Urinary Retention

Alternative names: Ischuria, Acute Urinary Retention, Chronic Urinary Retention

Urinary retention is the inability to completely empty the bladder; Acute Urinary Retention (AUR) is the (near) complete inability to pass urine, which is a medical emergency.

Chronic Urinary Retention is a long-term inability to completely empty the bladder.

Incidence; Causes and Development; Contributing Risk Factors

Urinary retention affects men 10 times more frequently than women, and is most common in men aged over 70.

There are many possible causes of urinary retention, including:

• Constriction of the urethra due to injury
• Constriction of the urethra due to sexually-transmitted disease.  Gonorrhea creates numerous strictures, leading to a "string of beads" appearance; chlamydia usually causes a single stricture.
• Bladder Stones
• Bladder Cancer
• Fecal Impaction
• Gastrointestinal Cancer: Biliary, Pancreatic, Small Bowel, Colon, Rectal, Anal
• Retroperitoneal Tumor (very rare)
• Foreign body in the urethra
• Urethral stones (stones that have become stuck after leaving the bladder)
• Schistosomiasis (parasitic worm infection) of the urinary tract
• Cystitis (bladder inflammation)
• Herpes Simplex Virus (HSV) or Varicella-Zoster Virus (VZV) infection
• Periurethral Abscess
• Side-effects of antipsychotics, antidepressants, anticholinergics, amphetamines, opioids, anesthetics, NSAIDs, COX-2 inhibitors, antihistamines, alcohol, and other pharmaceutical drugs
• Conditions affecting the autonomic or peripheral nerve, including Autonomic Neuropathy, Diabetes Mellitus, Guillain-Barré Syndrome, Pernicious Anemia, Poliomyelitis, Spinal cord injury, Syphilitic infection of the spinal cord
• Conditions affecting the brain, including Cardiovascular Disease, Multiple Sclerosis, Brain Tumor, Normal Pressure Hydrocephalus, Parkinson's Disease
• Conditions affecting the spinal cord, including Intervertebral Disc Disease, Spina Bifida, Multiple Sclerosis, Spinal Cord Hematoma or Abscess, Spinal Cord Trauma, Spinal Stenosis, Spinovascular Disease, Transverse Myelitis, Spinal Tumors, Cauda Equina Syndrome
• Consequences of medical treatment, for example scarring of the bladder from removing catheters
• Psychogenic causes such as fear associated with urination, or being unable to urinate around strangers (Paruresis)

• (In men)

  • Benign Prostatic Hyperplasia (BPH)
  • Prostate Cancer
  • Erectile dysfunction rings (penile constrictive band, erection ring, or penile ring)
  • Prostatitis (the most common cause in young males, usually acquired from sexual intercourse)
  • Prostatic Abscess
  • Circumcision, foreskin swelling, or inability to retract
  • Penile trauma, including fracture or laceration

• (In women)

  • Prolapse

    • Anterior Prolapse
    • Posterior Prolapse
    • Uterine Prolapse

  • Pelvic Mass

    • Gynecological Cancer: Cervical, Ovarian, Uterine, Endometrial, Vulvar, or Vaginal
    • Uterine Fibroids
    • Ovarian Cysts
  • Vaginal inflammation due to bacterial or yeast infection, vaginal lichen planus, vaginal lichen sclerosus, vaginal pemphigus)
  • History of sexual abuse
  • Complications during birth

Benign Prostatic Hyperplasia (BPH) is by far the most common cause among men.

Risk factors for urinary retention include:

• Alcohol consumption
• Recent surgery
• History of neurological conditions
• Urinary tract infection (UTI)
• Constipation
• Excess fluid intake
• Exposure to cold
• Prolonged travel
• Pharmaceutical drug use

Signs and Symptoms

The main symptoms of Acute Urinary Retention include:

• Pain (caused by a distended bladder)
• Weak urinary stream with intermittent flow, or non-passage of urine
• A delay between trying to urinate and urine flow beginning
• Tender enlarged bladder
• Symptoms of conditions that can cause it, for example fever, weight loss, weakness, loss of sensation, genital infection, long-term constipation, or inflammation
• (As the bladder becomes full:) Incontinence, nocturia, frequent need to urinate

In cases of Chronic Urinary Retention there are often no symptoms: the patient may not become aware of it until a secondary condition such as urinary incontinence or a urinary tract infection develops.  If symptoms are present, they may include:

• Increased urinary frequency
• Feeling the urgent need to pass urine, but without success
• Difficulty passing urine
• A weak and/or interrupted urine stream
• Feeling the need to urinate right after urinating
• Constant, mild discomfort in the lower abdomen

Diagnosis and Tests

Tests that are commonly performed are:

• Midstream Specimen of Urine (MSU) test
• Blood tests, including: Complete Blood Count (CBC), Urea and Electrolytes (U+E), Creatinine, Estimated Glomerular Filtration Rate (eGFR), Blood Glucose
• Imaging studies, including: Ultrasound, CT Scan, MRI/CT brain scan, Spinal MRI, Cystoscopy

Treatment and Prevention

The most urgent and necessary procedure is immediate and complete emptying of the bladder, normally involving catheterization.  Beyond that, the underlying condition needs to be treated.

Chronic urinary retention may require surgical intervention.  Types of surgery include urethral dilatation, installing urethral stents, internal urethrotomy, removal of tumors or other obstructions, prostate surgery for men, and cystocele or rectocele repair for women.

Prevention of urinary retention in men with Benign Prostatic Hyperplasia involves long-term medical treatment with 5-alpha reductase inhibitors, with or without alpha-blockers.

Diet and lifestyle changes that prevent constipation will also help to prevent urinary retention.  For women with genitourinary prolapse, pelvic floor exercises can help.

Prognosis; Complications

Some cases of urinary retention, for example when caused by general anesthetic, resolve quickly and without long-term problems.

Other cases resolve when the underlying cause, for example BPH, has been corrected.

Sometimes the cause cannot be treated, and in such cases it is necessary, on an ongoing basis, to regularly insert a catheter into the bladder in order to void urine.  This would normally be done every 3-4 hours, 4-6 times per day.

Possible post-catheterization complications include Urinary Tract Infection (UTI); acute renal failure; excess urine production, possibly resulting in electrolyte depletion; blood in the urine (this usually goes away by itself).

Acute urine retention (resulting in complete anuria – failure to produce any urine) is a medical emergency.  If left untreated, the bladder can stretch to the point of tearing, and then release its contents into the abdominal cavity.  Increased bladder pressure can also force urine back up the ureters into the kidneys, leading to hydronephrosis (swelling of the kidneys), pyonephrosis (kidney infection), kidney failure, chronic kidney disease due to scarring, or sepsis.

The normal capacity of the bladder is 400-600ml; the largest amount of urine drained from the bladder of a patient suffering from urinary retention was 6,000ml (6 liters).