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Cats + Diagnosis

  • Ultrasound uses the reflection of sound waves to generate an image of internal structures allowing for identification of masses, pregnancy diagnosis, abnormal heart function and muscle size, abnormalities of the orbit, and abnormal appearance of abdominal organs. It cannot be used to identify abnormalities in areas of air such as the lungs, or areas surrounded by bone. Ultrasound-guided biopsies can be taken of abnormal areas which are sent to a pathologist for interpretation. Anesthesia is generally not needed unless tissue biopsies are planned. Shaving of fur is recommended to allow best contact of the probe with the skin to produce the most diagnostic images. Ultrasound results can be analyzed in real time; however, assessment by a radiologist may take several days. Ultrasound is an invaluable tool to detect problems in a non-invasive fashion.

  • Urinalysis is an important part of any comprehensive workup or health screen as it provides information on the urinary system including the kidneys and bladder and also can support diagnosis of metabolic disease such as diabetes mellitus. Urine collection methods include cystocentesis, catheterization, or mid-stream free flow, each of which has their own pros and cons. Urine samples are assessed using the following parameters: appearance (color and turbidity), concentration assesses how the urine has been concentrated by the kidneys, urine dipsticks (assess pH, glucose, protein, blood, ketones, urobilinogen, and bilirubin), and microscopic exam of sediment (may reveal the presence of abnormal cells including red blood cells, white blood cells, and tissue cells or crystals). A cytological preparation of sediment may be recommended to look at tissue cells in more detail.

  • Cortisol is a stress hormone that is excreted from the body in the urine. Creatinine is a product of muscle metabolism and it is normally lost in the urine at a relatively steady rate. The ratio of cortisol to creatinine in the urine can be used to account for the effect of urine concentration. Urine cortisol/creatinine ratio is usually evaluated in animals suspected of having Cushing's disease. This test involves the collection of a single urine sample, taken first thing in the morning. Ideally, this sample should be collected at your home, to minimize the effects of stress.

  • The presence of protein in urine is called proteinuria. This may indicate that the kidneys are not working properly. In some situations, it may even be a sign of kidney failure; however, bleeding or inflammation in the urinary system is a far more common cause of proteinuria. If proteinuria is not due to inflammation or bleeding in the urinary system, then it is more likely to be a sign of true kidney disease. Your veterinarian may recommend further testing if the urinalysis reveals inflammation or bleeding.

  • The urine protein:creatinine (UPC) ratio is a simple test that measures how much protein is being lost through the kidneys. Creatinine is a substance that appears in the blood as the result of muscle activity and is excreted by the kidney at a constant rate. The urine protein:creatinine ratio measures whether the excretion of protein is greater than expected when compared to the excretion of creatinine. Before the protein:creatinine ratio can be interpreted, two other measures of kidney function should be taken. These are blood urea nitrogen (BUN) and serum creatinine. In order to make a definitive diagnosis of kidney disease, repeat tests of protein:creatinine ratio and urinalysis on at least three consecutive urine samples taken at 2-week intervals is recommended.

  • Feline viral testing typically encompasses testing for feline leukemia virus (FeLV), feline immunodeficiency virus (FIV), and coronavirus which causes feline infectious peritonitis (FIP). FeLV is one of the most important highly contagious viruses in cats as it is responsible for a number of diseases including leukemia. FIV is a virus that weakens the immune system's response to other infectious agents. Testing for FeLV and FIV is recommended to detect underlying causes to illness, to screen apparently healthy cats who may have been exposed to the viruses, and to identify carriers of the viruses prior to introducing cats into a household of other cats. FIP testing is somewhat more problematic.

  • Testing for FeLV is recommended to detect underlying causes to illness, to screen apparently healthy cats who may have been exposed to the viruses, and to identify carriers of the viruses prior to introducing cats into a household of other cats. Testing for coronavirus is indicated when FIP is suspected. In-clinic blood tests are available for FeLV. Confirmatory testing of any positive tests is recommended at referral laboratories, usually using DNA tests. Vaccination against FeLV will not affect the outcome of a cat already infected with the virus nor will it affect testing.