Polycystic kidney disease (PKD) is a hereditary kidney disease mostly found in Bull Terriers than any other breed. PKD is inherited when dogs who receive a defective copy of the gene from either one of their parents (autosomal dominant inheritance) who will pass it on to up to 90% of an affected litter.
After a thorough physical exam, your veterinarian will likely perform blood tests. These tests typically include a complete blood cell count (CBC) and serum biochemistry. Your dog’s CBC may show evidence of anemia, which can occur when diseased kidneys fail to adequately stimulate red blood cell production. Your dog’s serum biochemistry will likely show elevations in three indicators of kidney function: BUN (blood urea nitrogen), creatinine, and SDMA (symmetric dimethylarginine). There may also be abnormalities in electrolytes and elevations in calcium and phosphorus. A urinalysis should also be performed. This test involves analyzing the chemical composition of your dog’s urine, as well as examining the urine under a microscope. A urinalysis can indicate how well your dog’s kidneys are functioning and if your dog is losing protein through the urine, which is common in dogs with polycystic kidney disease. It will also look for the presence of a urinary tract infection and crystals. Imaging is often required to detect polycystic kidney disease. X-rays can sometimes show visibly enlarged and irregular kidneys but may not be sensitive enough to diagnose early polycystic kidney disease. Ultrasound is typically recommended. It provides a much more detailed view of the kidneys, allowing small, individual cysts to be detected, even in young puppies. Additional diagnostic tests may include genetic testing, histopathology (examining kidney tissue under a microscope), and computed tomography (CT scan). Given the increased risk of this condition in Bull Terriers, genetic testing is recommended to screen Bull Terriers prior to breeding.
Bull Terrier hereditary nephritis is another inherited renal disease, but it is inherited as an autosomal dominant condition. Evidence for an autosomal dominant inheritance includes the demonstration of at least one affected parent for each diseased offspring, the approximately equal numbers of affected males and females, and the occurrence of nephritis in each generation. Diseased bull terriers present from early life through to late adulthood with signs of renal failure. Proteinuria can be demonstrated in all affected animals, and an elevated urinary protein creatinine ratio (UPC) is a consistent indicator of subclinical disease. The rate of progression to renal failure varies, with death occurring at ages ranging from a few months to 10 years.
Testing is by the collection of a midstream urine sample (the first of the day) in a sterile container which is then sent to a lab for Protein: creatinine ratio analysis. The UPC will be returned within 24 hours and it is recommended to be 0.3 or under. UPC of over 0.3 does not necessarily mean the dog has hereditary Nephritis and further tests should be performed to rule out a urinary tract infection.
Hereditary Nephritis - Kidney
Inherited Kidney Diseases in Dogs and Cats
