What can I do for my dog that has oxalate stones?

Posted in: 

Q: My 10-year-old male schnauzer, Rudy, has been diagnosed with oxalate crystals. (He had bladder surgery 4 weeks ago.) We have started to feed him raw food with added fruits and vegetables. Is this the best diet for him? Is it necessary for him to have additional potassium in his diet?

A: I am sorry to hear this about Rudy. The basic manner in which we address oxalate urolithiasis (stones) is to avoid calcium supplements and foods high in oxalate. This is accompanied by feeding reduced protein diets which promote diuresis (urine flow) and formation of an alkaline urine. For example, Hill's Pet Nutrition u/d or w/d, Royal Canin UrinarySO, or CNM NF-Formula. If an alkaline urine can't be established by diet alone, the addition of potassium citrate is indicated (75mg/lb by mouth every 12 hours, adjusted to increase urine pH to 6.5-7.0).

There's no benefit to a raw diet as compared to a commercial or home-cooked diet when addressing oxalate urolithiasis. Dogs don't have a particular requirement for fruits or vegetables, but these can be given if Rudy prefers them. You'll need to be careful, however, to avoid those fruits and vegetables high in calcium. These can be found by searching "calcium in fruits/vegetables" online.

We generally avoid raw food diets because of their risk of bacterial pathogens to our patients and owners. Salmonella, e.coli, and campylobacter have been found in too many studies for my comfort. Most important, it's tricky to formulate a diet specifically for dogs such as Rudy, and I'd prefer to rely on a prescription diet produced by a major manufacturer who has worked with vets extensively such as those mentioned above.

Regular monitoring is very important for these dogs. A repeat urinalysis every 2 weeks, starting 2 weeks after removal of stones and initiation of dietary changes until pH is between 6.5-7.0, specific gravity is between 1.010-1.020 (quite dilute!), and no calcium oxalate crystals are found. Repeat abdominal radiographs and a urinalysis every 3-6 months thereafter to evaluate for recurrence of uroliths. If calcium oxalate crystalluria persists despite prior measures, the diuretic hydrochlorothiazide (2-4mg/kg by mouth every 12 hours) or vitamin B6 (2mg/kg) by mouth every 12 hours can be added. Avoid supplementation of vitamins C and D.

-- Answer from Dr. Michael Salkin, a veterinarian on JustAnswer.

Daily Answer is excerpted from the JustAnswer archives and features information provided by a Expert on JustAnswer.

Follow JustAnswer on Twitter or like us on Facebook to get useful daily updates.