Urinary Incontinence

Urinary Incontinence

General. Defined as involuntary loss of urine.

Causes. Causes of transient incontinence include delirium, infection, atrophic vaginitis or urethritis, drugs, including sedatives, hypnotics, diuretics, opiates, calcium-channel blockers, anticholinergics (antidepressants, antihistamines), decongestants, and others. Less common causes include depression, excess urine production (diabetes, diabetes insipidus), restricted mobility (i.e., patient cannot get to the bathroom), and stool impaction.

Types of Incontinence and Their Specific Causes.

Urge incontinence. Involuntary loss of urine associated with a sudden urge and desire to void. Associated with detrusor overactivity. Causes include neurologic disorders (such as stroke, multiple sclerosis), urinary tract infections, and uroepithelial cancer.

Stress incontinence. Involuntary loss of urine during coughing, sneezing, laughing, or other increases in intra-abdominal pressure. Most commonly seen in women after middle age (especially with repeated pregnancies and vaginal deliveries), stress incontinence is often a result of weakness of the pelvic floor and poor support of the vesicourethral sphincteric unit. Another cause is intrinsic urethral sphincter weakness such as that from myelomeningocele, epispadias, prostatectomy, trauma, radiation, or sacral cord lesion.

Overflow incontinence. Involuntary loss of urine associated with overdistension of the bladder. May have frequent dribbling or present as urge or stress incontinence. May be attributable to underactive bladder, bladder outlet obstruction (such as tumor, prostatic hypertrophy), drugs (such as diuretics), fecal impaction, diabetic neuropathy, or vitamin B12 deficiency.

Functional incontinence. Immobility, cognitive deficits, paraplegia, or poor bladder compliance.


Evaluation. Confirm urinary incontinence and identify factors that might contribute:

History, including medications and provoking factors.
Physical, including abdominal exam, pelvic exam, rectal exam, sensation in the rectal and perineal area, edema, drugs.
Do stress testing. Have patient cough or sneeze.
UA and microscopic examination of urine. Urine culture, if warranted.
Check postvoid residual; will be increased by outlet obstruction, neurogenic bladder, etc.
Follow timing of incontinence. Observe patient urinating and watch for signs of straining, etc.
Cystometry with flow rates, etc., may be needed if cause clinically inapparent.

Treatment. Set goals and scoring system ahead of time. Most patients will respond to behavioral techniques. Most require structured input from nursing personnel.

Bladder training. Need education, scheduled voiding, and rewards. Must inhibit urinating until a set time, and this set amount of time should be progressively increased. Start at 2 to 3 hours and progress upward. 12% may become entirely continent, and 75% may have a 50% reduction in incontinent episodes. Works best in urge incontinence but also may help stress incontinence.
Habit training. Teach patients to void when they normally would (e.g., morning, before bed, after meals).
Prompted voiding. Especially good in cognitively impaired individuals. Reduced incontinent episodes by about 50%.
Pelvic floor exercises (Kegel exercises). Especially useful in stress incontinence; 16% cure rate and 54% improve.
Intermittent catheterization may also be used.
Drugs.
For urge incontinence, bladder spasms, detrusor instability. Oxybutynin (Ditropan, Ditropan XL), tolterodine (Detrol) (low incidence of dry mouth). Tolterodine is expensive and no more efficacious than is oxybutynin. Second-line drugs include propantheline (may affect smooth muscle in the small bowel), flavoxate (Urispas), hyoscyamine sulfate (Levsin, Levsinex), and tricyclic antidepressants.
For stress incontinence. Agents that increase bladder outlet resistance (e.g., pseudoephedrine).
For men. Treating obstructive prostatic symptoms may help (see section on BPH).
In women. Estrogen may be useful for stress and urge incontinence (start with half applicator of estrogen cream every other day and increase to 1 applicator QHS if needed or used orally as for postmenopausal use). The efficacy of estrogen has been questioned by double-blind studies. May need surgical repair.
Newer products include Introl bladder neck support prosthesis (similar to pessary and assists women with incontinence secondary to urethral hypermobility), Reliance urinary control insert, magnetic innervation technology.

A 55-year-old woman has had profuse watery diarrhea for 3 months. Laboratory studies of fecal water show the following:

Sodium: 39 mmol/L
Potassium: 96 mmol/L
Chloride: 15 mmol/L
Bicarbonate: 40 mmol/L
Osmolality: 270 mosmol/kg H2O (serum osmolality: 280 mosmol/kg H2O)

The most likely diagnosis is


A villous adenoma
B lactose intolerance
C laxative abuse
D pancreatic insufficiency
E nontropical sprue

The answer is A
In the case described, the osmolality of fecal water is approximately equal to serum osmolality. Furthermore, there is no osmotic 'gap' in the fecal water; the osmolality of the fecal water can be accounted for by the stool electrolyte composition: = [2 (39 + 96)] = 270. A villous adenoma of the colon typically produces a secretory diarrhea. Lactose intolerance, nontropical sprue, and excessive use of milk of magnesia produce osmotic diarrheas with osmotic 'gaps' caused by lactose, carbohydrates, and magnesium, respectively. Pancreatic insufficiency causes steatorrhea, not watery diarrhea.