Dear Dr. John,

My husband and I own three cats that are all in good health. Recently they had their annual exams and two were determined to need dental cleanings and an extraction or two. Bloodwork was done to assess their suitability for anesthesia, and it turned out that one of the cats had a high total bilirubin. What is bilirubin and what does the high value mean? I asked my vet, and he talked about doing something called bile acids and some other diagnostic tests if a recheck in a few weeks’ time did not show a normalization of the increased value. My vet said that all the other bloodwork seemed relatively normal and since my cat showed no sign of being jaundiced then it may have been a fluke finding. Should I be concerned? S.M.

Dear S.M.,

Bilirubin is something that the body makes upon the breakdown or destruction of red blood cells. Red blood cells in cats have a life of about two to three months before they stop functioning and are broken down for elimination by the body as a course of normal action. It is found in bile which is produced in the liver to help in the digestion of food.

The high value can have various meanings. It is true that what was found might have been a fluke finding that might correct itself, given the lack of other significant changes in the bloodwork. Moderate increases in total bilirubin in cats may have no explanation. The absence of your cat being jaundiced might also suggest an incidental finding. However, it could also be a clue that something is wrong or is developing and a possible problem would be localized to the liver, the gallbladder, or something causing increased breakdown of red blood cells known as hemolysis.

Further diagnostics might include bile acids, abdominal ultrasound, biopsies, and more. I would hold off on being concerned until follow up bloodwork is done and then your veterinarian can instruct you further as needed. Good luck.

Dr. John de Jong owns and operates the Boston Mobile Veterinary Clinic. He can be reached at 781-899-9994.