Urolithiasis

Question 1

What is the difference between Uroliths and Crystals?`

Answer 1

Uroliths are macroscopic

Crystals are microscopic and do not cause clinical signs

Question 2

How are Uroliths formed?

Answer 2

Urine becomes supersaturated.

Question 3

How would you treat renal and ureteral stones?

Answer 3

Surgical removal
Urinary bypass
Dietary dissolution (only if non obstuctive and amenable to dissolution)

Question 4

How would you treat bladder stones?

Answer 4

Medical Dissolution
Voiding urohydropropulsion
Cystotomy

Question 5

How would you treat urethral stones?

Answer 5

Retrograde flush into bladder

Surgery

Question 6

What is urohydropropulsion?`

Answer 6

A process where you fill the bladder with saline and then position the animal so the urethra is vertical.
You then agitate the bladder then let the stones settle and then void the bladder hopefully with the stones exiting in the stream of urine.
Give 3 days Abx after this

Question 7

Struvite ?

Answer 7

Many breeds
Most dogs have concurrent UTI
Mostly Urease producing bacteria (staph Proteus)
Alkaline urine pH
Usually Sterile in cats
Moderately to markedly radiopaque
Single - smooth
Miltiple smooth pyradimal

Question 8

Struvite Tx

Answer 8

Treat UIT for 3-4 weeks
reduce urinary Mg, ammonium and phosphate
Maintain pH of 6.4
Low protien diet
Increase water intake

Question 9

Calcium Oxalate

Answer 9

Breeds - terriers poodles schnauzer burmese himalayan persian
More males than females
Older animals
Upper UT
Sharp projections, mulberry shaped or smooth round
Small uroliths and multiple nephroliths if present

Question 10

Calcium Oxalate Tx

Answer 10

Surgery
Urohydropropulsion
Medical dissolution not possible!

Question 11

Ammonium urate

Answer 11

Dalmatians predisposed
Hepatic dysfunction (PSS)
Bulldogs
Radiolucent
Miltiple smooth uroliths
Yellow green urolith colour

Question 12

Ammonuim Urate Tx

Answer 12

treat underlying liver problems.
dissolution possible
treat UTI
reduce purines and get urine to neutral or alkaline pH
Allopurinol - inhibits xanthine oxidase.

Question 13

Cystine

Answer 13

Renal Tubular defect
Congenital problem but diagnosed in middle aged dogs
Radiolucent
Medical dissolution effective but expensive
Cystine excretion reduced by castration
Multiple smooth round uroliths in bladder and urethra