Urinalysis Flashcards
What are three reasons urines provide testing significance in clinical setting?
- diagnosis of disease
- monitoring the progress of disease
- monitor the effectiveness of therapy
What is a random urine specimen?
Urine sample taken at any time of the day, no fasting
What is a first morning urine specimen?
Urine sample taken when the patient wakes up, prior to any other voiding.
What is a timed urine specimen?
A urine specimen that is taken at a specific time of day.
What is a 24 hour urine specimen and what purpose does it serve?
Urine sample taken over the course of 24 hours. It measures the total volume of solutes excreted and shows diurnal variation.
If there is a delay in testing urine samples what should be done to maintain its integrity?
Refrigerate between 4-8C
If there is a delay in transportation of urine samples what should be done to maintain its integrity?
refrigerate for 24 hours prior to transportation, and place in a bacteriostatic preservative.
If there urine specimens are to be transported over long distances what should be done to maintain it’s integrity?
Refrigerate for 24 hours prior to transportation, and place in a bacteriostatic preservative.
- Dip an agar film which is sent with the urine container.
List three things that could deteriorate the integrity of reagent test strips?
- exposure to light
- exposure to room humidity
- touching the reagent test pads
During what time frame should urines be tested in?
Within 2 hours
What two elements in a urine cannot be tested for if the urine has been refrigerated?
- Bilirubin
- Urobilinogen
What can two elements can precipitate due to refrigeration of urines? What interference may they cause?
Amorphous urates and phosphates
- cause interference when microscopically examining urine.
At what speed and what time are urines centrifuged for?
5 minutes
See SOP, or owner manual for the RCF at which urines are to be spun at.
When performing QC why should your positive reagent produce weak positive reactions?
For early detection of disease and elevated results
What is the preferred urine sample? For what reason?
First morning sample
- Concentrated (incubation)
- higher amounts of formed elements = easily detectable
What four things determine if a urine requires microscopic evaluation?
- Protein
- RBC
- WBC
- Nitrites
What are you looking for on low power fields, in a urine microscopic analysis ?
- crystals
- enumeration of casts
- Elements in few fields
What are you looking for on high power fields, in urine microscopic analysis?
- # cells
- # bacteria
- # crystals
- # parasites
- classification of casts
How are RBC, WBC, Epithelial cells and Casts graded during microscopic analysis?
Scale 0-100, >100, Packed field
How are Bacteria, Crystals and mucous strands graded during microscopic analysis?
1+
2 +
3+
How are Spermatozoa and yeast graded during microscopic analysis?
Not Present (Do not indicate)
Present
What is a clean catch sample? why is this the idea way of collecting urine specimens?
- Midstream catch, requiring disinfection of the urethral opening prior to voiding
- Best for non contaminated specimens as well as routine and bacteriologic evaluation.
What do you call a sample collected through the insertion of tubing into the bladder to facilitate voiding?
- catheter specimens
What do you call a sample that has been collected by needle insertion into the distended bladder and for what reason would this be ordered?
- Suprapubic urine collection
- Useful for children and infants
- avoids contamination from urethra and vagina
What are four common preservatives used on urines?
- Boric acid
- HCL
- Chlorhexidine
- Formalin
What kind of urine is best for the determination of pregnancy in terms of specimen preservation?
Un preserved
You’ve received a urine sample in the lab and set it down on the bench behind you, your charge tech approaches you with a list of stat orders from emerge he needs you to run immediately. After a few hours you realized you forgot to run the urine that you left on the bench. What results do you expect to see when you finally run the urine?
Inaccurate results because
- formed elements have deteriorated
- bilirubin and urobilinogen are unstable = untestable
- Glucose is decreased due to bacteria
- lysis of the cells
- increased pH
What are 3 reasons a urine might be abnormal?
- Medication
- diet
- disease
What are reasons for a pale coloured urine?
dilute
diuretics
What are reasons for a red urine?
blood
hemoglobinuria
myoglobinuria
What are reasons for a brown or black urine?
RBC
Heme pigments
age/pH
What are reasons for a Yellow- green urine?
bilirubin metabolism
What does the presence of foam in a urine sample indicative of?
high protein