The ASPCA Animal Poison Control Center has received more than 50 well-documented reports of dogs developing acute kidney failure after ingesting grapes or raisins. As more cases were reported, enough information was generated in the database to help veterinarians identify and treat dogs at risk. In all of the cases, the ingredients for potential acute kidney failure were the same. Injested grapes and raisins were from a variety of sources. Some were commercially prepared products of various brands purchased at grocery stores and some were grown in private yards. Ingested amounts varied considerably. The cases came from across the United States.

According to the preliminary data, the affected dogs generally began vomiting within six hours of ingesting the fruit. Most of the time, partially digested grapes or raisins could be seen in the vomit, fecal material or both. At this point, some dogs would stop eating and develop diarrhea. The dogs often became quiet and lethargic and showed signs of abdominal pain. These clinical signs lasted for several days, sometimes even weeks. In a vast majority of cases, the dogs continued to vomit and became depressed, at which point veterinary care was sought. The results of the blood tests showed consistent patterns.

Elevations in creatinine and BUN, as well as hypercalcemia and hyperphosphatemia have been reported. The abnormal blood levels would increase anywhere between 24 hours to several days after the dog ate the fruit. Kidney damage was evident in most cases within 72 hours from ingestion. As the kidney damage developed, some dogs would produce only small amounts of urine. When they could no longer produce urine, death occurred. In some cases, dogs that received timely veterinary care still had to be euthanized. Only half the dogs that received aggressive treatment, which included intravenous fluids and medications, had fully recovered.

In an attempt to determine the causative agents or disease processes, veterinary toxicologists at ASPCA Animal Poison Control Center have screened the suspected grapes and raisins for various pesticides, heavy metals, and mycotoxins (fungal contaminants) and so far, all results have come back negative. In the cases where the grapes were grown in private yards, owners confirmed that no insecticides, fertilizers or antifungals had been used on the fruit.

The first line of defense is decontamination. Inducing vomiting in recent ingestion and administering activated charcoal helps prevent absorption of potential toxins. Dogs should be hospitalized and placed on a diuresis of intravenous fluids for a minimum of 48 hours. Blood work should be monitored daily for at least three days following ingestion. If all blood work is normal after three days, it's unlikely that kidney failure will occur. If a dog shows evidence of kidney failure, fluids must be continued, and other medications should be used to stimulate urine production.

To reach The ASPCA Animal Poison Control Center hotline call (888) 426-4435 or use their website http://www.apcc.aspca.org/