Urinary incontinence pathophysiology
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Urinary incontinence in adults
Continence and micturition involve a balance between outlet (urethra) and bladder detrusor muscle activity. Lower urinary tract function is often divided into filling and voiding phases. Normally as the bladder fills the detrusor is compliant - stretching and increasing the volume it holds - without any unpleasant sensation and the outlet is closed. At a socially acceptable time and place to void the bladder (detrusor) contracts and the outlet relaxes and flow ensues. Any perturbation in that balance can lead to voiding dysfunction or incontinence. Abnormal detrusor muscle activity or hypersensitivity of the bladder can lead to urge incontinence. An incompetent outlet can lead to stress incontinence. A bladder that cannot contract may lead to overflow incontinence.
Urinary incontinence in children
Urination, or voiding, is a complex activity. The bladder is a balloon like muscle that lies in the lowest part of the abdomen. The bladder stores urine, then releases it through the urethra, the canal that carries urine to the outside of the body. Controlling this activity involves nerves, muscles, the spinal cord, and the brain.
The bladder is made of two types of muscles: the detrusor, a muscular sac that stores urine and squeezes to empty, and the sphincter, a circular group of muscles at the bottom or neck of the bladder that automatically stay contracted to hold the urine in and automatically relax when the detrusor contracts to let the urine into the urethra. A third group of muscles below the bladder (pelvic floor muscles) can contract to keep urine back.
A baby's bladder fills to a set point, then automatically contracts and empties. As the child gets older, the nervous system develops. The child's brain begins to get messages from the filling bladder and begins to send messages to the bladder to keep it from automatically emptying until the child decides it is the time and place to void.
Failures in this control mechanism result in incontinence. Reasons for this failure range from the simple to the complex.
Incontinence happens less often after age 5: About 10 percent of 5-year-olds, 5 percent of 10-year-olds, and 1 percent of 18-year-olds experience episodes of incontinence. It is twice as common in girls as in boys.
Incontinence is also called enuresis
- Primary enuresis refers to wetting in a person who has never been dry for at least 6 months.
- Secondary enuresis refers to wetting that begins after at least 6 months of dryness.
- Nocturnal enuresis refers to wetting that usually occurs during sleep (nighttime incontinence).
- Diurnal enuresis refers to wetting when awake (daytime incontinence).
Points to remember
- Urinary incontinence in children is common.
- Nighttime wetting occurs more commonly in boys.
- Daytime Wetting is more common in girls.
- After age 5, incontinence disappears naturally at a rate of 15 percent of cases per year.
- Treatments include waiting, dietary modification, moisture alarms, medications, and bladder training.
- ↑ "pdfs.semanticscholar.org" (PDF).
- ↑ Brown JS, Bradley CS, Subak LL, Richter HE, Kraus SR, Brubaker L, Lin F, Vittinghoff E, Grady D (May 2006). "The sensitivity and specificity of a simple test to distinguish between urge and stress urinary incontinence". Ann. Intern. Med. 144 (10): 715–23. PMC 1557357. PMID 16702587.
- ↑ Videla FL, Wall LL (June 1998). "Stress incontinence diagnosed without multichannel urodynamic studies". Obstet Gynecol. 91 (6): 965–8. PMID 9611005.
- ↑ DuBeau CE, Kuchel GA, Johnson T, Palmer MH, Wagg A (2010). "Incontinence in the frail elderly: report from the 4th International Consultation on Incontinence". Neurourol. Urodyn. 29 (1): 165–78. doi:10.1002/nau.20842. PMID 20025027.
- ↑ "Diagnosis of Urinary Incontinence - American Family Physician".
- ↑ Frank C, Szlanta A (November 2010). "Office management of urinary incontinence among older patients". Can Fam Physician. 56 (11): 1115–20. PMC 2980426. PMID 21075990.
- ↑ Imam KA (2004). "The role of the primary care physician in the management of bladder dysfunction". Rev Urol. 6 Suppl 1: S38–44. PMC 1472846. PMID 16985854.