Handbook of Genetic Counseling/Incontinence
Incontinence
General Information
edit- Refers to inability to retain urine in bladder
- Due to neurologic or mechanical disorder
- Normal bladder function
- Detrusor muscle provides propulsive force for emptying bladder
- Smooth muscle under parasympathetic autonomic control
- Involves pelvic nerves from sacral spinal cord
- Layer of smooth muscle of trigonal part of bladder acts as involuntary internal sphincter
- Helps prevent incontinence even if no voluntary control
- Innervated by motor fibers from T11 to L2
- External sphincter and perineal muscles under voluntary control of pudendal nerves
- Sensory tracts of pain, temperature, and distention pass from bladder to pelvic nerves to sacral spine to medulla of brain to cortical centers
- Detrusor muscle provides propulsive force for emptying bladder
- Infants and adults with spinal damage above S2 urinate spontaneously when bladder fills
Causes of Incontinence
edit- Detrusor instability
- Bladder prone to uncontrollable contractions
- Caused by damage to inhibitory neural pathways (70% of incontinence among elderly)
- Cerbrovascualr accidents
- Alzheimer's disease
- Neoplasia
- Hydrocephalus (?maybe?)
- Could also be caused by bladder or pelvic infection or tumor, fecal impaction, uterine prolapse, and prostate hypertrophy
- May be treated with Imipramine or calcium channel blockers
- Stress incontinence
- Common in postmenopausal parous women
- Structures of female urethra atrophy when deprived of estrogen
- Pass urine under increased abdominal pressure during coughing, sneezing, climbing stairs
- Physical activity may result in small amount of urine escaping
- Mechanical incontinence
- Congenital anomalies, extrophy of bladder, patent urachus, and ectopic ureteral openings
- Correctable by surgery only
- May also be caused by prostate surgery, pelvic surgery, or irradiation of uterus or rectum
- Overflow or paradoxical incontinence
- Large residual volumes of urine
- Secondary to obstruction at bladder neck or urethra, or neurologic damage
- May occur in diseases that produce autonomic peripheral neuropathy
- Diabetes mellitus, uremia, hypothyroidism, chronic alcoholism, Guillain-Barre syndrome, collagen vascular diseases, and toxic neuropathy caused by carcinomas
- Also may be due to prolonged distension of bladder
- May be treated surgically if obstruction or with bethanechol chloride
- Psychogenic and functional incontinence
- Occurs in children and some adults
- May be to draw attention to themselves
- May have psychological cause from abuse or other traumatic experiences
- Enuresis
- Involuntary passage of urine at night during sleep
- Considered normal under age of 2 years as neurological controls are still developing
- Approximately 10% of children have some degree of enuresis beyond age of three
- May be due to delay in maturation of bladder control
- May be familial
- Usually ceases by age of puberty unless disease interferes
- Urinary tract infections, obstructive lesions, neurovesical dysfunction, and polyuric conditions that overload the bladder
- Usually incontinent during the day also if one of these conditions
- Approximately 10% of children have some degree of enuresis beyond age of three
Reference
edit- "Dysuria, Frequency and Urgency, Incontinence, and Enuresis." Principles of Internal Medicine (1994): 240-241.
Notes
editThe information in this outline was last updated in 2002.