exam II Flashcards
how does the pH of urine relate to it’s hydrogen ion concentration?
it’s an inverse relationship
increased hydrogen ion : decreased pH
decreased hydrogen ion : increased pH
Ketone bodies in the urine are suggestive of elevated _____ metabolism
fat
what causes myoglobinuria?
extensive muscle injury
what is the general purpose of test strip screening?
immediate answer to whether or not pathological concentrations of substances are present in the urine
what color is a (+) positive nitrate on the dipstick?
pink
what substance is most likely to be present in urine that could cause a false (=) negative reaction on the dipstick for glucose?
ascorbic acid or vitamin C
what is SSA used for?
confirmatory test for proteins
what test is used for detecting reducing sugar in the urine?
clinitest
what would be expected in the microscope examination, if reducing sugars are detected?
nothing
what two dipstick reactions are usually (+) positive in pyelonephritis and cystitis?
leukocytes and nitrates
name several conditions that could be indicated by an elevated urinary urobilinogen
hepatitis & cirrhosis
hemolytic anemia
pernicious anemia
name several conditions that can cause hemoglobinuria
extensive burns
incompatable blood transfusions
what is specificity (as related to dipstick reactions)?
each test zone should react specifically to the substance being test and to no other
the test pad for ketone bodies detects _____?
acetoacetic acid
what is the principle of the dipstick method for protein?
protein of error indicators:
-tetrabromphenol blue buffered at a constant pH 3 without proteins is yellow, but in the presence of proteins, hydrogen ions are released by indicator dye causing color changes ranging from yellow-green to blue-green
what unusual urinary protein is associated with multiple myeloma?
bence-jones
50% of patients have this
what sugar (especially in infants) is most likely indicaated by a (=) dipstick reaction for glucose but a (+) clinitest?
galactose
what specimen is used to detect orthostatic proteinuria?
2 specimens:
first morning and a second after the patient has been upright for a few hours
what is the active ingredien in ehrlich’s reagent?
P-dimethylamino-benzaldehyde
what is the reagent used to detect bilirubin in the icotest?
2,4 dichlorobenzene diazonium tetrachlorozincate
the reagent strip for hemoglobin detects ___,___&___
hemoglobin
myoglobin
RBC
what is the action of the enzyme peroxidase?
to catalyze the oxiation of chromogen (3,3,5,5 tetramethyl benzidine) by the O2 released from peroxidase on reagent pad to produce a color changing from yellow-green
pseudo peroxidase activity
why is there normally no glucose in the urine?
because it is absorbed in convoluted tubules
what is the advantage of using phase contract microscopy in the examination of urinary sediment?
allows to see unstained cellular components and casts
how does the phase contrast microscope relate to the refractive index?
the refractive index (mucus, hyaline casts) is the same as urine making them hard to see
what is the use of the polarizing microscope in urine microscopics?
lipid material and crystals
cells are recorded as number per __ power field (__x)
high
40
how many field should be expmined in a microscopic exam?
10
what is the most common type of WBC found in the urinary sediment?
neutrophils
casts in urine are usually accompanied by a (+) test for what
protein
casts containing cells indicate problems in what part of the urinary tract?
kidneys
where are transitional epithelial cells found?
bladder, renal pelivs , 2/3 male urethra
amorphous phosphates are found in urine of what pH?
alkaline
what disease is indicated when tyrosine and leucine are found in the urine?
severe liver disease
nephrotic syndrome is characterized by
proteinuria and lipiduria
casts which have at least two distinct components are called
mixed casts
casts should be reported as the number per ___ power field (_-x)
low
10
which WBC is most likely to be found in a transplant rejection
lymphocyte
in what specific portions of the nephron are casts formed?
lumen of DCT and collecting ducts
what specific type of epithelial cells are found in epithelial cell casts
renal tubular epi. cells
in what type of diseases (in general) are RBC casts found?
basement membrane ducts of glomerulus has been damaged
glitter cells are associaed with urine of ___ specific gravity
low
what type of epithelial cells are indicative of vaginal contamination?
squamous
calcium oxalate crystals are normally found in __ pH urine
acidic
what condition is indicated by large numbers of uric acid crystals?
gout
candida albicans (a yeast) is often found in the urine of patients with __________
diabetes mellitus
if flat, hexagonal, colorless crystals are found in the ruine what constituent s suggested?
cystine
what should the technologist do prior to reporting out cystine crystals?
chemical confirmation for cystine
how can RBC and yeast be differentiated?
acetic acid will lyse RBC’s not yeast.
what is the appearance of waxy casts?
waxy, highly refractive, colorless or gray-yellow uneven ends, cracks/fissures
name several organisms whose urinary presence indicates contamination?
- RBC’s with no casts , proteinuria (menstrual/ hemorrhoidal)
- squamous
- sperm
- parasites
the order for the aging process of casts is ….
cellular,
coarsely granular
finely granular
waxy
what is the term for the presence of elevated numbers of casts in urine?
cylinduria
how can a precipitate of amorphous phosphate be removed?
soluble in dilute acetic acid
how can a precipitate of amorphous urates be removed?
heated to 60C / dissolved in alkali
what would be the appearance of RBC in hypertonic urine?
crenated
can the multistix detect a negative urobilinogen?
no
how would you interpret a (=) nitrate but a (+) bacteria?
- bacteria cannot convert NO3 to NO2
- no nitrates in diet
- urine hasn’t been in bladder long enough
- so much bacteria that it further reduces NO3 to N2
what happens if you dip the reagent strip too much?
leeching or run over of reagents
what type of casts may be formed in the urine of a normal pH?
hyaline
what are shadow cells?
RBC that have lost HB
what is the significance of the shape and size of a cast?
shape and size aid in ID
urine for testing should be at ___ temperature
room
why do we use the refractometer for specific gravity rather than the dipstick?
because the refractometer can detect ionic and nonionic solutes
how does the watson-schwartz test differentiate between urobilinogen and porphobilinogen?
urobilinogen is solube in chloroform and butenol
porphobilinogen is soluble in the aqueous layer
what is the principle of the automated instruments for dipstick reading?
reflectance photometrey
glucose in the urine is referred to as ___ or ___
glucosuria
glycosuria
the two different forms of blood in the urine are described as ___ and ___
hemoglobinuria
hematuria
what reagent is used to differentiate urinary hemoglobin and myoglobin?
80% ammonium sulfate ( precipitates out hemoglobin)
what is the normal range for urinary urobilinogen?
0.1 - 1
which test is the most sensitive for bilirubin?
icotest
what is ketonuria?
ketones present in urine
what symptoms would make you suspect the patient is suffering from orthostatic proteinuria
children and adolescence who have proteinuria
what are some possible causes of hematuria?
kidney stones glomerulonephritis pyelonephritis trauma strenuous exercise smoking
ketones
sodium nitroprusside
urobilinogen
para-dimethlyaminobenzaldehyde
protein
tetrabromphenol blue
pH
bromthymol blue
methyl red
nitrite
1,2,3,4-tetrahydrobenzoquinoline-3-olpara-arsanilic acid
bilirubin
2,4-dichlorobenzenediazonium tetrachlorozincate (aka-diazotized 2,4-dichloroaniline)
glucose
glucose oxidase gluconic acid hydrogen peroxide potassium iodide peroxidase
blood
3,3,5,5-tetramethylbenzidine hydrogen peroxide
