Laboratory testing

Urine testing is an essential part of identifying the cause of urinary problems. Among other things, it helps us check whether an infection is present, whether the kidneys are functioning correctly, and whether crystals are present that could irritate the urinary tract.

Urine testing is also an essential complement to blood testing. Early kidney problems, for example, can often be detected in the urine before they show up in the blood. A urine sample also provides valuable information about urine concentration and can help identify conditions such as diabetes.

For these reasons, urine testing, alongside a clinical examination, is also a valuable tool for screening your pet's general health. This can be useful, for example, before an operation or as part of a health check in older animals.

For a reliable test, we often prefer a morning urine sample, as it gives the best picture of the kidneys' ability to concentrate urine.

How is a urine sample collected?

Collecting a urine sample seems simple, but isn't always straightforward. With dogs, it can sometimes be a challenge to catch a suitable sample, while with cats it often seems even more difficult.

Fortunately, there are special granules that can temporarily replace the litter without affecting the composition of the urine. This makes it possible to collect a usable urine sample from cats as well.

However, the preferred method is often to collect urine directly from the bladder using a fine needle. Although this sounds unpleasant to many owners, most animals experience little discomfort from it. Cats, for example, often respond surprisingly calmly to it. Of course, this does require enough urine to be present in the bladder.

The major advantage of this method is that the urine is collected in a pure, uncontaminated state, without possible contamination from the urethra or prostate. This makes the test results more reliable.

What do we test for?

At our practice, we can carry out a basic urine test. Among other things, we check:

• the density (specific gravity) of the urine;
• the urine sediment for, among other things, crystals;
• the presence of protein loss;

• the presence of sugar loss.

In some cases, additional testing is needed. In that case, we send the urine sample to an external laboratory for a urine culture. This allows us to confirm or rule out a bacterial bladder infection.

Faecal testing is mainly carried out to check for parasites in your pet's gastrointestinal tract. Because some parasites don't continuously shed eggs or other stages in the faeces, we usually prefer a pooled sample collected over several days. This increases the chance of correctly detecting an infection.

Besides detecting parasites, faecal testing can also provide valuable information about other digestive conditions. Certain bacteria and viruses can be detected in the faeces, and the test can also check for blood loss. This blood loss isn't always visible to the naked eye.

A faecal test can also give an indication of how well digestion is functioning and help identify the cause of digestive problems.

Faecal testing is therefore an important tool in diagnosing stomach and intestinal problems, and helps us start targeted treatment when needed.

A fine needle aspirate can often provide valuable information and has the advantage of being quick, simple and involving little discomfort for the animal. However, this technique also has limitations. Because only loose cells are collected, the structure of the tissue is lost. This means a definitive diagnosis isn't always possible.

In such cases, it may be advisable to remove a piece of tissue for further examination. This is called a biopsy. By examining not just the cells but also the tissue structure, we can often obtain more information about the nature of an abnormality.

Depending on the location of the biopsy and the animal's temperament, this can be done under local anaesthesia, a combination of sedation and local anaesthesia, or general anaesthesia. Biopsies of internal organs are usually taken under ultrasound guidance.

Different techniques exist for taking a biopsy. In many cases, we use a punch biopsy, in which a small circular instrument removes a piece of tissue. For certain internal organs, we use special biopsy instruments that take a cylindrical tissue sample. In exceptional situations, it may be necessary to surgically remove a larger piece of tissue.

Each technique has its own advantages and disadvantages. That's why we always carefully weigh the animal's comfort, the invasiveness of the procedure and the likelihood of a reliable diagnosis. This allows us to choose the method that provides the most information with the least burden on your pet.