Urolithiasis SA (Byron) (Parts 1 & 2)

Question 1

Calculi (or stones) in the urinary tract

Answer 1

Urolithiasis

Question 2

(T/F) The lower the urine concentration (specific gravity), the more likely crystals are to form

Answer 2

False, the higher the urine conc.

Question 3

(T/F) The lower the temperature of the urine, the more likely crystals are to form

Answer 3

True

Question 4

(T/F) The lower the concentration of inhibitor substances, the more likely crystals are to form

Answer 4

True

Question 5

(T/F) The lower the excretion of calculogenic substances, the more likely crystals are to form

Answer 5

False, the higher the excretion

Question 6

(T/F) pH has an impact on the formation of ALL crystals

Answer 6

False, pH can have an impact on the formation of SOME BUT NOT ALL crystals

Question 7

What stone is extremely sensitive to the pH of the solution?

Answer 7

Struvites, magnesium ammonium phosphate
- in high pH (basic) they are going to precipitate out
- at low pH (acidic) they go back to the solution

Question 8

What is the MOST common stone in dogs?

Answer 8

Struvite

Question 9

What is the MOST common stone in cats?

Answer 9

Calcium Oxalate

Question 10

On what stone does the pH have no effect?

Answer 10

Calcium Oxalate

Question 11

(T/F) Diet can be beneficial for an animal with Calcium Oxalate

Answer 11

False, no diet will prevent Calcium Oxalate from reforming if they already formed once

Question 12

List the reasons when Crystals are a Problem:

Answer 12

• If seen in a patient who is a known stone-former
• Patient with lower urinary tract signs
• Male cat with a history of plug formation/obstruction
• Persistent, significant crystalluria noted
• Urate and cystine crystals

Question 13

Predisposing Factors to stone formation:
- Primarily dogs, Staph spp., struvites
- Cystine, calcium oxalate
- Urate, calcium oxalate
- May predispose, but not a disease in itself

Answer 13

• Infection
• Tubular defects
• Metabolic defects
• Crystalluria

Question 14

What is the key to diagnosing stones in a patient?

Answer 14

Radiographs

Question 15

In dogs ________ and ________ are the most radiopaque, and then cystine and urate (may not be very well visible)

Answer 15

struvites, calcium oxalates

Question 16

In cats ________ are more radiopaque than struvites

Answer 16

Calcium oxalates

Question 17

coffin shape crystal

Answer 17

struvite

Question 18

In a cat, struvites occur in the ___________ in sterile urine

Answer 18

bladder

Question 19

(T/F) 50% of stones in dogs are associated with UTI from Staph spp. and Proteus

Answer 19

True

Question 20

For what stone, do they belive, there is a genetic component?

Answer 20

Calcium Oxalate

Question 21

__________ urinary citrate (and Mg and pyrophosphate) can combine with calcium and oxalic acid (soluble) and reduce CaOx (insoluble) production

Answer 21

increased

Question 22

Hypercalcemia can predispose to:

Answer 22

Hypercaliuria

Question 23

Oxalate can be absorbed from the:

Answer 23

GI tract

Question 24

_____________ deficiency can increase urinary oxalate levels

Answer 24

Vitamin B6

Question 25

(T/F) Dissolution for calcium oxalate is effective

Answer 25

False, dissolution is NOT effective and must be physically removed

Question 26

What is the end product of vitamin C?

Answer 26

Oxalate

Question 27

What stone is the following describing? - Rare in cats - Frequently recur - Look for hepatic dysfunction, although not always present (ammonia urate circulating)

Answer 27

Urate

Question 28

Medical dissolution for urate stones is _________ (useful/not useful) in cats

Answer 28

not useful

Question 29

In dogs, diet management of urate stones is ___________ (useful/not useful)

Answer 29

useful

Question 30

What stone is the following describing? - Very rare in cats - DSH and Siamese cats - Defect in renal tubular transport

Answer 30

Cystine

Question 31

What stone is the following describing? - Rare (esp. females) but getting more common, frequently recur in dogs - acidic urine pH - Defect in renal tubular transport

Answer 31

Cystine

Question 32

You have an 11-year-old female spayed miniature schnauzer that you just removed 4 calcium oxalate stones from by cystotomy. This was the first time this dog had stones. What sort of post-op plan will you make?

Answer 32

Increase water intake, add potassium citrate to the diet and radiograph every 3 months to monitor for recurrence

Question 33

Nephroliths in SA We do not generally remove them unless:

Answer 33

- Recurrent UTI - Evidence of obstruction of ureter/renal pelvis - Evidence of pain

Question 34

Match the ureter sizes with the correct species: - 1.3 - 2.7 mm diameter - 1 mm outside, 0.4 mm lumen

Answer 34

- Canine - Feline

Question 35

- May indicate previous obstruction and permanent renal damage - Clinically significant obstruction is often seen on the "BK" side

Answer 35

Big Kidney, Little Kidney

Question 36

Ureteral are made of smooth muscles, what medications might you use to relax the muscles?

Answer 36

Prazosin - alpha 1 antagonist, can lead to hypotension Tamsulosin - alpha 1A specific, less risk of hypotension