Incidences of kidney problems that mimic Fanconi disease, first identified in dogs in the United States and Australia last year, are continuing to show up Down Under, prompting one maker of chicken treats to recall its products this week.

KraMar Pet Company Pty Ltd. recalled its Supa Naturals Chicken Breast Strips 150G, product code 85148, and Supa Naturals Chicken Breast Strips 110G, product code 85149, after 15 sick dogs were found to have eaten the products, a company spokeswoman said. The dog treats are sold in Australia and New Zealand.

The company emphasized that it has no scientific evidence that its treats are causing the Fanconi-like syndrome. Fanconi is a usually inherited disease in which the kidneys do not properly resorb electrolytes and nutrients back in the body, but lose them in urine. Symptoms include excessive drinking and urination (polydipsia and polyuria) and glucose in urine (glucosuria).

“This syndrome and the associated cases have only been reported to us in the last three months,” spokeswoman Mary-Lou Jarvis said in an interview by e-mail. “During this time we have investigated with relevant veterinary scientists to verify a link with our product. Whilst no such link has been established, we have decided to withdraw the product on the basis of the 15 cases reported to us.”

However, Dr. Linda Fleeman at the University of Sydney, who is working with veterinary colleagues to identify the cause, said by e-mail that the researchers have received reports of dozens of dogs with glucosuria that ate KraMar chicken breast strips.

“Many dogs present with mild signs (e.g. polyuria and polydipsia and lethargy) and appear to make a full recovery with discontinuation of the treats and no other treatment,” Fleeman said. “The cases that present with inappetence and anorexia are the toughest. The electrolyte and acid-base disturbances are priorities at first, but once they are resolved, some cases have continued prolonged inappetence with weeks of e-tube feeding. It appears that dogs completely recover in the end, although it can take months for the glucosuria to resolve.

“However,” she added, “we really need to now keep track of affected cases to ensure that they do recover and to figure out how to best help them if they do not completely recover. We are obviously still in the process of collecting case data and will likely learn a lot more over the coming months.”

Fleeman said Dr. Mary Thompson at the University of Queensland diagnosed the first case in Australia at the same time that news of cases in the United States was released.

In September 2007, the American Veterinary Medical Association posted an alert on its Web site about complaints from pet owners and veterinarians that multiple brands of jerky treats manufactured in China appeared to be sickening pets.

At the same time, the American College of Veterinary Internal Medicine reported that some of its members in nephrology and urology were seeing an unusual number of dogs, typically small ones, that were vomiting, lethargic and anorexic. All had consumed jerky treats, mostly chicken, a few weeks before becoming anorexic. Most of the dogs recovered and their symptoms resolved within a few weeks.

AVMA spokesman Michael SanFilippo said the U.S. cases appear to have “flamed out” during the past year. “None of our members has contacted us since last year to report suspicious cases of Fanconi since then,” he said by e-mail.

SanFilippo said all the cases were referred to the U.S. Food and Drug Administration's (FDA) Center for Veterinary Medicine. “Despite extensive testing of suspected treats, no contaminant was ever identified,” he said.

Dr. Kendal Harr, a veterinary pathologist in Florida, said she has not seen or heard of recent cases, but had more than 100 at one point last spring. Harr reported in July in a Veterinary Information Network discussion that she was involved in phone calls that led the FDA to recommend voluntary removal of jerky treats from stores including PetSmart and Walmart.

“The treats come from China and have various distributors (in the States in California predominately, but there are others) — therefore, packaging was irrelevant in our cases, as the source of the shipment is coming in cargo ships from China,” she wrote.

Harr said she visited a Walmart where her client had purchased jerky treats and found product with mold, subsequently identified by Cornell University as Penicillium.

“I am certain that we are dealing with either a fungal toxin or an antifungal agent put on the treats for shipment,” she wrote. “It is causing acute tubular necrosis — hence the Fanconi's. If you catch these at the right stage and look at a urine sediment, it is loaded with cellular casts and renal cells. First stage is liver damage and vomiting, second stage is renal (acute tubular necrosis) — possibly a metabolite of the original toxin — never identified here, though looked for extensively ...”

She and others said the culprit was not melamine, the industrial chemical added to wheat gluten to boost its apparent protein content. The tainted gluten contaminated more than 150 brands of wet pet foods and prompted a massive recall in North America last year. A $24-million court settlement to compensate owners of animals that were sickened and killed is still being worked out.