Disease overview

Urolithiasis is a term for the formation of stones (calculi or uroliths) in any part of the urinary tract. These stones form when the urine becomes oversaturated with certain minerals, such as urate, which is a non-water-soluble salt of uric acid. Normally, urate would be converted into allantoin, which is water-soluble and easily excreted in urine. Dalmatians have a hereditary genetic mutation that causes a defect in this pathway, which leads to direct excretion of uric acid before conversion. As uric acid is excreted, there is an increased risk of stone formation throughout the urinary tract.

Gene name

SLC2A9

Inheritance

Autosomal recessive

Signs and symptoms

Without stone formation, affected dogs will show no signs. As the stone develops, dogs will urinate more frequently, in abnormal places, with the possible presence of blood. If an obstruction forms, urination will cease with frequent straining. This is an emergency situation. Obstruction is more common in males. Stone formation may increase the chances of developing secondary infections.

How is it diagnosed

A veterinarian will conduct a thorough exam, including a review of health history and any clinical signs. Laboratory tests may be required, an ultrasound is needed to visualize any existing stones. Genetic testing is necessary to determine if there is an underlying genetic cause, which can assist veterinarians with diagnosis and help breeders identify affected and carrier dogs.

Breeds at higher risk

Citations

Bannasch D, Safra N, Young A, Karmi N, Schaible RS, Ling GV. Mutations in the SLC2A9 gene cause hyperuricosuria and hyperuricemia in the dog. PLoS Genet. 2008 Nov;4(11):e1000246. doi: 10.1371/journal.pgen.1000246. Epub 2008 Nov 7. PMID: 18989453; PMCID: PMC2573870.

Karmi N, Brown EA, Hughes SS, McLaughlin B, Mellersh CS, Biourge V, Bannasch DL. Estimated frequency of the canine hyperuricosuria mutation in different dog breeds. J Vet Intern Med. 2010 Nov-Dec;24(6):1337-42. doi: 10.1111/j.1939-1676.2010.0631.x. PMID: 21054540; PMCID: PMC5535792.

Karmi N, Safra N, Young A, Bannasch DL. Validation of a urine test and characterization of the putative genetic mutation for hyperuricosuria in Bulldogs and Black Russian Terriers. Am J Vet Res. 2010 Aug;71(8):909-14. doi: 10.2460/ajvr.71.8.909. PMID: 20673090; PMCID: PMC5551899.

Disclaimer

Disease diagnosis and treatment should always be performed by a veterinarian. The following information is for educational purposes only.