What are the other Names for this Condition? (Also known as/Synonyms)

• Acute Bilateral Obstructive Uropathy
• Acute Unilateral Obstructive Uropathy
• Acute Urinary Tract Obstruction

What is Acute Obstructive Uropathy? (Definition/Background Information)

• Acute Obstructive Uropathy is a condition in which there is a sudden blockage at any site in the urinary tract (at the kidneys, ureters, bladder outlet, or urethra), resulting in an obstruction to the flow of urine. The obstruction can occur in one urinary tract or may involve both the tracts simultaneously
• The most common cause for Acute Obstructive Uropathy, which generally affects men, is benign prostatic hyperplasia (BPH), a condition in which there is enlargement of the prostate gland. Other possible causes may include stones and cancers of the urinary tract (kidneys, ureters, bladder and urethra)
• Acute Obstructive Uropathy can lead to a significant and sudden drop in urine output, pain in the upper and lower abdomen or back, nausea, vomiting, and confusion. The condition may be diagnosed through ultrasound scan of the kidneys and bladder, abdominal CT scan, and various blood tests to check the kidney function
• Acute renal failure (ARF), a significant complication of Acute Obstructive Uropathy can be potentially avoided by prompt diagnosis and treatment. Otherwise, it may progress to chronic renal failure, which may require dialysis or renal transplant
• Bladder cauterization is used to treat the condition, to enable the flow of urine out of the body. However, the underlying cause of Acute Obstructive Uropathy needs to be addressed suitably, in order to prevent its recurrence

Who gets Acute Obstructive Uropathy? (Age and Sex Distribution)

• Acute Obstructive Uropathy can affect any individual of any age group, but it is more common in older adults due to the increased prevalence (commonness) of tumors, surgeries, and other medical complications in this age group
• The condition is also more common in males than females, due to the fact that the urethra (tube connecting bladder to the exterior) is longer in males, and also because prostate enlargement, one of the important causative factors of Acute Obstructive Uropathy, is a common health problem in older males
• This urinary tract disorder is seen worldwide, with no racial or ethnic predilection being observed

What are the Risk Factors for Acute Obstructive Uropathy? (Predisposing Factors)

The risk factors associated with Acute Obstructive Uropathy include:

• Elderly male: Due to an increased occurrence of benign prostatic enlargement in this age group
• Presence of kidney or ureteral  stones that remained untreated
• Urinary bladder stones
• Cancers of the urinary tract (including the kidney, ureter, and bladder)
• Presence of cystocele in women; cystocele is the bulging of bladder into the vagina
• Presence of rectocele in women; rectocele is the bulging of rectum into the vagina

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Acute Obstructive Uropathy? (Etiology)

Acute Obstructive Uropathy commonly occurs due to underlying causes that affect the flow of urine through the urinary tract.

• Urine forms in the kidneys and then it passes through the ureters (tubes connecting the kidneys to the urinary bladder) to the urinary bladder. Urine gets stored in the urinary bladder and when it reaches a certain amount, an individual feels the urge to pass urine
• The urethra is a small tube which connects the bladder to the outside of the body and is responsible for draining the urine out of the body. Any sudden interruption in the above drainage system of the urine results in Acute Obstructive Uropathy

Common causes of Acute Obstructive Uropathy may include:

• Benign enlargement of prostate in males
• Prostate cancer in males
• Cancers of uterus and cervix in females
• The presence of stones in the kidneys, ureters, urinary bladder, and urethra
• Presence of blood clot in the urinary tract
• Cancers of the kidney, ureter, and bladder
• Any trauma to the urinary tract
• Fibrosis or cancer in the retroperitoneum (the area present behind the abdomen): The presence of any mass, such as cancer or fibrosis, in this region may affect the urine flow through the ureters
• Urethral stricture: Narrowing of the urethra, typically resulting from previous surgeries or recurrent infections

What are the Signs and Symptoms of Acute Obstructive Uropathy?

The signs and symptoms of Acute Obstructive Uropathy may include:

• Decreased or absent urine output/volume (<10ml per day)
• Blood in the urine
• Abdominal or flank (upper abdomen or back) pain; the pain may be absent or minimal during the initial stages
• Lower abdominal pain
• Nausea, vomiting
• Altered perception (sensorium) or confusion, especially seen in elderly adults

How is Acute Obstructive Uropathy Diagnosed?

The following procedures may be used to diagnose Acute Obstructive Uropathy:

• Thorough evaluation of the individual’s medical history and a complete physical examination of the skin, heart, abdomen, rectum, and vagina
• During history taking, the physician may want to know the following:
  • When the symptoms began and whether they are becoming worse
  • List of prescription and over-the-counter medications currently being taken
  • One’s personal and family history of kidney disease, stones, prostate-related problems, etc.          
• The physical examination may reveal the following:
  • Enlarged bladder
  • Enlarged prostate
  • Mass (tumor) of the kidney, prostate, and cervix
  • Flank tenderness
  • Increase in blood pressure           
  • Abnormal sounds from the lungs (also called rales), due to excess accumulation of fluid in the body
• Urgent catheterization of the bladder is done for immediate relief. During this process, the diagnosis can also be confirmed
• Ultrasound imaging of the kidneys and bladder is the preferred test for detecting urinary tract obstruction. When an ultrasound scan is inconclusive, a CT or MRI scan of the abdomen and pelvis may be used
• Intravenous pyelogram (imaging of kidneys done after injecting a contrast dye that shows swelling of kidneys and urinary tract) is an alternate test; but, this test is rarely performed
• Laboratory tests to find the cause and monitor Acute Obstructive Uropathy include:
  • Blood urea nitrogen
  • Serum creatinine ratio
  • Creatinine clearance
  • Serum potassium and other electrolytes
  • Fractional excretion of sodium (FENa)           
  • Urine sodium and osmolality
• Other tests depending on the history and physical examination findings
• ECG (electrocardiogram) may also be taken, especially to monitor electrolyte imbalances that may cause abnormal heart rhythms, which may likely become fatal

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Acute Obstructive Uropathy?

The complications of Acute Obstructive Uropathy include:

• Renal failure (which could be a permanent problem)
• High blood pressure (hypertension)
• Urinary tract infections

How is Acute Obstructive Uropathy Treated?

The main goal for treatment is to promptly relieve the obstruction and ease the symptoms. The treatment options of Acute Obstructive Uropathy may include:

• Bladder catheterization procedure (either through the urethra or abdomen) can be performed for immediate relief in case of BPH, bladder neck obstruction, or urethral stricture
• Definitive procedures to treat the underlying cause can be done at a later date. These may include:
  • Trans urethral resection of prostate (TURP), which is the removal of prostate through the urethra
  • Appropriate treatment of the cancers responsible for causing the obstruction 

How can Acute Obstructive Uropathy be Prevented?

Most cases of Acute Obstructive Uropathy cannot be prevented, since this normally occurs due to some underlying acquired health conditions. However, in some situations it can be prevented to a certain extent.

• Proper treatment of the underlying conditions, before it gives rise to complications
• In an individual with benign prostatic hyperplasia , certain medications can improve the flow of urine through an enlarged prostate and prevent Acute Obstructive Uropathy
• Elective treatment of individuals presenting with advanced BPH symptoms

What is the Prognosis of Acute Obstructive Uropathy? (Outcomes/Resolutions)

• If Acute Obstructive Uropathy is relieved or treated immediately, the kidneys resume their function uneventfully
• If the obstruction is left untreated for a long time, there may be permanent damage to the kidneys
• Treatment of underlying cause is needed to prevent recurrence of the condition

Additional and Relevant Useful Information Acute Obstructive Uropathy:

Acute Obstructive Uropathy can be unilateral (only one kidney is affected, as only one ureter is blocked) or bilateral (when both kidneys are affected due to poor drainage by the ureters). The bilateral condition is rare.