w/c 10-Mar-14

Question 1

Normal signalment of dogs with struvite stones

Answer 1

Magnesium ammonium phosphate. 85% are female. Most dogs have concurrent UTI and urease producing bacteria = ALKALI pH urine

Question 2

pH of urine of dog with struvite

Answer 2

Normally alkaline due to urease of concurrent UTI

Question 3

Treatment of Struvite stones

Answer 3

Treat underlying UTI for 3-4 weeks. Reduce urinary magnesium, ammonium and phosphate (is supersaturated!)
Maintain pH at 6.4
S.G. <1.015

Question 4

Danger associated with Struvite preventative diets

Answer 4

May result in Calcium Oxalate stones forming

Question 5

Which type of stones cannot be dissolved?

Answer 5

Calcium Oxalate stones cannot be dissolved. Treatment involves Urohydropropulsion or Surgery

Question 6

Calcium oxalate recurrence rate within 3 years

Answer 6

60% Recurrence rate within 3 years

Question 7

Signalment for Ammonium urate stones?

Answer 7

Dalamations (due to reduced conversion of uric acid to allantoin)
Hepatic dysfunction - porto-systemic shunt. Increased excretion of ammonia and urea.

Question 8

Which drug is used to treat/prevent Ammonium urate stones?

Answer 8

Allopurinol competitively inhibits Xanthine oxidase.

Reduce purines

Question 9

Urine pH for Struvite stones

Answer 9

Alkaline

Question 10

Urine pH for Calcium Oxalate stones

Answer 10

Acidic to neutral.

Question 11

How should the diet be changed if Calcium Oxalate stones are suspected?

Answer 11

pH changes are not as important with this type of cystal.
Do not restrict phosphorous / feed low protein or renal diet. This results in increased calcium excretion.
Feeding canned diets (>85% water) can be useful. or dry diets with increased salt to increase water intake