Epidemiologic Evaluation of Risk Factors for Calcium Oxalate Urolith Formation and Recurrence in Dogs

Abstract

Calcium oxalate (CaOx) urolith is the most common urolith in dogs. The exact mechanism for CaOx urolith formation is not well understood but thought to be multifactorial. However, urolith recurrence is common after removal. Knowledge of which group of dogs are greater risk for formation and recurrence, can help veterinarians select effective therapy and prevention, as well as earlier recognize urolith formation or recurrence to increased opportunity for nonsurgical removal, early dietary modification to minimize urolith growth, early removal to avoid urinary obstruction, and early recognition of potential metabolic diseases Dogs which had a greater risk for CaOx urolith formation included; male, small breed (Bichon, Miniature Schnauzer, Lhasa Apso, Yorkshire Terrier, Pomeranian, and Maltese). To minimize the morbidity and mortality due to urolithiasis, these dogs should be prescreened at approximately 5 years-old. The recurrence of CaOx urolith is common. Small breed, male, dogs with history of previous urolithiasis, dogs 6 - 10 years old, and dogs with CaOx dihydrate were greater risk for recurrence. Therefore, intensive prevention therapy of these dogs will be benefit for minimizing recurrence. To detect early CaOx urolith recurrence, the screening by means of medical imaging should be performed at least once a year to minimize morbidity and permit simple non-invasive urolith removal in most. For prevention of recurrence, clinician should promote low urine specific gravity (< 1.030).