Uroliths Flashcards
Struvite is radio____ and occurs in what species? How are struvite stones treated?
Radio-opaque stone common in cats (sterlie) and dogs (secondary to UTI). Also occur in cattle (alkaline urine + high dietary phosphate and magnesium levels).
- Dissolution protocol involves 1) Lower precursors (phosphorus, magneiusm, protein) 2) acidify urine below pH 7 3) increase moisture intake and 4) for dogs, treat UTI
Calcium oxalate are radio____ and are most common in ____. How are they treated?
radiodense, most common in cats. May occur in dogs (mini schnazuers, lasa apsos, yorkies) or ruminants. No dissolution protocol; lithotripsy or surgery is necessary.
Ammonium urate stones are radio____ and occur most commonly in ______ due to ______. Any dog with a _____ may also form urate stones.
Radiolucent
- Dalmation - reduced conversion of uric acid to allantoin
-Also occur in dogs with portosystemic shunts
- Allopurinol therapy may reduce uric acid production but it requires monitoring as it may predispose dogs to different types of stones (xanthine)
- Soy is high in purines and is not recommended for dogs prone to forming urate stones
Cystine
Radio-opaque
- breed predisposition
- renal tubular defect resulting in excess urine cysteine which is poorly soluble
- middle aged dog
- cysteine secretion decreased by castration, dissolution possible but expensive
Calcium carbonate stones occur in and require ____ for treatment.
- Most common type in horse and rabbit. Also occur in sheep grazing clover, ruminants on pasture high in calcium and oxalates. Surgical intervention is necessary.
Silicate stones occasionally occur in what breed of dogs?
- GSDs predisposed but rare
- seen in sheep and cattle grazing western U.S. rangelands
Apatite stones occur in what species?
composed of calcium and phosphate - feedlot cattle
Xanthine stones
Allopurinol is used in the treatment of urate stone forming in Dalmations. It acts by inhibiting the enzymes, xanthine oxidase, which metabolizes xanthine. The idea is that by stopping the purine metabolism pathway at this point, uric acid will not be formed in high quantities. However, if given at too high of a dose, xanthine will accumulate to levels where xanthine stones will form.
____ stones occur in cattle grazing on mature range grasses along with other factors including dehydration
Silicia
The radio-opaque stones are
Calcium oxalate, calcium phosphorus, struvite (usually) and silicia.
The most common urolith in cats is _____ whereas in dogs it is ______
Cats - calcium oxalate, Dogs - struvite. Although struvite is common in cats as well.
Struvite stones __[can/can’t]___ be dissolved whereas calcium oxolate stones _[can/can’t]____ be dissolved.
Struvite can be dissolved, CaOx cannot
Struvite stones in dogs are associated with _____ whereas in cats they are _____.
dogs - struvite associated with UTI. Cats - sterile.
____ stones occur commonly in feedlot cattle eating lots of grain
struvite