Dog Bladder Stones (aka uroliths, cystic calculi)
Many types of bladder stones affect dogs and cats. The most common stones are struvite, calcium oxalate and urate. Each of these stones form under different medical circumstances and some breeds are genetically predisposed to the development of particular stone types.
How bladder stones form. All bladder stones are formed from the presence of excess minerals in the urine. These minerals first appear as crystals suspended in the urine. Eventually as the concentration of crystals increases, they fall out of suspension and create bladder "sand". Over time, this sand becomes full-fledged stones.
Treatment of dog bladder stones. The treatment of bladder stones varies depending on the type of stone present. Often your veterinarian will recommend surgery, prescription diet therapy and sometimes medication. Your pet may require long term treatment because "once a stone former, always a stone former". The best treatment is prevention and there are several things you can do to lessen the risk of your pet developing bladder stones.
Prevention of bladder stones
Increase water consumption. This is undoubtedly the most important step in preventing canine bladder stones! Drinking more water produces dilute urine. Dilute urine contains less concentrated minerals so they are less likely to form crystals and then stones. Encourage your pet to drink by placing extra bowls of water around the house or use a pet-designed continuous water fountain to keep them drinking! Also, feeding canned diets or adding water or light salt to your pet's dry food will ensure they are getting more water.
Urination removes minerals and crystals from the bladder, therefore decreasing the chance of stone development. Good "potty training" usually results in infrequent urination. Dogs are often trained to "hold it" while their owners are at work. Unfortunately, holding urine for long periods of time increases the chance of forming canine bladder stones. Get someone to walk your dog in the middle of the day—it is good prevention for bladder stones and it increases physical activity to avoid obesity. For cats, keep their litter box clean to encourage a pleasant environment they wish to visit several times daily to urinate.
Too much of a good thing is not always wonderful! High levels of minerals like magnesium, phosphorus and calcium have been linked to dog bladder stone formation. Avoid feeding pet foods or giving supplements that contain excess minerals. Certain types of stones form in pets fed excess amounts of protein and this practice should be avoided.
Treat bladder infections.
Some bladder stones develop rapidly if there are bacteria present in the bladder. If your pet experiences problems with urination, seek prompt veterinary attention to identify and treat infections to prevent bladder stones from developing.
Donna Spector, DVM, DACVIM,is a renowned, board-certified Veterinary Internal Medicine Specialist who has practiced at the Animal Medical Center in New York City and other leading institutions. She is an active member of the American Veterinary Medical Association (AVMA) and the American Holistic Veterinary Medical Association. Dr. Donna has written and lectured extensively on topics including nutrition, diabetes, gastrointestinal disorders, kidney failure and respiratory disease. She is widely recognized for her role as consulting veterinarian to HALO, Purely for Pets, her TV appearances with Ellen DeGeneres and her widely-quoted pet health advice in print and on radio. Dr. Donna performs medical, nutrition and weight loss consultations for dogs and cats through her web-based veterinary consulting service, www.SpectorDVM.com.
Canine and Feline Lower Urinary Tract Disease, Chapters 266 and 267 (pages 1828-1874) in Textbook of Veterinary Internal Medicine, sixth edition, 2005, Elsevier Inc.