Urate Urolithiasis in Cats: Vet Metabolic & Care Guide 2025 🐱⚖️

Urate Urolithiasis in Cats: Vet Metabolic & Care Guide 2025 🐱⚖️

By Dr. Duncan Houston, BVSc

🔍 What Are Urate Stones?

Urate uroliths are rare urinary stones formed from ammonium urate or uric acid—linked to liver enzyme deficiencies or portosystemic shunts. These produce excessive urinary uric acid, forming stones, typically radiolucent and less visible on x-rays ([petmd.com](https://www.petmd.com/cat/conditions/urinary/c_ct_urolithiasis_urate?utm_source=chatgpt.com)).

1. Causes & Risk Factors

• Liver shunts (PSS): impaired liver metabolism → excess uric acid excretion. Epidemiologically identified in feline cases with urate stones.
• Genetic defects: lower uricase activity—common in Dalmatians but known in some feline lines.
• Diet & acidosis: high-protein diets with low urine pH heighten solubility of urate crystals.

2. Who’s Affected?

• Often young cats with congenital portosystemic shunts or metabolism issues.
• Breed predisposition is undefined; domestic shorthairs and mixed breeds are commonly reported.
• Stone formation may be first sign of silent liver shunt in an otherwise healthy cat.

3. Clinical Signs & Urinary Presentation

• Straining or repeated urination with small amounts, hematuria.
• Urine may appear cloudy or pale if pus or crystals present.
• Possible signs of liver dysfunction: stunted growth, neurologic signs, GI upset.
• Obstructive blocks occur sporadically, leading to acute urinary emergency.

4. Diagnostic Work‑Up

1. History & exam: assess urinary and hepatic symptoms—bruising, neurologic signs.
2. Bloodwork: CBC, chemistry showing elevated bile acids or liver enzymes; ammonia/fasting bile acids help identify shunts.
3. Urinalysis: reveals urate crystals (diamond-shaped), pH acid (<6.0), possible blood/casts.
4. Urine culture: rules out infection, which can compound signs.
5. Imaging: ultrasound to detect radiolucent stones, stones appear echogenic with shadowing; abdominal CT may show shunt.
6. Urethral catheterization: may retrieve stones if low urethra; stones sent for composition.
7. Portosystemic shunt imaging: via nuclear scintigraphy, CT angiography, or ultrasound where suspected.

5. Treatment Options

a. Medical Dissolution

• Potassium citrate/alkalinization to raise urine pH (~7.0). Dilutes crystal formation.
• Low-protein diets tailored for hepatic support and reduced purine intake.
• Allopurinol—blocks uric acid production; off-label in cats requires monitoring.
• High fluid intake encouraged via wet food and water fountains to dilute urine.

b. Interventional/Surgical Removal

• Cystotomy or urethrotomy to extract large or obstructive stones.
• Hydropropulsion in females may clear small stones noninvasively.

c. Correcting Liver Abnormalities

• Surgical correction of portosystemic shunts often essential to reduce stone recurrence.
• Liver meds—SAMe or lactulose support function.

6. Prognosis & Recurrence Risk

• Medical dissolution can be effective with 3–6 months of therapy and monitoring.
• Without shunt correction, recurrence is very likely.
• Outcomes after shunt ligation are good; stone recurrence low with successful surgery.

7. Prevention & Monitoring

• Diet low in purines + urine alkalinizing agents.
• Regular urinalysis every 3–4 months post-treatment and post-shunt surgery.
• Ongoing monitoring of liver function, bile acid tests, and imaging as indicated.
• Older cats’ diets may require adjustment after change in metabolism.

8. Ask A Vet Remote Monitoring 🐾📲

• 📸 Upload urinalysis reports and urine microscopy images.
• 🔔 Reminders for diet change, urine testing, alkalinization meds.
• 🧭 Track pH, stones, urinary output, appetite, neurologic signs.
• 📊 Alerts for relapse: hematuria, straining, neurologic decline.
• 👥 Virtual consults for therapy adjustment, diet updates, liver monitoring, and re-imaging plan.

9. FAQs

Can urate stones be dissolved?

Yes—soluble with alkalinization and low-purine diet over several months.

Do all cats with shunts form stones?

No—only some shunt cats become hyperuricosuric and susceptible.

Is allopurinol safe?

Use carefully—monitor kidney/liver values and ensure proper dosing.

Can stones indicate liver disease?

Yes—urate stones often prompt investigation that finds silent shunts.

10. Take‑Home Tips ✅

• Consider uric acid cause: stones + liver signs warrant shunt work-up.
• Use medical dissolution: combine alkali, low-purine diet, fluids, and possibly allopurinol.
• Correct shunts: surgery can prevent stone recurrence.
• Monitor regularly: urinalysis and liver tests every 3–4 months.
• Rely on Ask A Vet: for monitoring, alerts, and remote expert coordination.

Conclusion

Urate urolithiasis is rare but important in cats with liver metabolism disorders. With medical solubilization, shunt correction, diet changes, and fluid support, cats can avoid recurrence and maintain urinary health. Ask A Vet enhances care with lab image review, symptom alerts, medication reminders, and expert follow-up—ensuring top-tier support in 2025 and beyond 🐾📲.

If your cat forms urate stones or shows signs of liver disease, consult a veterinarian promptly and initiate Ask A Vet remote monitoring for integrated urinary and hepatic care.

© 2025 AskAVet.com • Download the Ask A Vet app for urine uploads, med reminders, diet support, liver monitoring, and remote veterinary guidance anytime 🐱📲