What is urinalysis?
Urinalysis is a veterinary diagnostic test in which urine is collected and examined to gain insight into your pet's health and developing conditions. It can be used as part of regular preventive care and to diagnose the cause of specific symptoms.
Why would your veterinarian recommend a urinalysis?
There are several reasons why a veterinarian might suggest a urinalysis for dogs or cats:
- A urinalysis can help identify kidney disease, urinary tract infections (UTIs), and bladder stones. These conditions can be severe if left untreated, so early detection is crucial.
- Pets with diabetes, Cushing's disease, or other chronic illnesses may require regular urinalysis to monitor their condition and adjust treatment plans as necessary.
- Routine urinalysis can provide a comprehensive look at your pet's health. Even they are not showing any symptoms, this can help catch potential issues early.
- If your pet exhibits symptoms like frequent urination, blood in the urine, or difficulty urinating, a urinalysis can help pinpoint the cause.
What is the method for collecting a pet's urine?
The three ways that your pet's urine may be collected are:
Cystocentesis: This process uses a sterile needle and syringe to puncture the abdominal wall and collect the urine directly from the bladder. This method allows the urine to be collected without contamination from debris within the lower urinary passage. Cystocentesis is commonly used to detect bacterial infections and other kidney and bladder issues. Unfortunately, this method can only be used when your pet has a full bladder and cooperates.
Catheterization: This method of urine collection uses a catheter passed through the urethra and up into the bladder to extract urine. This option may be easier than cystocentesis as it is less invasive and easier to use. The downside is the possible irritation in the urethra and the chance of bacteria moving from the urethra and into the bladder during the process.
Mid-stream free flow: The easiest method of collecting urine is collecting it as your dog or cat relieves itself. It is called mid-stream free flow because it is recommended that the urine be collected halfway through voiding. You can even collect the urine on your own time. However, be careful that the sample does not become contaminated during collection.
What happens during the urinalysis?
When your vet performs a urinalysis, there will be four main parts to the assessment. They are:
- The evaluation of the urine for cloudiness.
- Measuring the concentration of the urine.
- Gauging the acidity or PH of the urine.
- Microscopic examination of the cells and solid material present in the urine.
Most commonly, the vet will look at the urine as a whole for the diagnostic evaluation. However, if your vet decides to complete a microscopic examination of the cells and solid material, they will need the urine sample to be concentrated or sedimented.
To create a concentrated urine sample, your vet will place the sample of your pet's urine in a tube and run it through the centrifuge at very high speeds. This will cause the heavier materials to move to the bottom of the sample for analysis using a microscope.
How is a urinalysis performed?
A chemical analysis is completed using a dipstick. A dipstick is a small strip of plastic that holds a series of individual test pads. The pads are designed to change color depending on the concentration of different elements in the urine.
The dipstick is dipped into the urine, and after a short waiting period, the color of the test pads is compared to a chart that translates the intensity of the color to an actual measurement.
What will a urinalysis show your vet?
A urinalysis can measure the following:
- Protein: The presence of protein in urine is called proteinuria. While trace amounts of proteinuria in concentrated urine may not cause your vet to worry, proteinuria in dilute urine should be considered dangerous since it may indicate kidney disease. The significance of proteinuria is often determined by doing a second test called the protein creatinine ratio test.
- Glucose: Your vet should not find glucose in your pet's urine. The presence of large amounts of glucose usually indicates your pet has diabetes. Small amounts of glucose in the urine may also be found in pets with kidney disease.
- Ketones: When your pet's body breaks down stored fats as an energy source, ketones can result. This occurs most frequently in diabetes but can also be found in healthy pets during prolonged fasting or starvation.
- Blood: If blood is found in the sample, your pet is experiencing bleeding somewhere within their urinary system. Sometimes, this is due to how the sample was collected. For example, small amounts of blood are often found in samples collected by cystocentesis or catheterization. Blood in the urine is associated with bacterial infection, bladder stones, trauma, or cancer. So, further investigation is recommended if the blood in the urine does not appear due to the sampling method.
- Hemoglobin: If your pet has hemolytic anemia, blood can be found in the urine. Hemolytic anemia occurs when red blood cells are destroyed, and a protein called hemoglobin is released. Hemoglobin passes into the urine and causes the blood test pad to show positive, even though there is no bleeding in the urinary system.
- Myoglobin: If your pet experiences trauma, such as a torn muscle or ligament, blood may also be present. This is because damaged muscle fibers release a protein called myoglobin, similar to hemoglobin. Myoglobin will also cause the blood test pad to show positive, even though there is no bleeding in the urinary system. A specific test for myoglobin can be done if muscle injury is suspected.
- Urobilinogen: Urobilinogen in urine indicates that the bile duct is open and that bile can flow from the gallbladder into the intestine.
- Bilirubin: Bilirubin is a substance produced in the liver and normally excreted in the bile. Bilirubin is not found in the urine of healthy cats but may be found in small quantities in the urine of healthy dogs. Abnormal amounts of bilirubin in the urine are associated with liver disease or red blood cell destruction (hemolysis), and should always be investigated.
Understanding Dilute Urine in Dogs
One specific finding that may come up in a dog urinalysis is dilute urine. This means the urine is less concentrated. Dilute urine in dogs can be a sign of:
- Your dog drinking more water than usual, which can dilute the urine.
- The kidneys not concentrating urine properly, a common issue in dogs with kidney disease.
- Conditions like diabetes insipidus or Cushing's disease.
If your dog's urinalysis shows dilute urine, your veterinarian will likely recommend further testing to determine the underlying cause.
Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.