Page 201 - Problem-Based Feline Medicine

12. The incontinent cat

Lucio John Filippich

KEY SIGNS

● Urinary incontinence.
● Urine soiling around the perineal area.
● Perineal dermatitis.

MECHANISM?
● The incontinent cat has lost voluntary control over urination and intermittently or continuously
dribbles urine. Maintenance of urinary continence in the cat depends on normal lower urinary
tract anatomy and function and an intact nervous system. Urinary incontinence results from
abnormalities of either the filling or emptying processes.
● During the filling phase (sympathetic stimulation), the body of the bladder acts as a reservoir
with flaccid walls that generate little pressure, while the outlet of the bladder is a high-resist-
ance duct preventing the passage of urine.
● During the emptying phase (parasympathetic stimulation), the roles are reversed and the body
of the bladder becomes a pump that expels urine under high pressure while the outlet of the
bladder reflexly opens and becomes a low-resistance duct.
● The two phases are functionally independent and depend on the cerebral cortex for co-ordina-
tion and voluntary control.

WHERE?
● Lower urinary tract (lower ureter, urinary bladder, urethra).
WHAT?
● Urinary incontinence in cats is uncommon. In juvenile cats, it is more likely due to a congeni-
tal abnormality (ectopic ureter); in the adult cat it is more likely neurologic in origin.
Secondary urinary tract infections are common.

193