Cystitis, though typically uncommon in horses, is characterized by an inflammation in the bladder. It is not often outwardly apparent that the bladder is inflamed, but there are other signs of cystitis that may be apparent. Some of the more obvious signs are excessive urination, blood in the urine, or dribbling of urine without full voiding of the bladder. Cystitis tends to affect mares more so than stallions.

Symptoms and Types

• Increase in the frequency of urination
• Poor production of urine
• Painful or uncomfortable urination
• Unusual urine consistency or appearance
  • Thick, cloudy urine
  • Bloody urine
  • Pus in urine
  • Blood clots in urine
  • Particles in urine

Causes

Cystitis is usually the result of calcium deposits in the bladder, commonly known as bladder stones. In addition, a vaginal infection may also lead to cystitis in mares. In some instances, if any injury has occurred, such as when the bladder or urethra is damaged in the course of a mare birthing a foal, cystitis may occur as a secondary condition to that injury. As a result of an injury to the bladder, the muscles of the bladder organ are not able to efficiently void the fluid that passes through it, resulting in sediment settling on the floor of the bladder and consequently, to inflammation of the bladder lining.

Diagnosis

You will need to give a thorough history of your horse's health and onset of symptoms. The history you provide may give your veterinarian clues as to which organs are causing secondary symptoms, are that are also being affected. The kidney, for example, may also be under duress, either as a result of the bladder inflammation, or concurrently. A complete blood count will be conducted, along with a urinalysis. An increased number of white and red blood cells in the urine is a clear indication of infection or inflammation of the bladder organ.

An internal examination is usually required, and this can be performed diagnostically by endoscopy, which uses a slender tube with an attached camera that can be inserted into the body. In this case, the endoscopic tool is a cystoscope. This will be inserted into the urethra and guided through the urinary tract into the bladder.

An analysis of the sediment in the bladder will also need to be done, which will necessitate a sample being taken from the bladder. This can be done by lavage. Using a catheter that has been inserted into the urinary tract, isotonic solutions can be injected into the bladder space, and as the solution washes back out of the bladder, it carries the sediment and stones out with it. This fluid can then be cultured and analyzed. In some cases, the horse may need to be tranquilized before a catheter can be inserted.

X-ray or ultrasound imaging can also be useful for viewing the internal structure of the bladder, as the bladder stones can often be seen specialized equipment.