1. Lab Procedures Chapter 46:Urinalysis
Professor Fowler

2. introduction
Urinalysis: the testing of urine for the presence of infection or disease
One of the most commonly performed tests
Readily available, easily collected, and often provides the first clues to illness
Void: urinate
Micturate: urinate

3. asepsis
Very important in urinalysis!!!!

4. Collecting the specimen
Urine samples provide valuable indicators of the overall health of the pt
Generally at least 10mL is needed for testing

5. Collecting the specimen
Routine (random) sample
Most commonly collected type
Collected in non-sterile container
Used for routine screenings
Morning specimen: first void
Most concentrated
Used for pregnancy tests, urine cultures, and microscopic exams
Should be brought to office within 30 minutes to 1 hour

6. Collecting the specimen
Timed specimen
Necessary for quantitative analysis of substances (protein, creatinine, glucose)
24 hour specimen
Used to determine the glomerular filtration rate of kidneys, check hormone levels, and to check for other metabolic abnormalities
Procedure 46-1
2-hour postprandial: two hours after a meal
Used as a screen for glucose that may be spilled into urine once blood levels exceed renal threshold (concentration at which a substance excreted by kidneys begins to appear in urine)

7. Collecting the specimen
Catheterization specimen: used to collect a sterile urine specimen – catheter inserted into urethra into bladder to obtain sample – figures 46-3A, B and figures 46-4 A, B
Clean-catch midstream specimen – Procedure 46-2
Pediatric specimen: attach a pediatric urine specimen bag
Suprapubic specimen: puncture performed using a sterile needle and syringe so the resulting urine specimen is sterile

8. Routine urinalysis Physical Characteristics – normal values table 46-2
Begins with an exam of appearance, color, odor, quantity and specific gravity
Procedure 46-3
Appearance
Clear: can see through it – nothing seen floating
Cloudy: can not see through it – many things seen floating
Terms
Slightly cloudy, cloudy with sediment or turbid (cloudiness)
Turbid caused by bacterial infection, white blood cells, red blood cells, or epithelial cells
Always look before it cools as crystals form as it cools
Color
Normal color is straw (pale yellow)
Medications, vitamins, some foods can change color
Brown or black indicates serious condition
Reddish-brown may indicate bleeding
Orange may be result of Pyridium (used for bladder spasms)
Bright yellow may be from large quantities of B vitamins

9. Routine urinalysis Physical Characteristics Odor Quantity
Normally no odor
Fruity: possible ketones in urine
Putrid or foul odors might indicate infections
Ammonia odors usually result from breaking down over time
Quantity
Usually only measured with 24 hour urine samples
Polyuria: excessive amounts of urine production – DM or kidney disease
Oliguria: decreased amounts of urine production – dehydration, bleeding, decreased fluid intake or kidney disease
Anuria: no urine production – renal failure or obstruction
Specific Gravity: weight of a substance in relation to the weight of the same amount of distilled water – concentration changes throughout the day with fluid intake
Rough estimate of amount of substances dissolved in urine
Indicates how well kidneys can concentrate or dilute urine
Dipstick or reagent strip method
Refractometer method - Procedure 46-4 video

10. Routine urinalysis Chemical Characteristics – Procedure 46-5
Most common method is dipstick method
Chemicals on the strip react with specific chemicals in the urine to allow for measurement (color changes)
Dipstick tests are available for pH, protein, glucose, ketones, blood, bilirubin, urogilinogen, nitrite, leukocytes, and specific gravity
Tests provide info about the functioning of the kidneys, liver and other organs
Figure 46-11
Each test has a specific time before reading the results
DO NOT TOUCH TO OUTSIDE OF THE BOTTLE WHILE READING RESULTS!

11. Routine analysis Chemical Characteristics
pH: indicates acidity and alkalinity
Protein: normally not found in urine but may be found in urine after exposure to cold, strenuous exercise, or after eating large amounts of protein
Proteinuria (presence of protein in urine): can indicate renal dysfunction, preeclampsia, CHF, and glomerulonephritis
Glucose: normal urine has no glucose (sugar)
Glycosuria (sugar in the urine): may indicate DM, gestational diabetes, stress, infection, or Cushing’s syndrome, or medications
Sugar spills into the urine at about mg/dL
Blood: normal urine has no blood
Hematuria (blood in the urine): may indicate anemia, UTI, kidney stones or trauma unless it is from menses

12. Routine analysis Chemical Characteristics
Ketones: by products of fat metabolism
Acidosis may occur if prolonged fat burning for source of energy instead of glucose
Elevated ketones are common in conditions like poorly controlled DM, dehydration, starvation, ingestion of large quantities of aspirin and occasionally after general anesthesia
Bilirubin: product of breakdown of hemoglobin
Presence of bilirubin may be one of the first signs of liver disease, obstructive biliary disease, or mononucleosis
Large amounts will turn urine to yellow-brown to dark orange
Stored in dark as light breaks down bilirubin
Urobilinogen: result of RBCs destruction
Elevated in any condition causing an increase in bilirubin
Nitrates: by-product of chemical breakdown by certain bacteria
measurement is a method for detection of bacteria
If present, usually UTI
Leukocytes: white blood cells
When present, usually indicative of UTI

13. Routine analysis Reagent Tablet Testing
Some institutions routinely perform tablet testing when a reagent strip test for glucose is positive
Chemically created tablets are added to urine specimen and the resulting color is compared to a reaction chart to determine the presence of certain sugars
Procedure 46-6
Automated Urine Chemical Analyzers
Widely used in many types of facilities
Use light photometry to test the strips, which eliminates human error
Figure 46-17
Microscopic Examination
Identifies the type and approximate numbers of organisms present in a urine specimen
Helps physicians determine a disease process
MAs must be able to properly prepare a urine specimen for microscopic exam and understand the meaning and importance of the results of the microscopic exam
Procedure 46-7 (video)
Procedure 45-6 (video and demo?)

14. others Urine Pregnancy Test – Procedure 46-8
Two types of pregnancy testing: urine and blood
Both tests are based on the detection of hCG which is produced by the placenta and is present is the urine and blood of pregnant woman
First morning sample is preferred for urine testing because the concentration of the hormone is greatest at that time
Urine tests can be preformed at home and/or the office
Quality Control
System of ensuring that patients test results are accurate and reported in a timely manner
Should be done on regular basis, following protocol, and documented in quality control log
New employees should be trained to perform urine tests and the training documented
All instruments associated with urine testing should be cleaned and maintained on a regular basis and documented accordingly