Term
| Tell me about struvite uroliths. |
|
Definition
-50% of all uroliths in dogs; 40-50% in cats.
-yellow-white, hard, chalk-like powder when crushed.
-Usually radio-opaque
-More likely to precipitate in alkaline urine (less soluble at higher pH)
-Can result from UTI with urease-producing bacteria (esp. S. aureus) due to increase in urine pH. |
|
|
Term
| Tell me about urate uroliths. |
|
Definition
-8% of all uroliths
-small, green to yellow-tan
-Often radiolucent
-More likely to appear in acidic urine
-Dalmatians, English bulldogs
-Dogs with chronic hepatic insufficiency |
|
|
Term
| Tell me about cystine uroliths. |
|
Definition
-1% of uroliths
-yellow, usu. small, crushable
-Often radiolucent
-More likely found in acidic urine
-English bulldogs, Welsh corgis, dachshunds, Newfoundlands |
|
|
Term
| Tell me about calcium oxalate uroliths. |
|
Definition
-30% of uroliths (dogs); 50-60% (cats); male predominance
-white/cream, hard and brittle, rough, jagged, quartz-like appearance
-radioopaque
-solubility doesn't vary w/in urine pH range
-dietary factors: low dietary Ca++ |
|
|
Term
| Tell me about silica uroliths. |
|
Definition
-"jackstone" appearance
-radio-opaque
-solubility not pH dependent
-associated with high dietary intake of silica
-more common in male dogs
-GSD, Labs, Golden Retrievers |
|
|
Term
| Tell me about calcium phosphate (apatite) uroliths. |
|
Definition
<1% of uroliths (dogs)
-Predisposing factors: primary hyperparathyroidism, renal tubular acidosis, excess Ca++ and P- intake
-very radio-opaque
-more likely in alkaline urine (more soluble in acid urine) |
|
|
Term
| What uroliths are common in ruminants? |
|
Definition
1. Struvite (feedlot cattle on high grain rations): form gritty sludge.
2. Oxalate (sheep grazing grain stubble): low Ca++ diet in steers can cause.
3. Silica (pastured ruminants): common. Precipitation in urine requires proteins.
4. Clover stones (sheep grazing estrogenic pastures or injected with estrogen): can appear as urethral obstruction, stone in renal pelvis, or soft paste in urethral process (male sheep). |
|
|
Term
| What uroliths are common in horses? |
|
Definition
| Calcium carbonate or calcium phosphate. Can be normal; not usually associated with infection. Bladder stones most common. Can be asymptomatic or cause hematuria post-exercise, colic pain. |
|
|
Term
| What are 3 causes of FLUTD? |
|
Definition
1. Bacterial infection
2. Urolithiasis
3. Idiopathic (about 65%!) |
|
|
Term
| Differentiate between obstructive and non-obstructive FLUTD: |
|
Definition
Obstructive: male cats. Mucoprotein with embedded crystals; not urolith.
Non-obstructive: lower UT signs (hematuria, stranguria, pollukiuria, inappropriate urination).
Can't tell thetwo apart based on history; need physical exam/imagine to evaluate bladder size, urethral patency. |
|
|
Term
| What change in the frequency of feline uroliths has occurred over the past 20 years? |
|
Definition
| From 90% struvite stones, struvite has decreased to 40-50% and calcium oxalate stones have increased to 50% of total. This is likely due to acidifying diets meant to control struvite stones. |
|
|
