Urinary frequency is the need to urinate many times during the day, at night (nocturia), or both but in normal or less-than-normal volumes. Frequency may be accompanied by a sensation of an urgent need to void (urinary urgency). Urinary frequency is distinguished from polyuria, which is increased urine output of > 3 L/day.
Pathophysiology of Urinary Frequency
Urinary frequency usually results from disorders of the lower genitourinary tract. Inflammation of the bladder, urethra, or both causes a sensation of the need to urinate. However, this sensation is not relieved by emptying the bladder, so once the bladder is emptied, patients continue trying to void but pass only small volumes of urine.
Etiology of Urinary Frequency
There are many causes of urinary frequency (see table Some Causes of Urinary Frequency), but the most common include
Urinary tract infections (UTIs)
Evaluation of Urinary Frequency
History
History of present illness should first ask about the amounts of fluid consumed and voided to distinguish between urinary frequency and polyuria. If urinary frequency is present, patients are asked about acuity of onset, presence or absence of irritative symptoms (eg, irritation, urgency, dysuria), obstructive symptoms (eg, hesitancy, poor flow, sensation of incomplete voiding, nocturia), and recent sexual contacts.
Review of systems should cover symptoms suggestive of a cause, including fever, flank or groin pain, and hematuria (infection); missed menses, breast swelling, and morning sickness (pregnancy); and arthritis and conjunctivitis (reactive arthritis).
Past medical history should ask about known causes, including prostate disease and previous pelvic radiation therapy or surgeries. Drugs and diet are reviewed for the use of agents that increase urine output (eg, diuretics, alcohol, caffeinated beverages).
Physical examination
Examination focuses on the genitourinary system.
Any urethral discharge or any lesions consistent with sexually transmitted infections are noted. Rectal examination in men should note the size and consistency of the prostate and rectal tone; pelvic examination in women should note the presence of any cystocele. Patients should be instructed to cough while the urethra is observed for signs of urinary leakage.
The costovertebral angle should be palpated for tenderness, and the abdominal examination should note the presence of any masses or suprapubic tenderness.
Neurologic examination should test for lower-extremity weakness and loss of sensation.
Red flags
The following findings are of particular concern:
Lower-extremity weakness or signs of spinal cord damage (eg, loss of sensation at a segmental level, loss of anal sphincter tone and anal wink reflex)
Fever and back pain
Interpretation of findings
Dysuria suggests frequency is due to urinary tract infection (UTI) or calculi. Prior pelvic surgery suggests incontinence. Weak urine stream, nocturia, or both suggests benign prostatic hyperplasia (BPH). Urinary frequency in an otherwise healthy young patient may be due to excessive intake of alcohol or caffeinated beverages. Gross hematuria suggests UTI and calculi in younger patients and genitourinary cancer in older patients.
Testing
All patients require urinalysis and culture, which are easily done and can detect infection and hematuria.
Cytoscopy, cystometry, and urethrography can be done to diagnose cystitis, bladder outlet obstruction, and cystocele. Prostate-specific antigen level determination, ultrasonography, and prostate biopsy may be required, especially in older men, to differentiate BPH from prostate cancer.
Treatment of Urinary Frequency
Treatment varies by cause.
Geriatrics Essentials: Urinary Frequency
Urinary frequency in older men is often caused by bladder neck obstruction secondary to prostate enlargement or cancer. These patients usually require an ultrasonographic bladder scan to determine postvoid residual urine volume. Urinary tract infection or use of diuretics may be a cause in both sexes.
Key Points
UTI is the most common cause in children and women.
Prostate disease is a common cause in men aged > 50 years.
