Urine and Urination

Introduction: Problems with the bladder and urinary tract can be very diverse and sometimes confusing. The confusion often results from the terminology commonly used to describe a particular problem. To help avoid some of the confusion, the following definitions are beneficial:

Common Terms:

  1. Incontinence - The inability to control urination. An animal that is incontinent may urinate during sleep, in the house, when excited, and at other improper times or places.
  2. Urinary obstruction - Blockage of the normal path for urine to exit the body.
  3. Bladder atony - Where the bladder does not have the proper muscle control to expel urine.
  4. Urine retention - Where urine is held within the bladder for abnormally long periods of time. This can be the result of nerve and/or muscle problems.
  5. Hematuria - Referring to the presence of blood in the urine.
  6. Myoglobinuria - Referring to the presence of muscle breakdown products in the urine. The urine is often discolored (brown or tea colored).
  7. Bilirubinuria - The presence of bilirubin, a product of red blood cell break-down, in the urine.
  8. Dysuria or Stranguria - Painful, abnormal, or difficult urination.
  9. Cystitis - Inflammation of the bladder. This condition can be caused by infectious disease, tumors, and irritation from an outside source.
  10. Nephritis - Inflammation of the kidneys. This condition can be caused by infectious diseases, abnormal injury of the kidneys by the body’s immune system, or irritation from an outside source.
  11. Polyuria - The abnormal production of too much urine.
  12. Oliguria/Anuria - Producing too little urine or no urine at all.

Causative Agents/Clinical Signs: The above conditions can be caused by many different problems within the body. Some of these are listed below:

  1. Urine incontinence, retention, and bladder atony can be caused by nerve and muscle damage or disease. This is common in some traumatic injuries to the back and pelvis.
  2. Urinary obstruction can occur because of stones in the kidneys, ureters, bladder, or urethra.  Tumors and scar tissue can also cause obstruction.
  3. Hematuria can be caused by kidney disease or damage, infection or tumors in the urinary tract, physical injury to the urinary tract, or bleeding disorders.
  4. Myoglobinuria is caused by muscle injury and trauma.
  5. Polyuria may result from a variety of abnormalities with the body’s metabolism of water. Diabetes, Cushing’s disease, Addison’s disease, liver disease, kidney disease, severe infections, and some types of cancer may cause polyuria.
  6. Oliguria and anuria are usually the result of severe kidney disease.
  7. Almost any problem associated with the urinary system can cause stranguria or dysuria.

*Many of the above conditions can also be caused by bladder infections.

Diagnosis: The diagnosis of these problems involves several major areas:

  1. Physical exam and history:
  1. This may include palpation (handling) of the abdomen and bladder, a rectal exam, and a neurologic exam.
  1. Additional tests:
  1. Urine analysis (U/A) - See page D895 for additional information. Urine specimens may be obtained by catching a sample during normal urination (easiest, but poorest method for diagnostic purposes, especially in cases of cystitis), insertion of a catheter into the bladder through the urethra, or by cystocentesis. Cystocentesis is the insertion of a sterile needle through the body wall directly into the urinary bladder for the retrieval of a urine specimen. Cystocentesis is the method most likely to yield the most helpful results. This is especially true when a bacterial culture must be performed.
  2. Complete blood count (CBC) - See page D120 for additional information.
  3. Blood (serum) chemistry analysis - See page D80 for additional information.
  4. X-rays (radiograph) of the abdomen, kidneys and pelvis regions. Sometimes contrast material (dye or air) is placed into the urinary tract to allow a better view of important structures. See page D702.
  5. Ultrasound of the kidneys, ureters, bladder, and urethra. See page D880 for additional information.
  6. Endoscopic exam of the bladder and lower urinary tract (cystoscopy, urethroscopy).

Treatment: The treatment can be as varied as the underlying problems which result in the various disorders. In general, the underlying cause for the urinary problem must be treated first. This treatment may include antibiotics, anti-inflammatory drugs, fluid therapy, insertion of a catheter into the bladder, hormone therapy, or surgery. Some nerve and muscle injuries require special medications, rest, and time before full function is achieved; however, in severe cases, full function may never return.