Q: I have a 2-year-old male cat, Prisspot. My cat was diagnosed with a portosystemic shunt in May of this year. He is currently being managed through diet and medicine because I cannot afford the cost of the surgery. He takes ¼ tablet of metronidazole in the mornings, 1 ml of lactulose twice a day and was prescribed Hill’s Prescription Diet L/D and K/D cat food.
He will not eat the cat food very well. I have called the vet that diagnosed him about this on several occasions about what else I could feed him, but did not receive a clear answer other than he has to be on a low protein diet. What can I feed him? I am very worried about him because he is losing weight.
A: A portosystemic shunt is a condition in which a cat’s portal vein, which carries blood from the intestinal tract, gets diverted around the liver rather than through the liver. The liver never gets to detoxify this blood. Toxins from the intestinal tract get into the bloodstream where they can cause neurological and behavioral problems.
A surgical procedure in which the blood flow through the shunting vessel is slowly closed off, diverting the blood back through the liver, is the ideal treatment, but as you noted, this needs to be done by an experience surgeon at a referral center and is very costly. Because the toxins are mainly derived from protein, feeding a diet low in protein helps reduce the toxin level.
The Hill’s company makes two low-protein prescription diets, K/D and L/D. Most cats find these diets palatable and will eat them, although some cats do not like these diets and will not eat them. Fortunately, other pet food manufacturers produce these low-protein diets. The Iams Company makes a renal diet. Purina makes one called NF. The Royal Canin Company makes one called Renal LP.
We carry all of these diets at my cat practice, because cats can be so notoriously fussy. If your cat simply won’t eat a commercially prepared low-protein diet, it is possible to make a homemade cat diet using your own low-protein ingredients at home, however, this has to be done properly, so that the diet is complete and balanced. I recommend this website out of the University of California, Davis, for advice on how to prepare your own home-cooked low-protein diet. Good luck!