Predispositions for Calcium Oxalate Urolithiasis in US Dogs

In the Literature

Hunprasit V, Schreiner PJ, Bender JB, Lulich JP. Epidemiologic evaluation of calcium oxalate urolithiasis in dogs in the United States: 2010–2015. J Vet Intern Med. 2019;33(5):2090-2095.

The Research …

The prevalence of calcium oxalate (CaOx) urolithiasis is increasing, and CaOx is the most frequent urolith submitted for analysis in the United States.¹ Previous studies have identified breed predispositions for CaOx urolithiasis, but these were not conducted within the last decade and did not account for breed popularity in the United States.<sup1,2 sup> 

This study* sought to identify breeds at high and low risk for CaOx urolith development. Dogs that had CaOx uroliths analyzed at the University of Minnesota Veterinary Medical Center from 2010 to 2015 were compared with 3 control groups during the study period: 

• Dogs that formed nonCaOx uroliths 

• Dogs admitted without urinary tract disease

• A population from a breed popularity survey during a similar time period (2013-2016)

Breeds were considered to be at high or low risk if their odds ratio from all 3 control populations was >1 or <1, respectively, and statistically significant. Age and sex were also compared among the groups.

The following breed predispositions were identified:

|

• Bichon frise

• Brussels Griffon

• Cairn terrier

• Chihuahua

• Jack Russell terrier

• Japanese chin

• Lhasa apso

• Maltese

• Miniature pinscher

• Miniature schnauzer

• Pomeranian

• Yorkshire terrier

|

• American bulldog

• American Staffordshire terrier

• Australian cattle dog

• Australian shepherd

• Basset hound

• Beagle

• Border collie

• Boxer

• Chow chow

• French bulldog

• German shepherd dog

• Golden retriever

• Labrador retriever

• Siberian husky 

|

Odds ratios also increased with male dogs, neutered dogs, and older dogs, although risk may decrease after 10 years of age. The mean age at discovery of the first CaOx urolith was 8.4 ± 2.8 years, with Brussels Griffons, Yorkshire terriers, and Pomeranians forming CaOx uroliths ≈1 year earlier.

… The Takeaways

Key pearls to put into practice:

• Risk for CaOx urolithiasis increases based on breed, increasing age, and neutered male signalment.

• Based on this study’s results, annual screening for CaOx uroliths in high-risk breeds should begin between 5 and 6 years of age or sooner if additional risk factors (eg, persistent CaOx urolithiasis, family CaOx urolith history, breed predisposition to CaOx urolith formation at an earlier age) exist.

• Annual screening for CaOx uroliths in high-risk breeds may help reduce the need for surgery, allow earlier interventions that prevent urolith recurrence, and allow earlier identification of predisposing comorbidities (eg, hypercalcemia, hyperadrenocorticism).

*Funded by Anadamahidol Foundation and Hill’s Pet Nutrition