Urinary Incontinence

Urinary incontinence is the involuntary leakage of urine due to weakness or loss of associated sphincter musculature (i.e. the pelvic floor muscles). Spontaneous voiding occurs with a bladder volume of 300 mL-400 mL. Incontinence can vary from a slight loss of urine after sneezing, coughing, or laughing to being completely unable to control urination. Urinary incontinence is a symptom, not a disease, of an underlying infection or as a result of medications or increased fluid intake. Urinary tract infections are often associated with mild urinary incontinence. Constipation can cause urinary incontinence due to intraabdominal pressure from a large fecal burden.

Important questions to ask a patient (or caregiver) presenting for evaluation of urinary incontinence include:

• Are you experiencing any hematuria (blood in the urine)? Dysuria (pain with urination)? Frequency? Urgency?
• Are you experiencing any urinary retention when you go to the bathroom?
• What amount of fluids are you drinking in the course of a day? Has decreasing fluid intake helped? How much caffeine do you drink?
• Were you recently started on any new medications?
• How many pregnancies and vaginal deliveries have you had? When was your last visit to ob/gyn? When was your last pelvic exam? (Female patients only.)
• Are you experiencing constipation?
• Are you able to make it to the bathroom on time?
• Has this incontinence affected your social activities?

As part of the physical exam, in addition to heart, lungs, and abdomen assessments, one should also evaluate costovertebral tenderness and suprapubic pressure.

There are five types of urinary incontinence to consider:

1. Stress incontinence occurs as a result of detrusor muscle weakness. It most commonly occurs in women who have had multiple vaginal deliveries. Symptoms are precipitated by coughing, sneezing, laughing, or lifting. Kegel exercises (named after gynecologist Arnold Kegel, MD) can be done as a type of non-pharmacologic treatment and involve repeatedly contracting and relaxing the muscles of the pelvic floor in order to strengthen these muscles.
2. Urge incontinence is characterized by increased frequency of urination associated with an intense urge followed by involuntary loss of urine. Colloquially, urge incontinence is sometimes called “overactive bladder”. The causes of urge incontinence can be due to drinks or medications. For example, caffeine, alcohol, and diuretics can promote frequent urination. Nocturia is associated with sleep disruption that prompts patients to wake from sleep to urinate.
3. Overflow incontinence is associated with a bladder that does not entirely empty. Patients with urinary retention will often experience overflow incontinence which may or may not have a neurological (i.e. neurogenic bladder) component. Men with benign prostatic hyperplasia may experience overflow incontinence due to the large prostate preventing the bladder from completely emptying. Anticholinergic side effects of medication may also cause urinary retention, leading to overflow incontinence. Clinically, urinary retention can be assessed by a post-void residual (either by catheterization or bladder scan). In practice, post-void residual urine is considered abnormal if greater than 200 mL-250 mL.
4. Functional incontinence is defined as the functional inability to physically get to the toilet which results in the involuntary loss of urine, for example, in a bedbound patient.
5. Mixed incontinence is the simultaneous presence of two or more incontinence types; in men mixed incontinence typically consists of urge incontinence and overflow incontinence (due to prostatic enlargement) whereas in women it typically consists of stress incontinence and urge incontinence.

Treatment of urinary incontinence should involve keeping a bladder diary, scheduling toileting, and tracking fluid intake. Attempt non-pharmacologic management before resorting to medications. Oxybutynin and tolterodine are medications which exert direct antispasmodic effect on smooth muscle and inhibit the muscarinic action of acetylcholine on smooth muscle. Use anticholinergic medications with caution in geriatric patients! Medications should be employed only after non-pharmacologic methods fail. For female patients, consider referral to an ob/gyn for a pelvic exam (if the primary care physician does not perform this exam). For male patients, consider referral to urology for benign prostatic hyperplasia if medications such as tamsulosin and finasteride offer no improvement of symptoms.

Interpreting a Urinalysis and Urine Culture/Sensitivity

A urinalysis with culture/sensitivity should be obtained with the presence of urinary incontinence symptoms to determine if an underlying urinary tract infection (UTI) may be present. Specifically, the presence of leukocyte esterase or nitrites on a urinalysis may indicate the presence of a UTI. The most common organism implicated in urinary tract infections is Escherichia coli (E. coli) due to the proximity to the lower GI tract, though other organisms are often seen. E. coli is a Gram-negative rod which produces nitrites as is Klebsiella pneumoniae. In the event that 1) symptoms are present and 2) leukocyte esterase and/or nitrites are present on urinalysis and a urine culture is performed, treatment should only be initiated if the bacteria colony count is greater than 100,000 colony forming units (CFUs). However, a urinalysis should only be obtained if symptoms are present, as asymptomatic bacteriuria is common and does not respond to antibiotic treatment due to bacterial colonization of the genitourinary (GU) tract, regardless of the number of colony forming units. Likewise, the presence of epithelial casts on a urinalysis will indicate that the collection of the urine was not done in a sterile manner and the results should not be considered reliable.

An example of a urinalysis:

An example of a urine culture and sensitivity:

Colony count: >100,000 CFU Gram-negative rods
Organism identification: Klebsiella pneumonia

The minimum inhibitory concentration (MIC) is the lowest concentration (in μg/mL) of an antibiotic that inhibits the growth of a given strain of bacteria. Because a lower MIC value indicates that less of the drug is required in order to inhibit growth of the organism, drugs with lower MIC scores are more effective antimicrobial agents. For example, if the above urine culture were to be used to determine appropriate treatment, ciprofloxacin would be the most appropriate treatment. The sensitivity is listed as S (for sensitive), I (for intermediate), or R (for resistant.)

Review Questions

1. A 69-year-old female presents to her primary care physician complaining of “increased urinating accidents”. She denies urgency, frequency, or dysuria. Her symptoms have worsened in the last three months. She has had four children, all delivered vaginally. She has “accidents” when she laughs, coughs, or sneezes. She has tried cutting back on her fluid intake and this has not helped. She takes amlodipine for hypertension and atorvastatin for hyperlipidemia, but otherwise takes no medications and has no other medical problems. Her vital signs are stable and she is afebrile. Her physical exam is unremarkable. What type of urinary incontinence does this patient describe?

A. Urge incontinence
B. Overflow incontinence (Neurogenic bladder)
C. Functional incontinence
D. Stress incontinence
E. Mixed incontinence

2. As part of the workup for this patient, her primary care physician orders a urinalysis with culture and sensitivity (U/A C&S). The result is shown above in Tables 8.1 and 8.2. Which of the following medications is best to treat the patient based on the results of this U/A C&S?

A. Ciprofloxacin
B. Nitrofurantoin
C. Tetracycline
D. Trimethoprim-sulfamethoxazole
E. No treatment is indicated for this patient.

3. An 86-year-old female presents for follow up with her primary care physician for increased urinary urgency and frequency. She denies any hematuria or dysuria. Her medical history is notable for stress incontinence following the births of her four children. Two were delivered vaginally and two were delivered by Caesarian section. She had success with performing Kegel exercises with treating her symptoms until one month ago with the onset of increased frequency and urgency. She is urinating every two hours all day long and all night long. She has begun wearing protective underwear and pads. Her social schedule has been severely impacted as she is afraid to leave the house. She has decreased her oral intake to less than 24 fluid ounces of water per day. She drinks no other beverages. She takes amlodipine for hypertension but has no other significant medical history and takes no additional medications. Her vital signs and physical exam are unremarkable. Her primary care physician ordered a urinalysis two weeks ago which was unremarkable. Which of the following is the most appropriate next step in the management of this patient?

A. Start oxybutynin
B. Scheduled toileting
C. Repeat urinalysis
D. Start antibiotic therapy
E. Refer to ob/gyn

Answers to Review Questions

1. D
2. E
3. E