Greyhounds provide model for E. Coli food poisoning in humans
In racing greyhounds, it's called Alabama Rot; in people, E. coli food poisoning or hemolytic uremic syndrome. Both can cause acute renal failure, sometimes death, and both are believed caused by the E. coli bacteria.
Brad Fenwick and Laine Cowan, veterinarians at Kansas State University's College of Veterinary Medicine, believe the similarity of the diseases between greyhounds and humans will provide a major step in researching the diseases caused by the deadly bacteria Escherichia coli, commonly known as E. coli. The bacteria is common to the environment and can be found in undercooked or raw ground meat.
"The disease in greyhounds appears to be the best model of the human disease. Using dogs as a model, we will be able to gain a better understanding of the underlying disease process, innovative approaches to treatment, and hopefully ways to prevent hemolytic uremic syndrome. It will allow us to conduct studies that simply have not been possible previously," said Fenwick, associate professor of veterinary pathology.
The greyhound disease was first recognized at a greyhound race track in Alabama, although now it occurs nationwide. Racing greyhounds are fed raw ground meat which makes them prime candidates for E. coli exposure. E. Coli food poisoning in humans also is caused by eating poorly cooked meat. The hemolytic uremic syndrome is a life-threatening disease and the most common cause of acute kidney failure in infants and children. Adults, adolescents and newborns also can be infected.
In research on "Alabama Rot" in greyhounds, Cowan found a striking similarity between the changes in the kidneys of infected greyhounds and humans with hemolytic uremic syndrome.
"In dogs, because the blood supply to the skin also is affected, the disease usually starts with ulcers on the skin. Like in humans, some of the dogs also have kidney failure due to blockage of the blood supply to part of the kidney," said Cowan, assistant professor of small animal medicine. "Humans don't get the skin form, but when the disease advances to the kidney failure stage in both humans and dogs it is almost identical."
The problem with E. coli infection is that there is no cure, Fenwick said. "The toxins produced by the bacteria attack the cell lining of the blood vessels. When people and dogs are infected there is no specific therapy. Only the symptoms such as diarrhea and dehydration can be treated. That's why the discovery of an animal model is so important."
Cowan and Fenwick began researching the greyhounds in 1993. Sick greyhounds from around the country were referred to the K-State veterinary clinic for care. Only recently have K-State researchers discovered what was causing the disease in the dogs.
"We found that antibiotics and anti-inflammatory drugs have no recognizable effect," Fenwick said. "But the good news is, like in humans, the dogs respond to supportive care."
Supportive care can involve intravenous fluids, transfusions and dialysis, the same treatment provided to children with hemolytic uremic syndrome.
This research is supported by a grant from the Kansas Racing Commission and the National Greyhound Racing Association.
November 2, 1995