Photo by Richard Weller-Poley
Anya was a keen agility competitor

A HEALTHY five-year-old dog died of kidney failure after eating a bag of raisins at its owner’s home. The toxicity of raisins and the proscribed veterinary treatment is known in the United States, but not in the UK and vets allegedly did not take heed of information passed to them from US veterinary websites by the dog’s owner until it was too late.

Kate Prosser from Cornwall, who shows Hungarian Vizslas under the Aurildis prefix has told her story to OUR DOGS in the hope that it will give vets and dog owners greater awareness of the subject and prevent similar deaths occurring in the future.

Kate’s five year-old Vizsla bitch, Aurildis Athena - known to all as Anya Beagle died on 15th January at Langford Veterinary College in Bristol after battling with Acute Renal Failure since she stole and ate a 500g bag of raisins just five days previously.

"It all seemed pretty harmless to start with," recalls Kate. "Anya stole and ate the bag of raisins in the morning of Saturday 11th, then immediately vomited the lot up. She seemed okay during the day and I wasn’t unduly concerned about her, but she felt rather cold to the touch in the evening. On the Sunday morning I’d found that she’d been sick again overnight and seemed very lethargic and poorly, so within one and half hours I took her straight to the vets."

Kate had recalled an article published some weeks earlier in OUR DOGS about dogs which had suffered from eating preserved fruit. Her vet said that he had "never heard of" dogs being poisoned in this way and simply gave Anya an anti-emetic injection to stop her vomiting - which was questionable in any event.

"Anya simply wasn’t recovering," says Kate. "I was horrified when I came across a letter in the latest issue of the Journal of the American Veterinary Medical Association (JAVMA) from veterinarians at the ASPCA’S animal poison control centre and then read the article on the ASPCA website. I took Anya back to the vet, showed him the article and he finally conceded that there might be something in it and took a blood test from Anya. He was as shocked as I was when the test result showed that she had renal failure."

Anya was put on a drip and, after 48 hours seemed better for being rehydrated and even managed to urinate a little, but a further blood test revealed that the toxin level in her body was higher, indicating that her kidneys were not functioning. Kate suggested that Anya be given peritoneal dialysis as indicated in the article, but her vet told her they had no facility for this at the local practice. "He said that the only place they might be able to do the dialysis was at the Langford Veterinary College in Bristol," says Kate. "I said I’d take her anywhere if it meant she’d get the right treatment.

"This was now Wednesday morning and her condition deteriorated, so I drove her down to Bristol. The peritoneal dialysis involves an operation to remove fatty tissue that enables a catheter to be inserted. I was told that it’s a very aggressive operation and that in Anya’s case there was only a slim chance of success. She went into theatre at 7.30pm, after which they gave her the dialysis. However, they telephoned me at 10pm to tell me that her condition had worsened and that she had no chance of recovery, so I agreed that the best thing to do would be have her put to sleep to prevent her suffering any further."

Naturally, Kate was devastated by the loss of Anya and horrified by the apparent lack of veterinary awareness of fruit poisoning in dogs in this country. "Anya was a very fit dog, she was a regular entrant in agility competitions and was qualified for the ABC finals this year," says Kate. "It was a freak accident that she ate the raisins and that she was poisoned in this way. I can’t say for certain whether she would have lived if she’d been treated earlier, but I do feel that vets in the UK should be aware of the problem and treat it seriously. My vet says he will write something in the Veterinary Record about this and I would hope that information on raisin toxicity will be made available to vets in this country. If it prevents another dog from dying in the way that Anya did, then that has got to be worthwhile."

Aggressive treatment

In a recent issue of Journal of the American Veterinary Medical Association (JAVMA) contains a letter and report from veterinarians at the ASPCA animal poison control centre (APCC) and their report, although preliminary, is worth noting.

The vets report 10 dogs going into renal failure due to excessive consumption of grapes (5 dogs -- fresh from vines or store or crushed and partially fermented, 3 dogs consumed seedless red grapes) and raisins (5 dogs). Two dogs died and 3 had to be put to sleep. The other five required aggressive treatment lasting up to 3 weeks. The estimated amounts consumed were known for four dogs and ranged from 9oz to 2lbs. Any dog consuming more than the odd grape or raisin should, in their opinion, be treated aggressively.

The cause of poisoning is not yet known, suggestions include: mould, excessive Vitamin D3 or similar, environmental contamination - pesticides, heavy metals -- or toxic substances in the fruit itself. Signs of illness include vomiting, diarrhoea, lethargy, loss of appetite and abdominal pain before the renal failure is apparent.. The signs can be present for weeks after eating the grapes or raisins.

The APCC runs the AnTox TM database, a computerised system that contains nearly 500,000 animal-related medical conditions and that enables veterinarians to quickly identify toxic-substance exposures, recognize clinical signs and administer proper treatment. By tracking cases in this registry, similarities in animal medical conditions nationwide can be logged and syndromes can be identified.

The database shows that dogs that consume grapes and raisins typically vomit within a few hours of ingestion. Most of the time, partially digested grapes and raisins can be seen in the vomit, faecal material, or both. At this point, some dogs will stop eating (anorexia), and develop diarrhoea. The dogs often became quiet and lethargic, and show signs of abdominal pain. These clinical signs last for several days -- sometimes even weeks.

When veterinary care is sought, blood chemistry panels show consistent patterns.
Hypercalcemia (elevated blood calcium levels) is frequently present, as well as elevated levels of blood urea nitrogen, creatinine and phosphorous (substances that reflect kidney function). These chemistries begin to increase anywhere from 24 hours to several days after the dogs eat the fruit. As the kidney damage develops, the dogs would produce little urine.

When they can longer produce urine, death occurs. In some cases, dogs that received timely veterinary care still have to be euthanised.

Even though the exact cause of the renal failure is unknown, dogs that ingest grapes and raisins can be treated successfully to prevent its development. The first line of treatment is decontamination. Inducing vomiting in recent ingestions and administering activated charcoal helps prevent absorption of potential toxins. Dogs should be placed on intravenous fluids for a minimum of 48 hours. A vet should monitor blood chemistry daily for at least three days following the ingestion.

If all blood work is normal after three days, it's unlikely that kidney failure will occur. If a dog shows evidence of renal failure, fluids must be continued, and other medications should be used to stimulate urine production. Some dogs may need peritoneal dialysis, a process where the peritoneum (the membranes surrounding the abdominal organs) is used to filter waste products that are normally filtered by the kidney.