Feline lower urinary tract disease

Feline lower urinary tract disease (FLUTD) is a generic category term to describe any disorder affecting the bladder or urethra of cats.

Less common causes are urolithiasis, and urethral plugs which usually result when an attack of feline idiopathic cystitis is not self-limiting and escalates into a blockage of the bladder (i.e. obstructive FIC).

The rarest forms of FLUTD for any age/sex cohort include anatomic defects, behavioural disorders and neoplasia.

Feline idiopathic cystitis (FIC) is by far the most common form of FLUTD in young to middle-aged cats.

It is a disease whose cause is not fully understood but is thought to be related to stress events and a cat's pre-disposition to anxiety, as well as certain lifestyle choices (e.g. a dry food diet, no access to outdoor space).

The sensory neurons are composed of unmyelinated C-fibers (group C nerve fiber), and when stimulated cause pelvic pain.

Prolonged stimulation of the C-fibers causes chronic inflammation that is maintained through the release of the neurotransmitter substance P. This increases the vascular permeability of the bladder, allowing red blood cells and lymphocytes to enter.

However, they can pose the risk of urethral obstruction if they accumulate in the bladder and are allowed to clump together to form larger stones (i.e. uroliths) which then become lodged in the urethra.

Alternatively, they can coalesce with inflammatory bladder debris (or "matrix") to form obstructive § urethral plugs following an attack of feline cystitis (see below).

Commercial feline foods limit the amount of magnesium and add acidifiers such as DL-Methionine to increase urine acidity, thereby reducing the likelihood of struvite accumulation.

[7] Increase in hydration, principally via the feeding of wet food should be the first and most important preventative technique to dissolve crystals and flush them out before they become a possible source of obstruction.

However ordinary wet food with high moisture content and rich in animal protein can be just as effective in many cases as it keeps the urine mildly acidic and dilute, both of which militate against struvite formation.

These non-obstructive episodes usually resolve themselves in a week with good hydration, analgesia and/or anti-inflammatory medication together with anti-spasm drugs such as prazosin.

Owners with outdoor cats may not be able to observe the symptoms associated with litter box use and should watch for unusual behavioural changes.

The cat may seek seclusion, stop eating and drinking, begin to vomit, and become lethargic and eventually comatose as toxins accumulate in the bloodstream.

Cats susceptible to repeated attacks of this disorder may require surgery, such as the removal of the penis (urethrostomy) to prevent its blockage although this a last line of treatment.

Unlike in humans, bacterial infection (UTI) is a very rare cause of FLUTD, accounting for 1–5% of cats younger than 10 years.

Since indoor cats are an at-risk cohort, supervised outdoor play for restricted periods will increase stimulation and reduce stress.

Placing scratch posts or raised walkways where they can retreat and hide increases their sense of security and familiarity of the area.

The use of play time and toys to increase their exercise levels is advised as obese and sedentary cats seem to be at higher risk for the development of LUTD and FIC.