Urine Analysis and What It Means
There is a tendency to consider a dipstick analysis as a complete urine analysis. Unfortunately in doing so, very important parts of a urine analysis are missed out on, namely specific gravity and sediment examination.
While a dipstick test is available for specific gravity, accuracy is not always as good as required, and sediment examination provides essential information on red blood cells, white blood cells, bacteria, casts, crystals and other cells in the urine.
There again, while specific gravity provides a good indication of the ability of the greyhound to retain water. Any specific gravity test, if looked at in isolation without considering the hydration of the dog, forced fluid intake such as extra water added to the meal, the addition of alkalizing diuretics to the diet, or the effects of a recent run, may provide a misleading result.
Correct sample collection is also of extreme importance, a clean container must be used as any contamination, and even soap or detergent will alter test results.
It is also best, if first urine of the morning can be collected, and a midstream sample if possible, to reduce the chance of bacterial contamination.
Wiping the animal first with a clean tissue will also help in this regard.
It can not be stressed enough that the sample should be tested when the urine is fresh, any sample left longer than 20 minutes should be refrigerated and tested within a few hours.
If these are normal, an Anti Diuretic Hormone response test should be carried out.
Therefore, no specific urine Ph is abnormal, except as it relates to other findings from urine analysis, and to the acid-base and electrolyte balance as a whole.
Urine Ph 7.1 and
However, if the urine is markedly acidic (6.0 or lower) a systemic problem may exist and further investigations should be undertaken.
Urine Ph 7.0 and
Some of the types of bacteria that cause urinary tract and kidney infections produce an enzyme that breaks down to ammonia and turns the urine alkaline.
Consistent alkaline urine in dogs may also cause the formation of a type of kidney stone (crystals); these may also be caused by the indiscriminate use of sulphonamide antibiotics.
Another reason for persistent alkaline urine may be the inability of the kidneys to re-absorb bicarbonate.
Any consistently alkaline urine should be investigated, including a urinary sediment examination.
Protein urine dipstick tests are qualitative and are recorded as a trace to 4+.
To accurately interpret the significance of protein in the urine, the urine specific gravity must be known. Simply because a small amount of protein may read as negative in urine with a specific gravity of 1.010 but positive in urine concentrated to 1.045.
A small amount of protein in the urine is normal, provided that the specific gravity is in the normal range for the state of the dog being tested, however any amount of protein in the urine at a specific gravity of less than 1.030 may be abnormal.
Blood in the urine can provide a false positive reading for protein in the urine, because proteins are present in blood in large quantities, compared with the amount of protein in normal urine.
There are a number of diseases that cause increased quantities of protein in the urine including kidney disease; therefore any significant increase in protein in the urine should be investigated.
Causes of a positive reading may include impaired liver function, persistent fever, and chronic diseases involving blood glucose levels.
The most common cause of glucose in the urine is an elevated blood sugar to a level that exceeds the ability of the body to re-absorb the glucose, however this is extremely rare if not unheard of in greyhounds.
However, dark urine does not necessarily indicate that the kidneys are concentrating the urine in a fluid saving effort.
Hemoglobinemia acid urine colours the urine a smoky brown while in alkaline urine the colour is red.
If a urine sample is to be checked for Red Blood Cells it should be done as soon as possible after the sample has been collected, as RBC’s start to breakdown within minutes, releasing HAEMOGLOBIN into the urine. (HEMOGLOBINURIA)
The presence of blood in the urine may indicate a variety of diseases ranging from kidney- nephritis, cysts or trauma to infections in the bladder, urethra, prostate, or genital area. While HAEMOGLOBIN only in the urine may indicate a blood disease, bacterial infection, red blood cell parasites, or even some type of chemical poisoning.
Brown Red Urine
Myoglobin is released from the muscle tissue following excessive exertion (RHABDOMYOLYSIS) or trauma such as torn muscle fibres.
The presence of Myoglobin in the urine indicates the need for a thorough muscle check, and a blood test for muscle enzymes to rule out muscle disease.
Myoglobin in the urine may also adversely affect the kidneys (toxicity) and the greyhound should receive intense fluid therapy.
Blood, Haemoglobin and Myoglobin will all give a positive result to occult blood with a dipstick test.
Taken from: Greyhound Urine Analysis