You want to run what tests on my cat? Why? What is it going to cost me?
Periodically, either as a health screening, or because we are looking for a specific disease process, we will want to do various tests on your cat. These include but are not limited to; blood work, urinalysis, x-rays, ultrasound, and blood pressure measurement.
Blood work. These are pretty common tests that we run. There are many different types of blood work that we will run on cats. The most common four are FeLV/FIV testing, CBC, serum chemistry, and a total thyroid level.
FeLV/FIV - Feline Leukemia and Feline Immunodeficiency Virus. This is a common test done in kittens and cats that come into your home from unknown backgrounds. Because these are life-threatening viruses that are potentially contagious to your existing cats, or that could just shorten your new cat's life span, we recommend testing all new cats to the home that are unknown as to their virus status. This test only requires a few drops of blood, and we have results in 10 minutes.
CBC - Complete Blood Count. This blood test measures your cat's red and white blood cells, and tells us how many of each of them there are, and if they are normal in size or not. This can indicate many different disease processes, not the least of which is systemic infection. We need about 0.5cc of blood for this test, and it is sent out to an outside lab.
Serum chemistry. This test measures your cat's liver enzymes, kidney enzymes, glucose, electrolytes, and blood proteins. This test can give us a lot of information regarding many metabolic diseases. We can either run this test in house, which requires about 0.2cc of blood, or send it out to an outside lab, which requires about 1cc of blood.
Total thyroid level. This test is a screening test to check for the presence of hyperthyroidism. While cats almost never get hypothyroidism, a low thyroid can also indicate what we call sick euthyroidism, which can indicate a significant disease process going on in your cat. We can also either run this test in house, which requires about 0.2cc of blood, or we can send it out to an outside lab which requires about 1cc of blood.
Urinalysis. One of the most common reasons we see cats is for urinating outside of the litter box. In about 80% of cases, this is caused by painful urination such as a bladder infection, urinary crystals, or interstitial cystitis. The other 20% are usually caused by a behavioral reason. However, we cannot tell what the cause is without checking the urine first. Even when it seems like it might be behavioral in nature; a lot of those are actually painful urination, sometimes triggered by stress.
There are 4 ways we can obtain the urine to be examined. You can collect it at home. There are a few ways to do this. One is to put a non-absorbable litter in a clean washed out litter box. Non-absorbable litter would include aquarium gravel, unpopped popcorn kernels (although if they are dusty you may need to rinse and dry them first), or we also have two commercial products at the clinic called No-Sorb and Hydrophobic Sand. Once your cat urinates in the box, you can just drain it into a clean container of some kind and bring it in to us. You can also try putting a garbage bag down in an area that you think your cat will urinate on, and collect it off the top of the garbage bag. It is best if you can bring it in within 12 hours of when your cat urinates, and if it will be more than an hour, put it in the fridge until you can bring it in. We need at least a ½ teaspoons worth, but the more, the better.
Another way is to bring your cat to the clinic and let them stay with us until they urinate. They have a litter box with non-absorbable litter, food, water, and a comfortable grate underneath them. Once they urinate, we can collect it. Most cats though will hold it for 24-36 hours before they go. The last two ways to collect urine are not very pleasant for the cats, but we can obtain a sample quickly, and they can go right back home. Assuming that they have enough urine in the bladder, we can express their bladder, which involves putting pressure on both sides of the bladder until they cannot hold it anymore, and urinate. We can also do what is called a cystocentesis which involves using a syringe to draw the urine out of the bladder by inserting the needle directly into the bladder. Both methods are generally safe, but not the most comfortable way for your cat to go.
Once we have the urine, we will first put a few drops on a dipstick, which will indicate some of the chemical properties of the urine, such as if there is glucose in the urine, protein in the urine, bilirubin in the urine, and to what extent. We will then check the specific gravity on a refractometer, which measures the concentration of the urine. This can give us information regarding the kidney function among other things. Last, we will spin the urine down in a centrifuge, and look at the cells in the urine under the microscope. This can tell us if there are elevated white blood cells, red blood cells, crystals, or any other abnormal cells in the urine. Based on this information, we can tell if the urine is normal or abnormal, and if abnormal, a likely reason for it, such as a urinary tract infection.
X-rays. This is basically a snapshot of your cat's insides. While we can't see everything, we can get a lot of information from what we can see.
Bones - we can see if there are any broken or fractured bones, and if there are any bone abnormalities such as infection or cancer. We can also see if there is significant arthritis, or joint abnormalities.
Heart - we can get a pretty good idea of the size of the heart, if it is enlarged or has increased definition, both of which can indicate heart disease. We can also see if any of the large blood vessels in the chest are abnormal - either enlarged, which could indicate high blood pressure or heartworm, or smaller than normal, which can indicate dehydration.
Lungs - we can see if there is any fluid, either inside the lungs or outside the lungs, which can indicate several different disease processes. We can see if there is evidence of chronic inflammation, such as with asthma, or if there are nodules, such as with fungal pneumonia or cancer metastasis.
Liver - if the liver is enlarged, or has rounded edges, this can indicate an ongoing liver disease. If the liver is smaller than normal, this could indicate cirrhosis or a portosystemic shunt, which is when a significant blood vessel bypasses the liver instead of going through it.
Stomach - if the stomach is full of something, and your cat hasn't eaten for 12 hours or more, this can indicate a foreign body such as a large hairball. If your cat ate something that contained metal or hard plastic, we can see that in the stomach too. Unfortunately, small objects that are not made of metal or thick hard plastic will not show up on an x-ray in the stomach.
Intestines - if the intestines have abnormal gas patterns, this could potentially indicate a full obstruction by a foreign body. If the intestines look abnormally thickened, it could indicate a chronic inflammatory condition, such as inflammatory bowel disease, food allergies, chronic intestinal parasites, or even cancer. For obese cats that we cannot adequately palpate, we can also check for signs of constipation.
Kidneys - we can see the shape and size of the kidneys to assess if there is possible kidney disease present, and if there are any stones present in the kidneys. Smaller kidneys can indicate a chronic kidney disease, larger than normal kidneys can indicate an acute kidney disease that may still be treatable. Misshapen kidneys can be an indication of chronic kidney disease, or cancer.
Spleen - normally the spleen is just a little thing on the x-ray. If the spleen is enlarged, this could indicate a blood infection such as feline infectious anemia, an auto-immune disorder, or cancer.
Bladder - a normal bladder looks like a teardrop laying on its side. If it is abnormally distended, if there are stones present, or even sometimes if the bladder is misshapen, it can indicate a significant disease process.
Ultrasound. This is a way to see inside of the moving body organs using sound waves. While the x-ray gives us an overall view of the outside, the ultrasound gives us a smaller view of the inside. For example, we can see inside of a heart to see if the heart walls are thickened or stretched out, and if the heart is pumping normally. We can see inside of the liver to see if the tissue is reflecting consistently or abnormally, which can indicate several different types of liver disease. We can see inside of the kidneys to see if the architecture of the kidney is normal or abnormal. We can see if the intestines are moving normally in what is called peristalsis as they digest food, and if they are abnormally thickened in the walls. We can see if the inside lining of the bladder is smooth, thickened, or lumpy. We can see if the spleen has abnormal areas of reflection in it. If we are good enough, we can also see if the pancreas is thickened, as with pancreatitis, and if the mesenteric lymph nodes are enlarged. If there is a tumor somewhere in the abdominal or chest cavity, we may be able to see that too.
Blood pressure. Just like people get high blood pressure, so do cats. High blood pressure, or hypertension can be a primary disease, or secondary to other diseases such as kidney disease, hyperthyroidism, or diabetes. Hypertension is very hard on the body organs, especially on the heart, the small vessels in the back of the eye, and on the kidneys which have a very fine blood filtering system inside of them. If your cat is diagnosed with one of the diseases that can cause hypertension, if we hear a heart murmur, or if we just want to rule it out, we will check your cat's blood pressure.
This is a very simple process. We have a cuff that we will place on your cat's tail, or if they don't have a tail, we will check it on one of their legs. This is very similar to how you get your blood pressure checked. We will inflate the cuff, and it will take readings as it deflates. Unlike you though, cats tend to get a little more stressed at the vet than you may get at your physician, so we will often take up to 30 readings to try and get the most accurate numbers, and then average them out. A normal cat BP at home at rest is about the same as you, 120/70. We allow about 50 points on the top number, the systolic number, for stress. So, if the top number is under 170, that is normal. Anything from 170-190, we look to see if the cat is excessively stressed. If yes, then we consider it normal. If no, or if the top number is higher than 190, than we consider that hypertension and will start your cat on medications to lower their blood pressure. If we don't already know a possible cause, we may also then want to do blood work to look for a reason for the hypertension.
There are a multitude of other tests that we may want to do on your cat to fully diagnose them so we can give them the best treatment possible to improve their quality and longevity of life. These are just the most common tests that we run.