In multiple sclerosis, the most common mechanism of urinary incontinence is detrusor:

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Multiple Choice

In multiple sclerosis, the most common mechanism of urinary incontinence is detrusor:

Detrusor overactivity is the usual mechanism behind urinary incontinence in multiple sclerosis. MS lesions disrupt inhibitory control over the bladder, so the detrusor muscle contracts involuntarily during filling. This leads to urgency and leakage—a classic urge incontinence pattern seen with a neurogenic bladder. Detrusor underactivity would cause poor bladder emptying and overflow, not the sudden leakage of urgency. Sphincter weakness tends to produce leakage with coughing or effort (stress incontinence) rather than the spontaneous urgency typical of MS. Vesical outlet obstruction is uncommon in MS and classically presents with retention rather than incontinence.

Detrusor overactivity is the usual mechanism behind urinary incontinence in multiple sclerosis. MS lesions disrupt inhibitory control over the bladder, so the detrusor muscle contracts involuntarily during filling. This leads to urgency and leakage—a classic urge incontinence pattern seen with a neurogenic bladder.

Detrusor underactivity would cause poor bladder emptying and overflow, not the sudden leakage of urgency. Sphincter weakness tends to produce leakage with coughing or effort (stress incontinence) rather than the spontaneous urgency typical of MS. Vesical outlet obstruction is uncommon in MS and classically presents with retention rather than incontinence.

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