What is the recommended management approach for calcium oxalate urolithiasis in dogs?

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Calcium oxalate (CaOx) uroliths cannot be dissolved medically and require physical removal, followed by lifelong prevention strategies to reduce the high recurrence risk. CaOx accounts for 41%–49% of all canine urolith submissions, and up to 50% of affected dogs experience recurrence within 2–3 years.24 Physical removal is the first priority for clinically significant CaOx urocystoliths. The current consensus guideline prioritizes minimally invasive retrieval — voiding urohydropulsion, cystoscopic basket retrieval, or intracorporeal laser lithotripsy — over open cystotomy.2811 Open cystotomy carries an incomplete removal risk of up to 20%, often due to poor visualization or hemorrhage.9 When open cystotomy is performed, intraoperative urethrocystoscopy reduces operating time and improves urolith detection in male dogs over 7 kg.9 Postoperative imaging is essential to confirm complete removal; incomplete removal may necessitate immediate revision surgery.9 For upper urinary tract CaOx uroliths, minimally invasive approaches are preferred to protect renal function. Extracorporeal shockwave lithotripsy (ESWL) is feasible for nephroliths ≤1.5 cm in diameter; endoscopic nephrolithotomy is recommended for nephroliths >1–1.5 cm or when ESWL is not suitable.5 Obstructive ureterolithiasis requires immediate intervention; ureteral stenting is the recommended minimally invasive approach in dogs.5 Non-obstructive nephroliths that are not causing recurrent infection, pain, or progressive renal parenchymal compression do not require removal.5 Prevention centers on reducing urine calcium oxalate relative supersaturation through dietary modification and increased water intake. Regardless of stone type, increasing water intake is the single most universally applicable intervention.1 The urine specific gravity target is ≤1.020 in dogs.7 Dietary management for CaOx includes low-oxalate ingredients, controlled calcium with an appropriate calcium-to-phosphorus ratio, and avoidance of vi