Nephrolithiasis in Cats: 2025 Vet Insights 🐱💎

Hi, I’m Dr Duncan Houston BVSc, founder of Ask A Vet. Today’s comprehensive 2025 guide explores nephrolithiasis—or kidney stones—in cats. We’ll cover why stones form, identify clinical signs, walk through diagnostics, treatment options, prevention, and how tools like Ask A Vet, Woopf, and Purrz support your cat’s care at home and in clinic. Let’s get started! 🩺

📌 What Is Nephrolithiasis?

Nephrolithiasis refers to concretions—rare in cats—forming in the kidneys (renal pelvis) or ureter, often composed of calcium oxalate or struvite crystals :contentReference[oaicite:3]{index=3}. Though many stones are silent and incidental, larger or obstructive ones can compromise urine flow and cause significant harm :contentReference[oaicite:4]{index=4}.

⚠️ Who Gets Kidney Stones?

• Middle-aged to older cats are most affected :contentReference[oaicite:5]{index=5}.
• Breeds at higher risk include Persian, Himalayan, Burmese, and Siamese :contentReference[oaicite:6]{index=6}.
• Underlying chronic kidney disease, UTIs, dehydration, or metabolic imbalances predispose cats to stone formation :contentReference[oaicite:7]{index=7}.

🔍 How Stones Form

Stones originate from urine supersaturation, where minerals like calcium, oxalate, phosphate, and magnesium crystallize and aggregate :contentReference[oaicite:8]{index=8}. In cats, the most common types are:

• Calcium oxalate: Comprise about 98% of upper urinary stones; cannot dissolve medically :contentReference[oaicite:9]{index=9}.
• Struvite: Once common, now less frequent; using urinary acidifying diets reduces their occurrence :contentReference[oaicite:10]{index=10}.
• Other rare types: cystine, urate, calcium phosphate.

🧠 Signs & Symptoms

Small stones are often asymptomatic :contentReference[oaicite:11]{index=11}. When signs appear, look for:

• Hematuria—blood in the urine
• Straining or dysuria, if stones travel to bladder or ureter :contentReference[oaicite:12]{index=12}.
• Increased urination or pain
• Vomiting, lethargy, or reduced appetite if stones obstruct renal outflow or cause infections :contentReference[oaicite:13]{index=13}.

🔬 Diagnosis

The veterinarian will combine:

• Blood panel: To assess kidney health (BUN, creatinine, SDMA) and infection.
• Urinalysis & culture: Detect blood, crystals, infection.
• Imaging:
  • Ultrasound: Stones appear as bright, hyperechoic foci with shadows :contentReference[oaicite:14]{index=14}; can detect non-radiopaque stones. Also shows hydronephrosis if obstructed :contentReference[oaicite:15]{index=15}.
  • X-rays: Useful for radiopaque stones (e.g., calcium oxalate, struvite) :contentReference[oaicite:16]{index=16}.
  • CT scan: Most sensitive for stone detection but less commonly used.

🛠️ Treatment Strategies

1. Medical Management

• Struvite stones: Can dissolve with prescription diets and increased hydration :contentReference[oaicite:17]{index=17}.
• Calcium oxalate stones: Non-dissolvable—managed by removal if large or causing blockage :contentReference[oaicite:18]{index=18}.
• Hydration: Key to preventing new stones; encourage wet food and offer SC fluids via home-care kits like Woopf.

2. Surgical Removal

• Ureterolithysis: Ureteral stones may be removed via surgery or stent placement.
• Nephrotomy or ureterotomy: Surgical stones removal when causing obstruction or recurrent infection.
• Minimally invasive options: Some centers offer laser lithotripsy or shock wave but limited for cats.

3. Manage Complications

• UTIs: Treat with culture-based antibiotics.
• Pain: Address with analgesics like buprenorphine.
• Hydronephrosis: Manage by relieving obstruction and monitoring kidney function.

4. Monitoring & Follow-Up

Repeat imaging every 6–12 months to check stone status. Regular urinalysis and culture track infections. Kidney function monitoring is critical in obstructive cases.

🌱 Preventive Care

• Hydration: Offer wet food, water fountains, and home fluids via Woopf kits.
• Diet: Maintain urinary pH balance. For struvite, acidify urine; monitor as this may predispose to calcium stones :contentReference[oaicite:19]{index=19}.
• Avoid excess magnesium, phosphorus, and oxalate in diet.
• Regular wellness exams, especially for high‑risk breeds and cats with CKD.

🐾 Home Support Tools

• Ask A Vet: Telehealth consultations, diet adjustment, and stone-monitoring plans.
• Woopf: Home fluid administration kits for hydration support.
• Purrz: Track urination frequency, urine color, appetite, and weight to detect issues early.

🔬 2025 Advancements

• Enhanced ultrasound detects smaller nephroliths earlier :contentReference[oaicite:20]{index=20}.
• Non-invasive lithotripsy techniques being explored in veterinary medicine.
• AI-assisted imaging for better identification of at-risk cats.
• Gut microbiome studies suggest stone-linked changes may offer new prevention strategies :contentReference[oaicite:21]{index=21}.

✅ Vet‑Approved Care Plan

1. Identify stones with labs and imaging
2. Differentiate stone type: calcium oxalate vs. struvite
3. Treat urine infections and pain
4. Manage and remove stones via diet or surgery
5. Support hydration and nutrition
6. Monitor kidney function, ultrasound stones every 6–12 mo
7. Use Ask A Vet, Woopf, and Purrz for ongoing home care

✨ Final Thoughts from Dr Houston

Kidney stones in cats are challenging but often manageable. With timely diagnosis, thoughtful treatment, and consistent home and veterinary support, your cat can enjoy a comfortable, high-quality life. Our integrated tools—Ask A Vet, Woopf, and Purrz—ensure your cat has the best support system ever. You’re not alone on this journey. 💙🐾

Need help now? Visit AskAVet.com or download our app for personalized care plans and expert advice.