Urine- "So Little Effort, So Much Information!"

In certain diseases, it is sometimes necessary to examine an animal's urine. Some people find this thought a little disconcerting, but the information yielded is definitely worth the trauma of having to collect the sample!

 

A clean collection will result in useful information. Did you know that rusty jam jar lids, left-over sweet sauces, floor cleaner contaminants,soil in the collection jar or crystals in the cat litter can lead to some pretty abnormal and interesting results?

Urine can be obtained by:

 

• "free-catch"- catching the stream into a clean, rinsed and dry glass or plastic container- most owners can do this

• "catherisation"- passing a fine tube into the bladder- a veterinary procedure

• "cystocentesis"-another veterinary procedure where a fine needle is passed into the bladder via the abdomen. This last method sounds very dramatic, but is usually very well tolerated by patients often with minimal restraint. This often gives the best, least contaminated result.

 

Urinalysis is composed of several different stages. The first step is to separate a portion of the urine into a test tube and spin it in a centrifuge. This allows later examination of the cells within the urine sediment.

 

While this sample is being centrifuged, another portion is placed onto a urinary biochemistry stick. The colours on each of the biochemistry squares change according to the concentration of various compounds in the urine. These concentrations are determined using a calibration chart. Information about the pH of the urine, presence and amount of protein, blood, glucose, ketones and other compounds is gathered from this test.

 

After the biochemical tests have been completed, a refractometer is used to determine the specific gravity of the urine. This allows us to tell if the kidneys are working to keep the urine concentrated or not, or whether any other disease might be causing the urine to be inappropriately dilute.

 

Once this has been completed, the urine that commenced spinning in the centrifuge is examined under a microscope. We examine this concentrated urine with and without stain. The unstained sample is used to determine if any crystals are present in the urine. There are a number of different types of crystals that animals can develop, in both acidic and alkaline urine. The stained sample of concentrated urine is used to determine whether cells, casts or bacteria are present. This information helps us build up a picture of exactly what is going on in your pet's urinary tract.