Steve San Miguel Zamorano
Causes of Cystitis/Lower Urinary Tract Disease in Cats
What is cystitis?
Cystitis is a general term referring to inflammation in the urinary bladder. The term cystitis does not imply a specific underlying cause.
In cats, diseases of the lower urinary tract (bladder and urethra) are often grouped under the term feline lower urinary tract disease (FLUTD). This is due to the fact that it can be difficult to distinguish between diseases of the bladder and urethra, and many diseases will affect both structures. It is more correct to call the condition Feline Idiopathic Lower Urinary Tract Disease (iFLUTD) to indicate that this is an exclusionary diagnosis made only after all the known causes have been eliminated.
What are the signs of FLUTD?
Typical signs in cats with FLUTD are inflammation and irritation of the lower urinary tract. Common signs are:
Increased frequency of urination
Difficulty in urinating or dysuria. These cats often spend a long time straining in the litter box while passing only small quantities of urine.
The presence of bloody urine or a foul odor.
Complete urinary tract obstruction resulting in the inability to urinate. These cats usually strain to urinate persistently without producing any urine.
With urinary tract obstruction, it is important to seek immediate veterinary care because blockage of the flow of urine can be a life-threatening complication if untreated.
What causes FLUTD?
There are a vast number of potential causes of FLUTD, but many cats experience severe inflammation of the bladder and/or urethra without an identifiable cause. This is known as ‘idiopathic’ or ‘unknown’ FLUTD. These idiopathic cases must be differentiated from other potential causes so that appropriate treatment can be given. Some of the potential causes of FLUTD are listed below:
Idiopathic - unidentifiable cause
Urinary calculi or bladder stones
Neoplasia - tumor
How is FLUTD diagnosed?
The initial diagnosis of FLUTD is based on the identification of signs of lower urinary tract inflammation. The clinical signs displayed by the cat are often characteristic of FLUTD. A urinalysis will confirm the presence of inflammation or infection.
What further tests are required to diagnose the cause of FLUTD?
When clinical signs are persistent or recurrent, a number of investigations may be required to differentiate idiopathic FLUTD from the other known causes of urinary tract inflammation. These diagnostic tests include:
Laboratory analysis of a urine sample
Bacterial culture of a urine sample
Blood samples to look for other evidence of urinary tract disease or other systemic diseases
Radiographs (x-rays) or ultrasound examination of the bladder and urethra
The information from these tests should help to identify a specific treatable underlying cause if present.
What is the treatment for FLUTD?
This depends on the underlying cause. For example:
Cases of idiopathic disease may respond to treatment with anti-inflammatory or analgesic or pain-relieving drugs, but it is crucial that you only use drugs specifically prescribed by your veterinarian because many human products are extremely dangerous to cats.
Bacterial infections of the lower urinary tract usually respond well to antibiotic therapy.
If a cat develops a blocked urethra, emergency treatment is required to remove the blockage, which may require flushing of the urethra while the cat is given a short-acting anesthetic. A urethral obstruction occurs almost exclusively in male cats.
If bladder stones are present, they may have to be removed surgically or, depending on their type, they may be able to be dissolved by using a special diet or dietary additive
There is no universal treatment for FLUTD. Each case has to be investigated to determine the underlying cause, and then the treatment has to be tailored to the individual cat. Sometimes despite appropriate tests and treatment clinical signs may still recur, requiring further therapy.
How can FLUTD be prevented?
It is impossible to completely prevent diseases of the lower urinary tract from occurring. However, FLUTD is more common in cats that have lower water consumption and in cats that are inactive and obese. All these factors may relate, at least in part, to the frequency with which a cat urinates. Weight control and encouraging exercise may be of some help in preventing FLUTD.
If a cat develops urinary calculi or crystals, the feeding of special diets may help prevent FLUTD.