Other Names: Urolithiasis, HUU
Inheritance: Autosomal Recessive
Mutation(s): G>T
Affected Gene(s): SLC2A9
Affected Breed(s): American Bulldog, American Pit Bull Terrier, American Staffordshire Terrier, Aussiedoodle, Australian Labradoodle, Australian Shepherd, Biewer, Black Russian Terrier, Bulldog, Collie, Dalmatian, Danish-Swedish Farmdog, Drentsche Patrijshond, Dutch Partridge Dog, English Shepherd, Finnish Lapphund, French Bulldog, German Hunting Terrier, German Shepherd Dog, German Shorthaired Pointer, Giant Schnauzer, Greater Swiss Mountain Dog, Jack Russell Terrier, Jagdterrier, Kromfohrländer, Labradoodle, Labrador Retriever, Lagotto Romagnolo, Large Munsterlander, Mastiff, Miniature American Shepherd, Miniature Australian Shepherd, Parson Russell Terrier, Pomeranian, Rough Collie, Russell Terrier, Shiloh Shepherd, Smooth Collie, South African Boerboel, Spaniel de Pont-Audemer, Spanish Water Dog, Swedish Vallhund, Toy Australian Shepherd, Weimaraner, White Shepherd Dog, Yorkshire Terrier

Common Symptoms

Hyperuricosuria is an inherited condition of the urinary system affecting several breeds of dog. The SLC2A9 gene codes for a protein that allows the kidneys to transport uric acid from the urine. Dogs with mutations in both copies of the SLC2A9 gene are predisposed to have elevated levels of uric acid in the urine, hence the name hyperuricosuria. Uric acid can form crystals and/or stones (uroliths) in the urinary tract. Dogs with hyperuricosuria most commonly present with symptoms of recurrent urinary tract inflammation, which include frequent urination, blood in the urine, and straining to urinate. They may also have loss of appetite, lethargy, weakness, vomiting and pain. Urinary stones in the bladder can cause urinary tract infections or more seriously, blockage of the urethra. Both male and female dogs can be affected, but obstruction of urine flow is more common in males due to differences in anatomy. Although an x-ray can be used to exclude other types of stones, urate stones cannot typically be seen using x-rays and must be evaluated by ultrasound. Not all dogs with mutations in both copies of the SLC2A9 gene will have symptoms of disease, though they will have increased uric acid excretion in the urine.


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