M3U4: LEUKOCYTE ESTERASE, NITRITE, AND ASCORBIC ACID

Question 1

Ascorbic acid is more commonly known as

Answer 1

vitamin c

Question 2

Ascorbic acid is __ thus can be easily reabsorbed and excreted in urine

Answer 2

water-soluble

Question 3

what is the metabolite of ascorbic acid ?

Answer 3

oxalate

Question 4

Ascorbic acid functions as an ___ in ___

Answer 4

enzyme cofactor

connective tissue proteins

Question 5

Ascorbic acid is considered as a __ capable of donating hydrogen ions and readily oxidizes to dehydroascorbic acid

Answer 5

strong reducing substance

Question 6

what is the colour of dehydroascorbic acid ?

Answer 6

colourless

Question 7

chemical tests that involve ___ and ___ is prone to ascorbic acid interference

Answer 7

hydrogen peroxide

diazonium salt

Question 8

What pads on the reagent strip does ascorbic acid interfere with ?

Answer 8

blood, bilirubin, nitrite, and glucose

Question 9

Interference of ascorbic acid on the reagent strip is evident when the expected colour change does not occur, resulting to __

Answer 9

false-negative or falsely low result

Question 10

Reagent pad for blood is based on the ___ where it reduces the hydrogen peroxide impregnated in the reagent pad and oxidizes the chromogen

Answer 10

pseudoperoxidase activity of heme moiety

Question 11

In the reagent pad for blood, if ascorbic acid is present what happens ?

Answer 11

reaction does not take place since ascorbic acid reacts to the hydrogen peroxide instead

Question 12

Ascorbic acid at ___ interferes with the glucose reagent pad

Answer 12

> 50 mg/dL

Question 13

How does ascorbic acid interfere with the glucose reagent pad reading ?

Answer 13

it reacts to the hydrogen peroxide produced in the first reaction and inhibiting the second reaction which involves the development of colour on the reagent pad

Question 14

Ascorbic acid at ___ interferes with the bilirubin reagent pad

Answer 14

> 25 mg/dL

Question 15

How does ascorbic acid interfere with the bilirubin reagent pad reading ?

Answer 15

it reacts with the diazonium salt impregnated on the reagent pad, inhibiting the formation of a colour change

Question 16

This is characterized by the infection in the lower urinary tact involving the urethra

Answer 16

urethritis

Question 17

This is characterized by the infection in the lower urinary tract involving the bladder

Answer 17

cystitis

Question 18

This is characterized by the infection in the upper urinary tract involving the renal pelvis and tubules

Answer 18

pyelonephritis

Question 19

This may result from the movement of bacteria from the urethra into the urinary bladder

Answer 19

ascending infection

Question 20

___ are the more prevalent type of UTI

Answer 20

ascending infection

Question 21

ascending infections is commonly caused by ___

Answer 21

enteric gram-negative organisms like:
Escherichia coli
Proteus species
Enterobacter species
Klebsiella species

Question 22

Normally, a few white blood cells are present in urine at ___

Answer 22

0-8/HPF or 10 WBC/uL

Question 23

An increase of WBC at ___ is a possible indicator of inflammation anywhere along the urinary tract and kidneys

Answer 23

≥ 20 WBC/uL

Question 24

Why is leukocyturia often used in conjunction with bacteriuria in the assessment of urinary tract infections ?

Answer 24

increase in WBC is a possible indicator of inflammations along the urinary tract and kidneys and with ascending infection as the most prevalent type of UTI is commonly caused by enteric gram-negative organisms

Question 25

What nonbacterial conditions can leukocyturia be observed in ?

Answer 25

acute interstitial nephritis

polycystic kidney

infection caused by other organisms:
mycoses
Trichomonas vaginalis
Chlamydia trachomatis

Question 26

Leukocyte esterases are enzymes found in ___

Answer 26

azurophilic granules of granulocytes (neutrophils, eosinophils, and basophils)

monocytes

macrophages

Question 27

How are urinary nitrites formed ?

Answer 27

result of diet or bacterial conversion of nitrate