What’s the topic for today?
Today’s interesting topic is all about URINE!
Great! I’ve always wanted to know lots about urine. Why do vets get so excited about these things?
You can tell quite a lot about an animal’s health simply by checking out its urine. A urinalysis is a quick screening test that can rule out lots of problems.
So what are you looking for in a good urine sample?
Well, before we even look at the urine, we ask the owner lots of questions about their pet’s urination habits, as that can give us valuable information. We need to know how frequently the pet urinates, how big the volume is and if there is any straining. Basically, we want to know if anything has changed about their pet’s urination habits.
What sort of problems are you looking for?
An increase in the volume of urination can indicate kidney disease or hormonal problems like diabetes, whereas an increased frequency can be due to a urinary infection.
What do you look for in the urine itself?
Firstly, we look at the colour and whether it is cloudy. A good sample will be a clear yellow colour. Any cloudiness could indicate infection. We then smell it!
Urine should have a good nose then?
A good quality fresh dog urine should be pretty odourless, and a strong ammonia smell suggests infection. It’s normal for a cat’s urine to smell of…well, cat’s urine.
What sort of tests can you do on urine?
Lots. The first test is to measure its concentration. Very dilute urine indicates possible kidney or hormonal problems, whereas very concentrated urine tells us that the kidneys are working very well, but that the animal may be dehydrated.
What else can you tell from urine?
We measure the pH. Alkaline urine often indicates infection. Cat and dog urine are usually mildly acidic. Bladder stones can develop in the bladder if the pH is incorrect, and we sometimes have to use special diets to control the pH of the urine.
Bladder stones sound painful!
They can be very irritating, to say the least. We also check urine for glucose and ketones, as these can be elevated in diabetes. Normal urine should have no glucose or ketones in it.
What changes do you see in the urine in kidney disease?
It will be very dilute and look like water. The earliest indicator of kidney disease is actually the amount of protein in the urine. We look at the ratio of two proteins to see if there is any evidence of early kidney disease. Also, if we centrifuge the urine, we can look at the sediment under a microscope and in kidney disease, we sometimes see what we call urinary casts. These are due to clots that occur in the kidneys and end up in the urine.
Can you see other things in the urine using a microscope?
Yes, we can see bacteria to confirm if there is an infection, and if there is, we send the sample away for culture. If the bladder is inflamed, we will also see red and white blood cells in the urine, and if there is bladder cancer, we may see cancer cells. Also, we might see mineral crystals in the urine, especially if bladder stones are present.
I had no idea you could tell so much from a urine sample. Is there anything you haven’t mentioned yet?
Well, we can send the urine to a laboratory to analyse all sorts of things like hormones and a few toxins, for instance, and this can help make a diagnosis.