A diagnosis of fatty liver syndrome is based on a history, physical examination, and blood tests that reveal liver disease. Usually, the history and exam will have revealed that the cat had been obese and then suddenly stopped eating. Cats with fatty liver syndrome often appear jaundiced, meaning that they have a yellowish color to their gums, skin, and the whites of their eyes.
A complete blood count, or CBC, is performed to rule out other causes of jaundice, such as abnormal destruction of the red blood cells, which results in severe anemia. A serum chemistry panel will show abnormalities in the liver enzymes, and may help to identify other concurrent diseases that may have caused or aggravated the cat's fatty liver syndrome.
The only way to diagnose hepatic lipidosis definitively is to examine a sample of the liver. This sample can be obtained using a needle while the cat is sedated mildly. The cells obtained are stained and examined under the microscope, a process called cytology. An even more accurate method is a liver biopsy, which is a larger sample of the liver that is obtained surgically or with an ultrasound-guided biopsy instrument. This is a more invasive procedure, and has a higher potential for complications. But, it is more accurate because of the larger sample of tissue obtained. Before a liver sample is taken, however, a clotting profile must be conducted to ensure that the cat does not bleed excessively from the procedure.
