Canine Calcium Oxalate

The contour of these small to medium sized (usually 1 to 7 mm), radio-opaque stones can be irregular, spiked, smooth or combinations.

Calcium oxalate (CaOx) is a common and difficult stone to prevent because factors responsible for formation are incompletely understood. It is accepted that crystal growth and possibly initial crystal formation are at least partly a reflection of urine supersaturation. Therefore, controlling risk factors promoting urine CaOx supersaturation (e.g. hypercalciuria, hyperoxaluria, hyperaciduria, hypocitraturia, and highly concentrated urine) should minimize urolith recurrence.

• Serum calcium. Investigate causes for hypercalcemia, when present. • Genetic test for Hereditary Calcium Oxalate Urolithiasis Type 1 in at risk breeds (e.g. English Bulldogs, Boston Terriers, and American Staffordshire Terriers). z.umn.edu/caninegenetics

• Correct hypercalcemia based on cause (e.g. parathyroidectomy for primary hyperparathyroidism). • Potassium citrate if urine pH is consistently less than 6.5 (starting dose: 75mg/kg q12-24 hr). • Hydrochlorothiazide with highly recurrent stones (2mg/kg q12-24 hr).

• Lower sodium foods that do not overly acidify urine (e.g. c/d multicare, u/d, g/d, i/d low fat, others). If needed, feed canned therapeutic foods or add water to achieve a urine specific gravity less than 1.020.

Urinalysis every 3 to 6 months to adjust pH to 6.5 to 8.0, and urine specific gravity to 1.020 and lower. Medical imaging every 6 to 12 months to detect recurrent stones when small to permit their easy removal without surgery.

We advise reviewing manufacturer's literature regarding selected therapeutic foods to determine indications and contraindications. For pets with multiple health concerns,we suggest that the selection of diet should take into consideration all health needs of the pet.

Canine Calcium Oxalate