Murdoch University PhD graduate and veterinarian Dr Jeni Hood.

A study into an inherited kidney disease in bull terriers may lead to new treatments for a very similar inherited disease in humans called Alport syndrome.

Murdoch university PhD graduate and veterinarian Dr Jeni Hood, has found that bull terrier hereditary nephritis produces similar kidney lesions to those observed in people with Alport disease, making it a suitable animal model for testing screening and treatment methods.

Identification of early signs of the nephritis has led to the eradication of the disease from bull terriers in Western Australia, and has caused a drastic reduction in occurrence around Australia through widespread screening.

Before Dr Hood’s research, bull terrier breeders and veterinarians realised that dogs were dying of naturally occurring renal failure, but had only seen the nephritis in the late stages of the disease when the kidneys were too scarred to examine properly.

Urine samples demonstrated that there was albumin protein in the urine, indicating that the filtering systems, or glomeruli, of the kidneys were dysfunctional.

By using this simple sampling technique as a crude screening test and working back through the pedigrees of the dogs, Dr Hood established that the nephritis was an autosomal dominant hereditary disease – every dog that carried the gene was affected by the disease.

Using this information enabled bull terrier breeders to stamp out the fatal disease by not breeding from dogs that had protein in their urine.

Research showed that the lesions could be detected with a light microscope, providing a screening test that is much more specific than the urine test and much cheaper than examining the biopsy with an electron microscope.

Analysing the lesions in the kidneys in greater detail using the electron microscopes revealed that the disease affected the basement membranes of the capillaries that form the glomeruli.

“The basement membrane becomes thickened and split – rather like an old frayed piece of elastic,” explained Dr Hood.

“These lesions are identical to those seen in all forms of Alport disease.”

Dr Hood teamed up with Dr Judy Savige at Austin Hospital in Melbourne to further investigate the possibility of using bull terriers as an animal model for Alport disease, drawing funding from the Australian Kidney Foundation and the NHMRC (National Health and Medical Research Council).

“Alport disease is an incurable condition affecting 5% of all people needing renal transplants,” said Dr Hood.

“In Canada, the Samoyed dog has successfully been used as an animal model of another form of Alport syndrome (the X-linked dominant type) and affected dogs are apparently being investigated for use in gene therapy trials. Bull terriers could help in a similar way.”

Involving the examination of hundreds of bull terriers over a nine year period, this investigation is the largest completed study on canine renal disease in Australia to date, and is probably one of the largest in the world.

“The success of this project was due to the goodwill of the dog owners and bull terrier clubs, and because bull terriers are such gentle stoic dogs,” said Dr Hood.

“People were particularly pleased to help research that did not induce disease in the dogs and avoided the use of lab animals.”

Dr Hood is currently the Clinical Editor of the Australian Veterinary Journal, and aims to continue the research into nephritis in other dog species, including dalmatians.