to liver injury. And urinalysis will show abnormally high levels of bilirubin in urine.
There are more specific tests available for further diagnosis, including underlying causes. Radiographic studies will help in the determination of structure and size of the liver, which is the central organ of importance in this disease. These X-rays often find the liver enlarged, reveal the presence of a mass or tumor, the enlargement of the spleen in some cases, and foreign bodies. Thoracic X-rays may reveal metastasis if a tumor is the cause. Ultrasound will also be performed, enabling your veterinarian to evaluate the liver structure in detail, helping to distinguish liver disease from an obstruction of biliary tract, as well as differentiating a tumor from a mechanical obstruction.
Additionally, the veterinarian may decide to take a sample of liver tissue with the aid of ultrasound for a more detailed evaluation. Liver tissue samples may be taken through a needle or during surgery, which may be performed for confirmatory diagnosis and treatment.