You might have observed symptoms of bladder stones in your pet, such as frequent urination or blood in their urine. Alternatively, your dog or cat might have appeared healthy, but bladder stones were found during a routine examination. In either case, you're likely curious about what bladder stones are and how they form.
Understanding Bladder Stones
Bladder stones, also referred to as uroliths or calculi, are hard deposits that form in the urinary bladder of cats, dogs, and other animals, including humans. These stones originate from tiny crystals in the urine, mainly composed of minerals such as calcium oxalate and struvite. These crystals, though initially microscopic, accumulate over weeks or months, eventually forming one or multiple stones that can vary in size from several millimeters to up to four inches in diameter.
As stones enlarge, they irritate the bladder walls, causing pain, irritation, and blood in the urine. This irritation can also lead to bladder wall inflammation, making it difficult for your pet to urinate while increasing the frequency of urination. If not treated, bladder stones can block the urethra, posing a life-threatening risk.
Reasons For Bladder Stones
While we understand how bladder stones form, identifying the exact cause can be challenging. Various factors can contribute to their development, such as infection, genetics, and urine composition imbalance.
In dogs, bladder stones can be triggered by bacterial infections, genetic predisposition, or an imbalance in urine pH (either too alkaline or too acidic). These factors promote the growth of specific minerals that form stones.
- Urinary tract infection: Bacterial infections can disrupt urine pH, facilitating crystal growth. Some bacteria produce an enzyme called urease, which further stimulates crystal formation. This infection-stone relationship is more common in dogs than cats.
- Dehydration: This leads to concentrated urine with a more acidic pH, increasing the likelihood of crystal formation. Dehydration also hampers the body's ability to expel any forming crystals naturally.
- High mineral levels: Elevated concentrations of certain minerals can lead to crystal and stone formation. This is often related to diet but can also result from medications, supplements, or metabolic issues.
- Certain breeds: Some breeds are more susceptible to bladder stones. Dogs include Bichon Frise, Yorkshire Terriers, Shih Tzus, Dalmatians, Dachshunds, Miniature Poodles, and Miniature Schnauzers. Siamese, Burmese, Himalayan, and Manx breeds are more prone in cats. Specific breeds may be more likely to develop stones of particular minerals.
