CHEMICAL EXAMINATION OF URINE (LEUKOCYTES)

(leukocyte esterase) (microscopic examination)

LEUKOCYTES

(italicized words are from senior notes)

● Uses (______________) reaction

● Prior to reagent strip LE test: detection of increased

urinary leukocytes required (________________).

● Subjected to variation depending on the method used to

prepare the sediments and technical personnel studying

the sediment. They must be proficient when performing

the microscopic examination for the presence of the

leukocytes

● Additional advantage of the chemical leukocyte esterase

test is that it can detect the presence of leukocytes

that have been lysed, especially in alkaline urine /

dilute alkaline urine. This will not appear in microscopic

examination because these leukocytes have been lysed.

(LEUKOCYTE ESTERASE) (Neutrophils) (Basophils) (Eosinophils) (Monocyte) (Macrophages) (azurophilic granules or primary granules) (LYMPHOCYTES)

(_______________)

● Found in white blood cells, specifically granulocytic

cells:

○ (_________)

○ (_________)

○ (_________)

○ (___________)

○ (__________)

● Found in the (___________/_________) of the granulocytes.

● It is important to know that these does not include the

(________________) because they are not granulocytes.

(Urinary tract infection (UTI) (UTI) (vaginal discharge) (false-positive result) (granulomatous WBCs) (trichomonas) (histiocytes (liver macrophages)) (erythrocytes, bacteria and renal tissue) (positive nitrite) (Leukocyturia) (Trichomonas) (Chlamydia) (Yeast) (interstitial nephritis)

CLINICAL SIGNIFICANCE

● For patients with (_______________)

● Higher incidence of (_______) is found more commonly in

women than in men

● Women can also give a positive result in leukocyte

esterase (even when they don’t have UTI) due to

contamination of (________)

o It can give a (____________)

o It is important to ask the patient how did they collect

their sample if it is positive in leukocyte esterase

● Leukocyte esterase (LE) test detects esterases which

are found:

○ in the (__________)

○ in (__________)

○ in (________________)

● Lymphocytes, together with (________, _______, ______) cells DO NOT contain esterases

● The presence of bacteria may or may not give a (________) result

● (____________) (presence of leukocyte in the urine) can be

caused with:

○ (__________)

○ (____________)

○ (____________)

○ Inflammation of the renal tissue in the (__________)

(Indirect detection) (120) (2) (indoxylcarbonic acid

ester) (diazonium salt) (purple azodye) (Trace, Small, Moderate, Large)

REAGENT STRIP METHOD

● (___________) of the presence of UTI-causing

bacteria in the urine (bacteriuria)

○ This test is NOT designed to measure the

concentration of leukocytes. We will still rely on the

Microscopic Examination for the computation of the

leukocytes present in the urine.

Reading time:	(_____) seconds ● When you test using the reagent strip method, you have to wait for at least (___) minutes, because maybe, there is a delayed reaction for the leukocyte esterase in the sample of the urine of the patient.
Principle:	● The action of leukocyte esterase found in the granulocyte would catalyze the acid-ester present there, which is the (_____________) that is impregnated on the reagent pad to produce an aromatic compound and acid ● The aromatic compound and acid would combine with the (____________) in the presence of an acid medium to produce a (__________) ● Positive result for the reagent strip method: (6) (_______)
Reporting:	(______, _____, _____, _____)

(Oxidizing agents) (High concentration of CHONs (>500 md/dl)) (Formalin) (Glucose (>3 mg/dl)) (Highly pigmented urine) (Oxalic acid) (Nitrofurantoin) (Ascorbic acid) (Crenation of leukocytes) (Gentamicin) (Cephalexin) (Cephalothin)

(Tetracycline)

REACTION INTERFERENCE

FALSE POSITIVE (+)	FALSE NEGATIVE (-)
(_____________)	(_____________)
(______________)	(_____________)

(____________)	(__________)
● May obscure the color reaction of the leukocyte esterase reagent pad
(_____________) ● Is an antibiotic that may obscure the color reaction of the leukocyte esterase reagent pad	(____________) ● Combines with diazonium salt (_________) ● The presence of (8) (___________) prevents release of esterases. ● May occur in urines with high specific gravity (_________) (_________) (_________) (__________) ● The presence of these antibiotic decreases the sensitivity of the reaction for the leukocytes.