urinalysis Flashcards
what is filtrate? Why is the amount of urine produced each day so much smaller than the amount of filtrate?
Filtrate is the water and dissolved substances filtered out of the plasma by the glomerulus.
Why is the amount of urine produced each day so much smaller than the amount of filtrate?
The amount of filtrate is higher than the amount of urine excreted because substances that the body can still use are reabsorbed by the body. Such as sugar, 85-90% of the water and amino acids
What are the main waste products found in urine?
urea and creatinine;
What two substances are not found in the urine of healthy pets?
protein and glucose
What would happen to the cells of the body if the kidney didn’t balance the amount of salt and water through excretion or conservation of these elements?
Too much retained salt or too little plasma causes the cells to dehydrate and shrink; too little salt or too much water leads to cells absorbing extra water swelling and perhaps bursting
How does kidney function relate to blood pressure?
When blood pressure drops for any reason re-absorption of water by the kidney is increased causing concentrated urine
How does the kidney maintain the normal pH in the body?
The kidney selectively excretes acids and prevents the loss of bases
uremia
when kidney function is impaired and nitrogen-containing wastes (urea, uric acid, creatinine) accumulate in the blood
erythropoetin?
causes the bone marrow to make RBCs
How is kidney function related to anemia?
since erythropoietin is produced by the kidneys if the kidney function is impaired RBC formation will be reduced causing anemia
What is the difference between the ureter and the urethra (what do they connect to anatomically)?
The ureter carries urine from the kidney to the bladder; the urethra carries urine from the bladder to outside the body
What types of containers are appropriate for collecting urine samples for analysis?
Clean containers with no soap residue
If urinalysis cannot be performed within 30 minutes, how should urine be stored for exam later that day?
In the refrigerator in a sealed opaque container
If you stored the urine properly, what do you need to remember before you do the testing later that day?
Let the urine come to room temperature before testing
5 things that should be included when labeling a container of urine
patient/client name
date and time of collection
method of urine collection
contents (“urine”)
If any preservative was added to the sample, the name of the preservative should be included
When collecting a sample during normal voiding, should you place the container under the animal before it starts to urinate?
The first urine which is voided should not be collected to minimize contamination with cells or debris from the distal portion of the urethra. Wait until the stream starts them start collecting
What are two advantages and two disadvantages of collecting urine by “free catch”?
Advantages:
- sample may be collected by clients
- there is no risk of infection or trauma to the patient
Disadvantages:
- sample may be contaminated
- the animal may not urinate when the sample is needed
Describe how manual expression of the bladder is done
Moderate pressure is exerted on the bladder, Steady pressure should be applied, Pressure should be maintained until the urethral sphincters relax and urine is expelled
advantages and disadvantages of manual expression
Advantages:
- there is minimal risk involved in introducing bacteria into the urinary tract
- Urine samples may be collected at the convenience of the clinician Disadvantages:
- the bladder may be traumatized or rupture due to excess pressure
- The bladder may not contain an adequate amount of urine to perform this procedure
- Urination is difficult to induce in most conscious patients
- Urine may be forced back into the ureters and kidneys if excess pressure is used
What are two advantages and 2 disadvantages of the catheterization method?
Advantages:
- samples can be obtained directly from the bladder for culture with little risk of contamination if aseptic technique is followed
- The samples can be obtained at the convenience of the veterinarian
- The catheter can be attached to a collection bag in order to accurately monitor the quantity of urine produced
Disadvantages:
- trauma to the urethra may result in complications for the patient as well as creating a false hematuria
- Bacteria can be introduced into the bladder and urethra through the use of poor technique
cystocentesis
A small gauge needle (23 g, 1 1⁄2”) is attached to a new syringe. Careful placement of the needle in the bladder is important. Tranquilization/anesthesia is usually not required for this procedure
What is a disadvantage that may complicate interpretation of the urinalysis with cystocentesis?
There may be blood in the sample from the procedure if a blood vessel is penetrated by the needle.
Which method of collection is preferred if a culture and sensitivity test will be done?
cystocentesis
Why is collecting urine the first thing in the morning best?
sample is more concentarted
Can urine be frozen for later analysis?
no
Name 2 chemicals used to preserve urine
formalin, thymol, mucolexx
What do you have to do before adding preservative?
chemical and physical test
In a clinic, what is the only time you need to use a chemical preservative?
If urine cannot be tested within 4 hours-sending out to a lab
Name 3 things/categories that are always assessed on the physical exam of urine and 1 that is occasionally done
always: Specific Gravity, Color, Turbidity
occasionally: monitoring urine output for volume
What is specific gravity of urine a measure of?
Urine specific gravity is a measurement of the density of urine compared to pure water
What is the SG of distilled water?
1.000
What 2 instruments may be used to determine SG?
Urinometer and refractometer
What 4 factors will affect the SG of urine in a healthy animal?
Activity, Fluid intake, Diet, Climate
Concentrated urine will have which—a high SG or a low SG? What about dilute urine?
higher; lower
What is the SG when the urine is isosthenuric?
1.008-1.012
What is the significance of isosthenuria?
Kidneys are neither concentrating nor diluting the urine. This may not indicate renal disease unless it persists in the face of dehydration or over-hydration. Persistant isothenuria is present in complete kidney failure.
If a pet has a urine SG of 1.010 today, does that mean for sure that the kidney is not functioning?
No, All specific gravity values should be evaluated with other clinical and physical symptoms
A dipstick test shows a trace of protein. Is there a greater cause for concern if the SG was low or if it was high?
if it was low
How many decimal places should be used when recording SG?
3
Besides species, what are 5 other things that influence the volume of urine an animal produces?
body weight
diet
fluid intake
physical activity
temperature and humidit
List 3 methods of monitoring daily urine production in animals
Metabolism cage
indwelling urinary catheter connected to a collection bag
weighing bedding dry and then after urination
If an animal has polyuria, would the SG be high or low?
High urine volumes are associated with dilute (low SG) urine which is very light yellow to clear in color
Name 7 terms used in recording the color of urine and what each indicates
colorless= low SG, very dilute. May be normal if fluid intake is excessive or abnormal if the kidney is unstable to concentrate urine due to disease.
light yellow= low SG, dilute. normal high fluid intake
medium yellow= normal
amber= High SG high concentration a dark yellow that is almost orange normal. normal. fluid intake has been low
What are the 3 terms used in recording the turbidity of urine? Which 2 can be used together?
clear, cloudy, flocculent; cloudy and flocculent
What can cause urine to be cloudy?
milky or hazy due to large amounts of microscopic crystals or cells
difference between cloudy and flocculent
flocculence is floating flecks of material visible when urine is mixed. flecks are larger than the particles that cause cloudiness and can be seen individually with the naked eye
What can cause variation in the pH of urine?
urine from animals suffering from bacterial cystitis or contaminated urine that is allowed to stand the room temperature that may become more alkaline because of bacterial action
Name 4 factors that will lead to acid urine
normal in carnivorous animals
nursing calves and foals
diet with an excess of protein
starvation
fever
metabolic acidosis
prolonged muscular activity
Name 4 factors that will lead to alkaline urine
normal in herbivorous animals
vegetiable diets
bacterial decomposition of urine
urine retention; decomposition of urea, alkalosis, at room temperature urea decomposes to form ammonia which is alkaline
What change in pH happens if urine is not preserved properly? What causes this?
urine that is allowed to stand at room temperature may become more alkaline because of bacterial action
Dog, horse, Cat, Bull, Sheep, Pig, Elephant, Seal
acid 6-7
alkaline 8
acid 6-7
alkaline 7.4-8.4
alkaline
alkaline or acidic
alkaline
acidic
Which protein do dipsticks test for? Is a normal result positive or negative?
albumin; negative
Glucose in the urine indicates what condition maybe affecting the animal?
hyoerglycemia and possible diabetets
ketones are a result of
oliguria
Decreased urine output
polyuria
excessive production of urine
anuria
absence of urine
how to get urine from large animals
cattle: rub straw near vulva
- sheep: occlude nostrils
- horses: warm cloth rubbed on abdomenm
normal specific gravity for cattle
1.015
