heme externship - UA 7.1 Flashcards
which statement regarding renal function is true?
A. Glomeruli are far more permeable to H2O and salt compared with other capillaries
B, the collecting tubule reabsorbs sodium and secretes potassium in response tp ADH
C. the collecting tubule is permeable to H2O only in the presence of aldosterone
D. the thick ascending limb is highly permeable to H2O and urea
A. Glomeruli are far more permeable to H2O and salt compared with other capillaries
which statement regarding normal sale and h2o handling by the nephron is correct
A. the thick ascending limb of the tubule is highly permeable to salt but not water
B. the stimulus for ADH release is low arterial pressure in the afferent arteriole
C. the descending limb of the tubule is impermeable to urea but highly permeable to salt
D. renin is released in response to high plasma osmolality
A.
which statement concerning renal tubular function is true?
A. in salt deprivation, the kidneys will conserve sodium at the expense of potassium
B. potassium is not excreted when serum concentration is less than 3.5mmol/L
C. no substance can be excreted into the urine at a rate that exceeds the glomerular filtration rate (GFR)
D. when tubular function is lost, the sp gravity of urine is below 1.005
A.
- sodium is a threshold substance - it will not be excreted until plasma levels are 120 mmol/L
- potassium is always lost a little bit
which of the following is inappropriate when collecting a urine for routine bacteriologic culture
A. the container must be sterile
B. the midstream void technique must be used
C. the collected sample must be plated within 2 hours unless refrigerated
D. the sample may be he;kd at 2C to 8C for up to 48 hours prior to plating
D.
which statement about sample collection for routine urinalysis is true
A. preservative tablets should be used for collecting random urine specimens
B. containers may be washed and reused if rinsed in DI water
C. samples may be stored at room temp for up to 2 hours
D. a midday sample is preferred when renal disease is suspected
C.
which urine color is correlated correctly with the pigment-producing substance
A. smoley red urine with homogentisic acid
B. dark amber urine with myoglobin
C. deep yellow urine and yellow foam with bilirubin
D. red brown urine with biliverdin
C.
- homogentisic= black
- myoglobin = red
- biliverdin = green
which of the following substances will cause urine to produce red fluorescence when examined under a UV lamp
A. myoglobin
B. porphobilinogen
C. urobilin
D. coproporphyin
D.
- porphobili = dark brown
- uroporphyrin and coproporphyrin = fluoresece
which of the following conditions is associated with normal urine color but produces red fluorescence when urine is examined with a UV (Wood) lamp
A. acute intermittent porphyria
B. lead poisoning
C. erythropoietin porphyria
D. porphyria cutanea tarda
B.
- lead poisoning blocks heme synthesis = increase in prophobilinogen and coproporphyrin, enough to cause a fluorescence
which statement regarding porphyria is accurate
A. porphyria is exclusively inherited
B. all types cause an increase in uriany porphyrins
C. all types are associated with anemia
D. serum, urine and fecal tests may be needed for diagnosis
D.
which is the most common form of porphyria
A. erythropoietic
B. acute intermittent
C. variegated
D. porphyria cutanea tarda
D.
- can be seen with hep infection
which of the following methods is the least sensitive and specific for measuring PBG in urine
A. Watson schwartz test
B. LC-MS
C. ion exchange chromatography - Ehrlich reaction
D. isotope dilution - MS
A.
- qualitative screening, others are diagnostic
a brown or black pigment in urine can be caused by:
A. pyridium
B. PSP
C. rifampin
D. melanin
D. melanin
urine that is dark red or port win colored by be caused by
A. lead poisoning
B. porphyria cutanea tarda
C. alkaptonuria
D. hemolytic anemia
B. PCT
which of the following tests is affected the least by standing or improperly stored urine
A. glucose
B. protein
C. pH
D. bilirubin
B. protein
- becomes more alkaline as standing
- glucose consumed by oxidation
- bilirubin converted to biliverdin
which one of the following characteristics would be a reason for performing a microscopic examination of urinary sediment
A. high vol
B. color intensity
C. turbidity
D. specimen from a foley catheter
C. turbidity
- inspect why
which of the following is appropriate when collecting a 24 hour urine sample for metanephrines
A. urine in the bladder is voided at the start of the test and added to the collection container
B. at 24 hours any urine in the bladder is voided and discarded
C. all urine should be collected in a single container that is kept refrigerated
D. ten milliliters of 1N sodium hydroxide should be added to the container before collection
C.
- first urine is discarded
- last urine is added to the container
urine production of less than 400 mL a day is
A. consistent with normal renal function and water balance
B. termed isothenuria
C. defined as oliguria
D. associated with diabetes mellitus
C.
which of the following contributes to sp grav but not osmolality
A. protein
B. salt
C. urea
D. glucose
A.
- if it can dissolve it relates to osmolality
urine with an SG consistenly between 1.002 and 1.003 indicates
A. acute glomerulonephritis
B. renal tubular failure
C. diabetes insipidus
D. Addison disease
C.
in which of the following conditions is the urine SG likely to be below 1.025
A. diabetes mellitus
B. drug overdose
C. chronic renal failure
D. prerenal failure
C.
- drugs and glucose increase SG
- prerenal = tubules ok
which statement regarding the methods for measuring SG is true
A. refractometry is the most accurate way to determine dissolved solute concentration
B. colorimetric SG test results are falsely elevated when a large quantity of glucose is present
C. colorimetric SG readings are falsely low when pH is alkaline
D. refractometry should be performed before the urine is centrifuged
C.
what is the principle of the colorimetric reagent strip determination of SG in urine
A. ionic strength alters the pKa of a polyelectrolyte
B. sodium and other cations are cheated by a ligand that changes color
C. anions displace a pH indicator from a mordant, making it water soluble
D. ionized solutes catalyze oxidation of an azo dye
A. ionic strength alters the pKa of a polyelectrode
which statement regarding urine pH is true
A. a high protein diet promotes an alkaline urine
B. pH tends to decrease as urine is stored
C. contamination should be suspected if the urine pH is less than 4.5
D. bacteriruia is most often associated with a low urine pH
C.
in renal tubular acidosis, the pH of urine is:
A. consistently acid
B. consistently alkaline
C. neutral
D. variable depending on diet
B.
- defect in renal tubular re-abs of bicarb = waste of sodium bicarb and potassium bicarb = alkaline and hypokalemia associated with acidosis