Physical Examination Of Urine Test 2 Flashcards
Best practic analyze fresh or suitalbey preserved urine, usually refrigerated
1.Examine urine within 30 minutes of the collection, as the changes (decomposition) start
during this time.
2.Examine the urine in the first 1 to 2 hours of collection.
3.Urine is the best culture media for the growth of bacteria.
4.If it is delayed, then refrigerate the urine at 4 °C.
5.Urine left at room temperature >2 hours is not acceptable.
Urine samples to be rejected
1.When urine has incorrect preservatives.
2.When the urine quantity is insufficient.
3.When urine is not transported correctly.
4.When there is a missing or incomplete request form.
5.When urine has no proper identification.
6.When urine shows contamination like stool, etc.
Specimen integrity
Changes in urine composition take place not only in vivo but also in vitro
Test within 2 hours of collection
Refrigerate or chemically preserve if testing is delayed
Most problems are caused by bacterial multiplication
Increased: color, turbidity, pH, nitrite, bacteria, odor
Decreased: glucose, ketones, bilirubin, urobilinogen, RBCs, WBCs, casts
Physical changes in unpreserved urine
Color
color- oxidation or reduction of metabolites
Physical changes in unpreserved urine
Clarity
Decreased- Bacterial growth and precipitation of
amorphous material
Physical changes in unpreserved urine
Odor
Increased- Bacterial multiplication causing breakdown
of urea to ammonia
Physical changes in unpreserved urine
pH
Increased-Breakdown of urea to ammonia by urease-
producing bacteria/loss of CO2
Physical changes in unpreserved urine
Glucose
Decreased- Glycolysis and bacterial use
Macroscopic changes to unpreserved urine
Turbidity
Amorphous crystals may form
causing a pink color. Amorphous
crystals have no clinical significance
Smell - If urine is kept for a long time
at room temperature, it will give an
ammonia smell produced by the
bacteria, which will decompose the
urea in the urine
-erythrin gets deposited on amorphous crystals in a stored
urine specimen causing a pink or “brick dust appearanc
Microscopic changes in Unpreserved urine
Formed elements tend to disintegrate, especially in alkaline urine.
Formed elements are WBCs, RBCs, casts
Is this fluid urine
May be needed in drug screen collections or specimens collected
by needle aspiration
Urine creatinine concentrations 50 times higher than plasma
Urea, sodium (Na), and chloride (Cl) higher in urine than in other
body fluids
Physiologic range is 1.002 to 1.035 for urine specific gravity and
4.0 to 8.0 for pH
Urine from healthy persons contains no protein or glucose,
whereas many other body fluids do
Physical examination of urine includes
Color
Clarity
Specific gravity
Results provide
Preliminary information
Correlation with other chemical and microscopic
results
Physical characteristics
Preliminary information concerning
disorders such as
Glomerular bleeding
Renal tubular function
Liver disease
Inborn errors of metabolism
Urinary tract infection
Color of urine
Normal variations and Abnormal variation causes
- Ranges from colorless to black
- Normal variations caused by
– Normal metabolic functions
– Physical activity
– Ingested materials
– Pathologic conditions - Abnormal variations caused by
– Bleeding
– Liver disease
– Infection
normal urine
- Pale yellow, yellow, dark yellow
- Should be consistent within institution
Urochrome
Urochrome is pigment causing yellow color.
Urochrome is excreted at
darkens upon
- Excreted at a constant rate. More concentrated when
hydration is low resulting in darker urine. - Darkens upon exposure to light
Uroerythin and urobilin
- Uroerythrin and Urobilin are also normal pigments
found in urine. Uroerythrin is most evident when
deposited on amorphous crystals in a stored urine
specimen, causing a pink color or “brick dust” sediment.
Urochrome is pigment causing yellow color.
Dark yellow urine
- may be dehydrated
- may have high conversion of urobilinogen →urobilin
Amber or organe urine
- RBC breakdown in alkaline urine
- may have bilirubin (shake and look at foam)
- Formation of urobilinogen (normal component of urine but
photo oxidizes and turns yellow orange). No yellow foam. - Patient is taking phenazopyridine to relieve symptoms of
urinary tract infection
Pink urine
– oxidized porphobilinogen in patient with
porphyria if specimen has set out too long.
Amorphous crystal formation causes a light pink
color to form
Red urine
RBCs, hemoglobin, beets