2 - Lower Urinary Tract Symptoms

Authors: Macfarlane, Michael T.

Title: Urology, 4th Edition

Copyright 2006 Lippincott Williams & Wilkins

> Table of Contents > Part One - Chief Presentations > Chapter 2 - Lower Urinary Tract Symptoms

Chapter 2

Lower Urinary Tract Symptoms

Lower urinary tract symptoms (LUTS) are classified as storage symptoms (previously referred to as irritative symptoms) or voiding symptoms (previously referred to as obstructive symptoms). This change in terminology, recommended by the World Health Organization, can be applied to any patient with urinary symptoms, regardless of age or sex.

Storage (Irritative) Symptoms

Storage (irritative) symptoms (e.g., frequency, nocturia, urgency, incontinence, and bladder pain) are common presenting complaints that may herald several different urologic diseases. Storage symptoms tend to be the most bothersome to the patient, particularly nocturia.

Frequency describes the need to urinate more often than usual. If polyuria (large urine volume) is excluded, then the patient has a functionally reduced bladder capacity by virtue of decreased compliance, residual urine, or pain on stretching. Causes include infection, tumor, stone, outlet obstruction, neurogenic bladder, or foreign body. Frequency is best recorded in terms of how many hours between voiding.

Nocturia describes the act of awakening at night to urinate and has a pathophysiology similar to that of frequency. Ask how many times the patient awakes from sleep to urinate and how much he or she drinks before retiring. Nocturia one to two times per night is inconsequential if the patient drinks a few cups of coffee before bed.

Urgency describes the patient's sensation to urinate immediately if an accident is to be avoided. Urgency most often accompanies infection, bladder outlet obstruction (BOO), or neurogenic bladder.

Incontinence is the involuntary loss of urine and is the ultimate sign of storage failure. Incontinence is frequently associated with urgency, frequency, or nocturia and should be distinguished by the different types (see Chapter 5).

Pain with storage is generally located in the suprapubic area and is a result of bladder distention. It is distinguished from the

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more common pain with voiding referred to as dysuria, which is also a classic irritative symptom categorized as a voiding symptom [see Voiding (Obstructive) Symptoms ].

Voiding (Obstructive) Symptoms

Voiding (obstructive) symptoms include hesitancy, straining to void, poor stream, intermittency, dysuria, feeling of incomplete emptying, and terminal or postmicturition dribbling. A poor, slow, or weak stream is the complaint most directly associated with BOO. Other complaints include decreased force of stream, hesitancy in voiding, or difficulty starting the stream. Patients also complain of decreased caliber or narrowing of the stream, which may be split or interrupted. These are all symptoms of increased outlet resistance to urine flow in the urethra or bladder neck. Voiding symptoms, except for dysuria, occur primarily in males. Prostatic enlargement is the most common cause; however, other causes include urethral stricture, bladder neck contracture, and cancer of the prostate or urethra.

Dysuria describes a burning or painful sensation on urination, which is usually felt in the urethra. It is most commonly a symptom of urinary tract infection (UTI).

Differential Diagnosis

Benign Prostatic Enlargement

Benign prostatic enlargement occurs primarily in elderly males with symptoms that usually progress gradually over a long period. Patients typically present with frequency, nocturia, and a slow, weak stream secondary to benign prostatic hyperplasia (BPH). Urinalysis is often negative, peak uroflow is reduced (<10 mL/second), and a high postvoid residual urine may be noted.

Urethral Stricture

Strictures of the urethra can occur at any age. They occur more frequently in males with a history of venereal disease, trauma, or prior instrumentation.

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Infection

Infection is probably the most common cause of storage symptoms. The patient with frequency and urgency, and pyuria on urinalysis, has a UTI. Dysuria is also a common symptom of infection. History and physical examination usually provide the additional information to localize the infection (e.g., cystitis, prostatitis, urethritis).

Acute Prostatitis

Edema and swelling of the posterior urethra, which occur with acute prostatitis, can cause significant outlet obstruction. The symptoms usually improve after the infection is eradicated. In addition to the poor flow, the patient will complain of frequency, dysuria, and high fever.

Bladder Tumor

Remember that up to 30% of patients with bladder cancer will present with irritative symptoms without hematuria. This is most often due to carcinoma in situ or muscle invasive bladder cancer. Therefore, the presence of persistent irritative symptoms in an adult with negative urinalysis and culture is an indication for cystoscopy and cytologies.

Cancer of the Prostate

Prostate cancer is another disease of elderly males, with 75% of cases occurring between the ages of 60 and 85 years. Voiding symptoms often occur more rapidly than with BPH, and the digital rectal examination (DRE) will usually be positive.

Bladder Neck Contracture

In the adult, bladder neck contracture occurs as a late complication of prostate surgery. Scar formation eventually narrows the bladder neck, increasing resistance and producing recurrent symptoms of BOO.

Meatal Stenosis

Meatal stenosis is a narrowing of the urethral opening on the glans penis. It is usually a congenital anomaly and can cause significant outlet resistance in the newborn.

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Posterior Urethral Valves

Posterior urethral valves are congenital membranelike structures located in the distal prostatic urethra; they are the most common cause of BOO in male children. Diagnosis is made on voiding cystourethrography (VCUG) and cystourethroscopy.

Other (Stone, Foreign Body, Prolapsing Ureterocele)

Any foreign body or stone in the urethra or bladder can potentially obstruct the outlet. Irritation from the stone or foreign body can cause frequency and urgency. Urinalysis will usually reveal hematuria and pyuria. The diagnosis is made at cystoscopy. Rarely, a prolapsing ureterocele has been known to obstruct the bladder neck.

Neurogenic Bladder

Frequency and urgency are common symptoms of neurogenic bladder dysfunction. Association with urge incontinence or recurrent UTIs may be noted. A urodynamic investigation is indicated after infection, tumor, and outlet obstruction have been ruled out.

Overactive Bladder

Overactive bladder (OAB) is a condition characterized by a sudden, uncomfortable need to urinate with or without urine leakage usually with daytime and nighttime frequency, whose etiology cannot be clearly identified. It is primarily a diagnosis of exclusion and is managed for the most part by behavioral therapy and antimuscarinic medications.

Neurogenic Detrusor-Sphincter Dyssynergia

An uncoordinated detrusor sphincter reflex can result in significant obstruction to urine flow. This reflex is seen almost exclusively with spinal cord injury. A urodynamic evaluation is needed to confirm diagnosis.

Polyuria

Uncontrolled diabetes mellitus or diabetes insipidus can present with frequency and nocturia. Patients will report voiding large

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volumes and polydipsia. Urinalysis may show sugar on the dipstick. Patients on diuretic therapy and psychogenic water drinkers can also present with frequency and nocturia. Occasionally, patients with new onset congestive heart failure will present with nocturia. With recumbency at night, intravascular volume will be augmented by return of lower extremity edema fluid.

Pneumaturia and Fecaluria

Pneumaturia refers to the passage of air on urination, whereas fecaluria is the passage of fecal material during voiding. The passage of air or fecal matter in the urine is most commonly the result of a fistulous communication between the intestines and urinary tract, usually at the bladder or urethra. The fistula is generally the result of gastrointestinal disease most commonly diverticulitis, colon cancer, or Crohn's disease. Patients will present with irritative symptoms and UTI in addition to the complaints of pneumaturia and fecaluria. The diagnosis is confirmed by cystoscopy, cystogram, and upper and lower gastrointestinal series. Proving a fistulous tract may occasionally be difficult. Having the patient ingest granulated charcoal by mouth is sometimes helpful if the charcoal is subsequently found in the patient's urine. Another trick is to centrifuge the patient's urine after a barium study and x-ray the sediment, looking for minute amounts of barium. The treatment is surgical separation and closure of the fistula and primary resection of the intestinal disease. Pneumaturia alone may occasionally occur secondary to UTI with yeast or Escherichia coli, which ferment glucose to CO₂ and H₂O, especially in diabetics. Emphysematous cystitis may be noted in this setting.

Workup

The most valuable data in evaluating a patient who presents with LUTS are gained from the history and urinalysis.

History

Determine the onset and duration of symptoms and the presence of any associated symptoms. Attempt to quantify the patient's symptoms (e.g., How many times do you awake from sleep each night to urinate? What is the interval between successive urinations during the daytime every hour, every 2 hours, every 3

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hours? ). Quantification of LUTS in males using the International Prostate Symptom Score (see Chapter 19) is recommended. Inquire about a history of perineal or pelvic trauma and/or prior urologic instrumentation. Note any medications that can affect urination [e.g., -agonists, such as phenylephrine (Neo-Synephrine), anticholinergic medications, or antidepressants]. Ask the patient to keep a voiding diary, carefully recording on paper fluid intake and voiding for a 24- to 48-hour period. This information can frequently give great insight into the patient's problem.

Physical Examination

The physical examination is generally of little help in differentiating causes of obstruction. Prostatic enlargement on DRE suggests BPH as the cause; however, a normal-sized prostate does not rule out BPH. Palpate the lower abdomen for the presence of a full bladder. Examine the external genitalia, paying particular attention to the urethral meatus.

Urinalysis

Hematuria suggests a tumor, BPH, stone, or foreign body. Pyuria is also noted with the presence of stones or foreign bodies, in addition to infectious etiologies such as acute prostatitis. If infection is suspected, a urine culture should be obtained.

Uroflowmetry

Measuring the peak urine flow rate will give objective documentation of the severity of obstruction and can be valuable for following the progression of disease or response to treatment. Postvoid residual urine should always be determined following the uroflow test, generally by ultrasound bladder scan or urethral catheterization.

Cystourethroscopy

Visualization of the urethra and bladder is the single best method to assess BOO.