Cystitis

CYSTITIS

Cystitis is the name given to inflammation of the urinary bladder or, more specifically, the epithelium (lining of the bladder). It is a commonly diagnosed condition in dogs of both sexes.

What are the causes?

The most common cause of cystitis in dogs of both sexes is an infection due to bacteria. The infection is described as ascending, when it comes from the exterior of the body and enters by way of the urethra (which is the tube from the bladder to the exterior) or it may be caused by an infection descending from the kidney.

Sometimes cystitis is caused by some other physical condition. Examples are urinary retention when the dog is unable to pass urine due to a blockage. Irritation from bladder stones, tumours or some neurological problem which interferes with normal bladder function.

What are the signs of cystitis?
Blood in the urine (haematuria) is the most common sign, coupled with increase in frequency. Sometimes there is straining and the dog will spend several minutes passing only a small quantity of urine (dysuria). The signs vary according to the cause of the cystitis. Bacterial infections usually cause haematuria and dysuria. Bladder stones are often quite rough. They therefore cause irritation to the bladder as they rub against the lining epithelium. This creates haematuria and dysuria.

Tumours or polyps of the lining of the bladder are not usually very irritating but they bleed easily and will also often result in dysuria.

Is cystitis serious?
Anyone who has had cystitis will know how uncomfortable even mild bacterial cystitis can be. However the seriousness of the condition really depends on the cause. Urinary obstruction is extremely serious. This in turn causes a very severe cystitis. Urinary obstruction can happen in any dog for a variety of reasons but it is more frequently seen in males due to their long narrow urethra in which stones can become lodged. However irrespective of sex, any dog showing straining with poor urine flow should be regarded as an emergency. Contact us without delay.

How is cystitis diagnosed?
If you can collect a urine sample before you bring in the dog this will be helpful but make sure that the container is scrupulously clean. Jam jars often contain traces of sugar which could lead to a false urine analysis.

The diagnosis depends on the history of haematuria, dysuria and frequency. Tests are carried out which include a urine analysis and examination under a microscope when often crystals will be detected which can be a cause.

Urine culture will detect bacterial cystitis and give an indication of appropriate antibiotics that can be used for treatment. During the initial examination bladder palpation involving gently feeling the bladder through the body wall will be carried out. This is to detect any abnormality such as thickening of the bladder.

Sometimes the presence of stones can actually be felt during this procedure.

Depending upon the results of the initial test further tests including x-ray, both plain and contrast radiographs, can be carried out. Plain x-rays will visualise most bladder calculi (stones) but some can only be viewed when special contrast materials are used, the most common of which is air which is introduced into the bladder prior to the x-ray being taken.

Ultrasound can also be used. Such scans are useful to indicate thickening of the bladder wall which occurs in chronic cystitis and also the presence of polyps or tumours.

If the patient is showing signs of general illness such as a fever (pyrexia), poor appetite or is generally unwell, more general tests including blood tests are likely to be carried out.

Most cases of cystitis in dogs are due to bacterial infection. Once the causal organisms have been identified as a result of tests, which also include the sensitivity of the bacteria to antibiotics, antibiotic treatment is usually very effective.

If the cystitis is due to calculi (stones) these again have to be analysed. Some can be dissolved with special diets while others require surgical removal following which drugs to change the pH (acidity) of the urine may be necessary long term together with special diets to prevent their recurrence.

This client information sheet is based on material written by Trevor Turner, BVetMed, MRCVS, FRSH, MCIArb, MAE.

Used with permission under license.