Chapter 3: Urinalysis Exam 2 Flashcards
Confirmatory test for Bilirubin
Ictotest
Clinitest
- Detects all reducing substances (other sugars)
- Multistix detects only glucose
- Can be used to correlate with Multistix test for possible detection of Galactosemia, a congenital deficiency in the body’s ability to metabolize galactose to glucose; when seen in infants, can result in failure to thrive
Hematuria
Red blood cells in the urine
What results could be positive on a reagent strip to indicate a UTI?
- Protein
- Leukocytes
- Blood
- Nitrites
What results could be positive if a patient has diabetes mellitus?
- Glucose
- Ketones
Acetest
Confirmatory test for Ketones
What does the presence of nitrites indicate in fresh urine?
Bacteria
Positive erythrocytes in urine could be an indication of?
Kidney Stones
Sometimes tumors/lesions
Reagent strips are defined as this….
Qualitative & Semiquantitative urine tests
Qualitative
Indicates whether a particular analyte is present
Quantitative
measures the exact amount of a substance
Semiquantitative
determines the approximate quantity of an analyte
Amorphous
Shapeless clumps/without shape or definite shape
What objectives are used to view microscopic urines?
Lower Power Field-10x
High Power Field- 40x
Supernatant
Liquid portion of urine on top of the spun sediment
Sediment
Material at the bottom of the centrifuge tube of urine
Crystals
Are formed by the precipitation of urine salts when changes in pH, temperature, or concentration occur
the most important aid in the identification of urine crystals
pH
Crystals are counted on ____ and identified under ______ and reported as few, moderate, and many
- counted on LPF
- identified under HPF
Abnormal crystals may represent disorders such as
- liver disease
- inborn errors of metabolism
- or renal damage caused by the crystallization of iatrogenic compounds (caused by treatment or diagnostic procedures).
Procedure for preparing urine for microscopic examination
- put 12 mL in centrifuge tube
- 5 mins in centrifuge
- Take it out after 5 mins and pour off supernatant
- Mix up sediment
- Put into 10 slides
Casts
- formed primarily within the lumen of the distal convoluted tubules and collecting ducts
- Provide a microscopic view of conditions within the nephron
- Shapes usually contain parallel sides and rounded ends
Four factors can lead to cast formation…..
- decreased urine flow
- increased acidity (low pH)
- increased solute concentration (high specific gravity)
- increased plasma protein
Types of casts
- Hyaline Casts
- Red Blood Cell Casts
- White Blood Cell Casts
- Renal Epithelial Cell Casts
- Granular Casts
Positive bilirubin test strips could be caused by what liver diseases?
Jaundice and Hepatitis
Pyuria
White Blood Cells in the urine
squamous epithelial cells
not clinically significant usually
what are examples of artifacts/contaminants?
- Hair
- Fecal matter
- Diaper fibers/clothing fibers
- Pollen Grains
- Air bubbles
what is is the most frequently seen parasite in urine specimens?
Trichomonas vaginalis
What is trichomonas vaginalis?
a sexually transmitted parasite that causes vaginal inflammation in women and infection of the urethra and prostate in men
What is yeast?
Are small, oval organisms that may bud and form hyphae (branches)
What word is associated with yeast that distinguishes it from red blood cells?
Budding
To know about bacteria
- Quality of collection of specimen (midstream clean catch)
- Are very tiny and must be viewed on high power
- Appear as either rod shaped (bacilli) or round (cocci) or amorphous (without definite shape)
- Are reported as few, moderate, or many or as 1+, 2+, 3+, or 4+
What will show up when bacteria is detected?
Elevated nitrite will show up (patient has infection)
erythrocyte
red blood cells
WBC description
WBCs have a visible nucleus, and their cytoplasm may appear granular and coarse. They are reported as cells per HPF
Presence of WBCs can be a factor in ….
pyelonephritis, cystitis, prostatitis, and urethritis
what is the most common WBC found in the urine?
neutrophils
Renal Tubular epithelial cells can indicate……
pyelonephritis, toxic reaction, viral infection, allograft rejection, and secondary effects of glomerulonephritis
RBCs definition
RBCs are round, biconcave, no nucleus, colorless disks.
Counted and reported as cells per HPF.
Guidelines when using reagent test strips…
- Reagent strip bottle must be kept tightly closed.
- Pads on strip should not be touched.
- Do not refrigerate strips; keep in cool, dry place.
- Don’t use expired strips.
- Do not combine strips from different bottles.
- Follow all directions from the manufacturer.
- Make sure all pads are covered with urine
Specific Gravity
The weight of urine as compared to an equal volume of water
What does SG measure in urine?
measures the the amount of particles that are dissolved in the urine, which indicates the ability of the kidneys to concentrate the urine
which specimen is specimen is usually the most concentrated?
First morning
The normal range for urine S/G is…
1.003 to 1.030, but the range is usually between 1.010 and 1.025.
what is pH?
Scale from 0-14, measures the level of acidity or alkalinity in the urine
pH of 7 is?
neutral
pH of 0 to 6 is….
acid
pH of 8 to 14 is…
alkaline
Normal urine has a pH of….
5.0-8.0
why should you use freshly voided urine to measure pH?
because bacteria in the urine will convert urea to ammonia causing the urine to become alkaline.
If freshly voided urine is alkaline what may it indicate?
UTI
Glucose is…
The most common sugar
Glycosuria occurs when…
blood glucose levels are so high that renal tubule glucose cannot be reabsorbed back into the blood and the renal threshold is reached
The presence of glucose in the urine may be an indication of
diabetes mellitus
vigorous exercise
emotional stress
Ketones
Products of fat metabolism that are then oxidized by the muscles
ketonuria
The excess ketones accumulate in tissues and blood and subsequently in the urine
Ketones and glucose in the urine may be associated with
uncontrolled diabetes mellitus
Other conditions producing ketones in urine without the presence of glucose
- Anorexia and starvation
- Diets high in fat and low in carbohydrates
- Prolonged vomiting
- Fever
What is bilirubin produced from?
the breakdown of hemoglobin
what color is bilirubin?
yellow pigment
where does bilirubin become urobilinogen?
small intestine
where does bilirubin become water soluble?
the liver
Conditions that cause excessive blood levels of bilirubin are
Excessive hemolysis Hepatitis Liver damage, Liver sclerosis Obstructive jaundice Obstruction of the bile duct
Bilirubin gives a _______ color (jaundice) to the urine, plasma, skin, mucous membranes, and whites of the eye (sclera).
yellow-orange
what does urobilinogen result from?
results from a breakdown of bilirubin in the colon by bacteria.
what does urobilinogen give color?
feces
Conditions that can cause increased levels of urobilinogen in the urine are
Excessive hemolysis of RBCs
Cirrhosis
Infectious mononucleosis
Congestive heart failure
Three substances can cause pad to be positive for blood
- Intact red blood cells
- Hemoglobin from lysed red blood cells
- Myoglobin (Oxygen-storing pigment of muscle tissue, can be found in urine after massive muscle injury, physical trauma, or electrical injury.)
Hemoglobinuria can be caused by
transfusion, reactions, malaria, drug reactions, snake bites, and severe burns.
Blood in urine usually occurs from…
- UTIs associated with bleeding, such as cystitis and urethritis.
- Kidney stones, tumors, and lesions may cause bleeding.
Protein
Small amounts are normal in urine
proteinuria
A large amount of protein in the urine
what is one of the the first signs of renal disease?
proteinuria
What specimen is best for testing for nitrites?
First morning specimen is best because urine must remain in the bladder a minimum of 4-6 hours for nitrates to be changed to nitrites
What is usually indicated by the presence of leukocytes in the urine?
UTI
