A few weeks ago I saw a young (and cute) little Bichon mix at our hospital because his owners had been noticing excessive thirst and urination for about two months. They had dropped off a urine sample the day before to rule out a urinary tract infection. The technician who analyzed the sample detected glucose in the pet’s urine and very astutely scheduled a doctor’s appointment right away.
When I met this dog (let’s call him Fido, to respect his desire for anonymity, which is also the name my husband applies to all strange dogs he doesn’t know), I was fully expecting to diagnose him with diabetes. However, he had not lost weight, if anything he had gained a few ounces and his appetite was not increased, which are normally hallmarks of the condition. Furthermore, his blood tests showed that his blood glucose was normal, and yet a repeated urine sample (taken directly from his bladder this time) confirmed the presence of glucose in his urine.
Coincidentally my esteemed colleague, Dr. Meriel Walsh had just diagnosed another patient a few months back with acquired Fanconi syndrome following the ingestion of jerky treats so my degree of suspicion was high that Fidomight be suffering from the same illness. Fido never had a jerky treat in his life, nor rawhide, but after a Columbo-like investigation of Fido’shabits, I found that he enjoyed several rawhide-free Milk Bones Gnaw Bones each night. Hmmm- the plot thickened. 🕵️
The FDA has been investigating cases of Fanconi-like syndrome since 2007 and although a link between the consumption of jerky treats and glycosuria with normoglycemia has been made, no specific causal agent has been identified to date.
One of the main functions of the kidney while eliminating waste, is to reabsorb glucose. Kidneys from dogs suffering from Fanconi syndrome fail in this function; but also a plethora of other various substances can be lost in the urine with this syndrome which can lead to permanent renal damage and chronic renal disease in some cases. Inherited Fanconi syndrome has been reported mostly in Basenjis and very rarely in other breeds like “ juvenile Norwegian Elkhounds, Miniature Schnauzers, and Shetland Sheepdogs”. 1
Acquired Fanconi syndrome however has been linked to various infections, medications, toxins, metals and more recently jerky treats ingestion. If treated early and by removing the offending substance most dogs recover without long term effects. However some dogs can sadly develop permanent renal damage.
But back to Fido: after doing my due diligence and ruling out infections and other toxins, we eliminated the Milk Bones Gnaw Bones from his diet. Fido was lucky in the sense that at the time of diagnosis he did not have evidence of renal issues or other metabolic imbalances and after 2 weeks I’m happy to report that he has stopped drinking and urinating excessively. He is not passing glucose in his urine any longer and things are looking up for Fido. Now there’s a happy ending!
I did report this to the FDA. I also attempted to contact the company that makes Milk Bones Gnaw Bones. As of this writing, they have yet to acknowledge my commentary. And although this particular treat is manufactured in China I am by no means making any conclusive accusations.
It could, after all, be an adverse reaction of this particular patient without there being an issue with this particular product. Until there is more information available I can only advise caution to all pet parents out there and recommend that you read all labels of pet foods and treats and make note of the place and date of purchase as well as lot numbers and UPC codes- you just never know.
The moral of this story is that while our pets can’t speak to us, by being tuned into them like this diligent owner was, we can usually succeed and staving off long term health conditions. And with a little bit of patience, collaboration and thinking, Columbo’s work seems well within reach to me!
Dr. Caroline Simard-Swimmer
Medical Director, Pets After Dark
1. Hostutler RA, DiBartola SP, Eaton KA: Transient proximal renal tubular acidosis and Fanconi syndrome in a dog. J Am Vet Med Assoc 2004 Vol 224 (10) pp. 1611-14,1605.
