AUBF (Macro, Chem, Micro) Flashcards
Included in PHYSICAL examination of urine
Color
Clarity
SG - now included in rgt strip
pigment present in urine that gives a yellow color (Thudichum)
Urochrome (normal pigment)
pink pigment, most evident in spx that have been REFRIGERATED, resulting in precipitation of AMORPHOUS URATES
uroerythrin
result of uroerythrin + urates in ACIDIC pH
pink urine sediment
oxidation product of UROBILINOGEN (normal urinary constituent), imparts an orange-brown (amber) color to urine that is NOT FRESH (longer standing)
Urobilin
pigment that may also be an indicator of hemolysis if extremely increased
checked: urobilinogen, bilirubin
urobilin
urine with amorphous urates in ACID pH
forms PINK precipitate
urine with amorphous phosphates in ALK pH
white precipitate
urine color:
oxidation of porphobilinogen to porphyrins
red
portwine
urine color:
heme biosynthesis problem —> porphyrias (enzyme deficiencies)
red
portwine
urine color:
melanoma
alkaptonuria
black
oxidation of melanogen (colorless pigment) to melanin (black pigment) - produced in excess
MELANOMA
condition with excreted BLACK urine
melanoma
(not alkaptonuria - only imparts black color during standing)
condition excreted as normal urine color and became BLACK during standing
alkaptonuria
homogentisic acid (metabolite phenylalanine) - imparts black color to ALK urine from person with inborn metabolism
alkaptonuria
metabolic problem in BABIES
inc pH (alk)
alkaptonuria
urine color:
pseudomonas inf
green
(pyoverdin)
urine color: clorets
blue-green
(pyocyanin)
what must be done before assessing urine clarity
MIX WELL
Reporting of urine clarity
Clear
Hazy
Cloudy
Turbid
Milky
Urine clarity:
no visible particulate
transparent
clear
Urine clarity:
FEW particulates,
print easily seen
hazy
Urine clarity:
MANY particulates,
print blurred
cloudy
Urine clarity:
print cannot be seen
turbid
Urine clarity:
may precipitate or be clotted (egg white-like) may be due to inc. lipid profile
milky
non-pathologic cause of urine TURBIDITY
squamous EC (contaminated collection)
mucus
amorphous phosphates, urates, carbonates
RCM
talcum powder
semen, spermatozoa
fecal contam
vaginal creams
pathologic cause of urine TURBIDITY
RBC
WBC
Bacteria
Yeast
Non-squamous EC (RTE cells)
Abnormal crystals
Lymph fluid (chyluria)
Lipids
differentiate hematuria from hemoglobinuria
hematuria: intact RBC microscopically
hemoglobinuria: hemolyzed RBC microscopically
eval of urine conc. (solutes present in urine)
SG
random urine sample SG
1.015-1.030
determine whether spx conc. is adequate to ensure chem test accuracy
SG
SG of water
1.000
SG of RCM
1.040
(differential to chole crystals)
SG: isosthenuric
1.010
SG: hyposthenuric
<1.010
SG: hypersthenuric
> 1.010
Current urine SG measurement methods
Refractometry
Osmolality
Reagent strip
principle of Refractometry
refractive index (read intersection betw. blue and white portion)
principle of Osmolality
changes in colligative properties by particle no.
principle of reagent strip
pKa changes of polyelectrolyte by ions present
Methods for manual SG measurement
Refractometer
Urinometer
measurement that requires temperature adjustment
urinometer
(5/9 ; F -32)
measurement that requires NO temperature adjustment
refractometer
calibration of manual SG measurement
subtract 0.003 for every 1 g of PROTEIN
subtract 0.004 for every 1 g of GLUCOSE
MACROSCOPIC screening for BLOOD seen microscopically
color
MACROSCOPIC screening for hematuria vs hemoglobinuria/myoglobinuria and pathologic and nonpathologic cause of turbidity seen microscopically
CLARITY
aka myoglobinuria
rhabdomyolysis
Hemoglobinuria vs. Hematuria vs. Myoglobinuria
Hemoglobinura: CLEAR, red
Hematuria: TURBID, red
Myoglobinuria: coca-cola like
MACROSCOPIC/CHEM SCREENING TEST for RBC, RBC casts seen microscopically
Blood
MACROSCOPIC/CHEM SCREENING TEST for casts and cells seen microscopically
protein
MACROSCOPIC/CHEM SCREENING TEST for bacteria and WBCs
nitrite
MACROSCOPIC/CHEM SCREENING TEST for WBCs, WBC cast, bacteria
Leukocyte esterase
(has the longest reading time - 120s)
MACROSCOPIC/CHEM SCREENING TEST for yeast seen microscopically
glucose
glucose in urine
glucosuria (ex. presence of yeast)
INCREASED
CHANGES IN UNPRESERVED URINE
“p(a)BaON”
- pH (alk)
- bacteria
- odor (ammoniacal)
- nitrite
DECREASED
CHANGES IN UNPRESERVED URINE
clarity
glucose
ketones
bilirubin
urobilinogen
RBCs, WBCs, Casts
Trichomonas
what happen to urine COLOR during long standing (unpreserved)? reason?
modified/darkened
Reason: oxidation or reduction of metabolites (urobilinogen —> urobilin “amber”)
what will happen to CLARITY during long standing of unpreserved urine?
reason?
turbid (decreased)
reason: bacterial growth and precipitation of amorphous materials
what will happen to GLUCOSE during standing in unpreserved urine? reason?
decreased
reason: glycolysis, bacterial use
what will happen to KETONES during standing in unpreserved urine? reason?
decreased (highly volatile, requires freshly voided urine for accurate measurement)
reason: volatilization, bacterial metabolism
what will happen to BILIRUBIN during standing in unpreserved urine? reason?
decreased
Reason: light exposure, photo oxidation to biliverdin
what will happen to UROBILINOGEN during standing in unpreserved urine? reason?
decreased
Reason: oxidation to urobilin “amber”
what will happen to RBC, WBC, casts during standing in unpreserved urine? reason?
decreased
Reason: disintegration in dilute ALK urine
what will happen to TRICHOMONAS during standing in unpreserved urine? reason?
decreased
Reason: loss of motility, death (if disintegrated, resembles WBC)
loss of motility and disintegration of trichomonas resembles?
WBCs
what will happen to ODOR during standing in unpreserved urine? reason?
increased (ammoniacal)
Reason: bacterial multiplication (urea —> ammonia)
what will happen to pH during standing in unpreserved urine? reason?
increased (alk)
reason: breakdown of urea to ammonia by urease-producing bacteria or CO2 loss
ex: alkaptonuria
what will happen to NITRITE during standing in unpreserved urine? reason?
increased
Reason:
- multiplication of NITRATE- reducing bacteria
- bacterial contamination
what will happen to BACTERIA during standing in unpreserved urine? reason?
increased
Reason: multiplication
cause of AROMATIC urine odor
NORMAL!!
cause of FOUL, AMMONIA-LIKE urine odor
Bacterial decomposition
UTI
cause of FRUITY SWEET urine odor
Ketones (Starvation, DM, Vomiting)
cause of MAPLE SYRUP urine odor
MSUD (inborn error of metabolism)
cause of MOUSY urine odor
Phenylketonuria (PKU)
cause of RANCID urine odor
tyrosinemia
cause of SWEATY FEET urine odor
isovaleric acidemia
cause of CABBAGE urine odor
Methionine malabsorption
cause of BLEACH urine odor
Contamination
cause of ROTTING FISH urine odor
trimethylaminuria
“galunggong-like” odor
Benedict’s test is only appropriate for?
glucose and other reducing sugars (except SUCROSE - nonreducing)
Principle of benedict’s test
Copper reduction
Benedict’s test reaction
Cupric ions (Cu2+) + reducing sugar —heat + alkali –> carboxylic acid + Cuprous oxide (Cu2O)
Cupric ions - blue solution
reducing sugar - in urine
Cuprous oxide - indicator that gives brick red ppt
ratio of benedict’s soln to urine
1:1