CM - Microscopic Examination of Urine Diagram | Quizlet

Microscopic Examination of Urine

What is done to IDENTIFY insoluble substances

from blood, kidney, lower urogenital tract, and

external contaminants?

to DETECT and IDENTIFY

insoluble materials present in urine

What is the main purpose of

MICROSCOPIC EXAMINATION?

1. RBC

2. WBC

3. Epithelial cells

4. Bacteria

5. Yeast

6. Parasites

7. Mucus

8. Spermatozoa

9. Crystals

10. Artifacts

FORMED ELEMENTS

in the Urine

(10)

IDENTIFICATION and QUANTIFICATION

What is required to perform with urinary sediments

to considered its clinical significance?

1. METHODS by which sediments is prepared

2. VOLUME of sediments examined

3. METHODS and EQUIPMENT to obtain visualization

4. REPORTING MANNER

Several Procedural Variations in

MICROSCOPIC ANALYSIS

(4)

1. Macroscopic Examination

2. Chemical Examination

3. Microscopic Examination (Last)

Sequence of Examination

done in Urine (3)

1. Brightfield

2. Phase contrast

3. Polarized

Microscopic Methods (3)

Brightfield microscopy "Nomarski"

What is the microscopic method that is

most commonly used for urine sediment examination?

Phase-contrast microscopy (PCM)

What is the microscopic method that is used to

produce a phase difference of wavelength of light,

which gives "better contrast" when viewing

low refractive index sediments

Polarizing microscopy

What is the microscopic method that involves

the use of polarizing filters for observation of sediments that can ROTATE and REFRACT LIGHT

in two dimensions at 90'C?

1. Color

2. Clarity

3. Blood

4. Protein

5. Nitrite

6. Leukocyte-Esterase (LE)

7. Glucose

8. Patient population (ie. preg. women, pediatrics, geriatric etc.)

Significant Parameters/ Factors to consider

before performing MICROscopic Examination (7)

Blood

Identify MICROscopic significance

of MACROscopic examination of:

COLOR

1. Hematuria

2. Hemoglobinuria

3. Myoglobinuria

Identify MICROscopic significance

of MACROscopic examination of:

CLARITY

1. RBCs

2. RBC casts

Identify MICROscopic significance

of MACROscopic examination of:

BLOOD

1. Casts

2. Cells

Identify MICROscopic significance

of MACROscopic examination of:

PROTEIN

1. Bacteria

2. WBCs

Identify MICROscopic significance

of MACROscopic examination of:

NITRITE

1. WBCs

2. WBC casts

3. Bacteria

Identify MICROscopic significance

of MACROscopic examination of:

LEUKOCYTE ESTERASE

Yeast

Identify MICROscopic significance

of MACROscopic examination of:

GLUCOSE

FRESH and/or PRESERVED

What is the required conditions in specimen

for its examination?

1. RBC

2. WBC

3. Hyaline casts

What are the primary formed elements that

DISINTEGRATE RAPIDLY

particularly in dilute alkaline urine?

1. Amorphous urates

2. Amorphous phosphates

3. other nonpathologic crystals

What are the urinary sediments

that "PRECIPITATES" when refrigerated?

37'C

In what temperature does the specimens' "DISSOLVE" prior to centrifugation?

Midstream clean-catch specimen

What type of urine specimen MINIMIZES

external contamination of the sediments?

Dilute Random specimen

What type of urine specimen

may cause false-negative readings?

10 - 15mL

What is the standard amount of urine

collected for laboratory examinations?

Conical tube

In what type of tube do we centrifuge

the standard urine collected?

12 mL

What is the volume of urine to which

which multiparameter reagent strips

are EASILY IMMERSED?

NOTE the volume of specimen used'

in the report form

What should we do if it's not possible

to obtain a 12mL urine specimen?

Consistent

What is required in the

speed and length of time

set in centrifugation?

Relative Centrifugal Force (RCF) of 400

for under 5 minutes

What centrifugal force produces an

optimum amount of sediment

with the LEAST change of damaging the elements?

Relative Centrifugal Force (RCF)

What centrifugal force is used

to CORRECT for the differences in the diameter

of the centrifuge heads?

Use of NOMOGRAMS

How do we convert the units of

revolutions per minute (RPM)

to relative centrifugal forces (RCF)

in the laboratory?

RCF

= 1.118 x 10^-5 x radius in centimeters x RPM^2

FORMULA for converting the units of

revolutions per minute (RPM)

to relative centrifugal force (RCF)

Centrifugation calibration

What should be routinely performed

in centrifuges?

DISRUPTION of the sediments

prior to decantation

What would happen if

centrifugal braking mechanism is used

to SLOW the centrifuge?

0.5 - 0.1 mL

What is the volume of sediments

frequently used for microscopic viewing?

Concentration factor

= Urine Volume / Sediment Volume

FORMULA for Concentration factor

Sediment Concentration Factor

What relates to the probability of detecting

elements present in LOW quantities?

to QUANTITATE

the number of elements present

per milliliter

What is the purpose or use of

sediment concentration factor?

ASPIRATE the urine

(rather than poured off)

What should be done to "maintain"

a UNIFORM sediment concentration factor?

1. Urine aspiration

2. Sediment resuspension

3. Transfer of specimens to the slide

What are the purposes of pipettes

in SEDIMENT PREPARATION?

Gentle agitation

How should we thoroughly resuspend

the sediments?

1. USE of commercial-system pipette

2. REPEATED TAPPING of tip of the tube with finger

How is gentle agitation done

to thoroughly resuspend the sediment?

provides EQUAL DISTRIBUTION of ELEMENTS

in the microscopic examination fields

What is the significance of

"thorough resuspension" of sediments?

CONSISTENT

volume of sediment

What should be the volume of sediment

placed on the microscope slide for each

specimen?

20uL (0.02mL)

covered by 22 x 22mm glass cover slip

What is the recommended volume of sediment

to use in conventional glass-slide method?

LOSS of HEAVIER ELEMENTS

such as casts

What may happen if the specimen is

ALLOWED TO FLOW outside the cover slip?

1. Chamber volume

2. Size of viewing area

3. Approx. number of

LOW-POWER and HIGH-POWER viewing areas

What is supplied in the product literature

of commercial systems? (3)

1. Chamber volume

2. Size of viewing area

3. Approx. number of

LOW-POWER and HIGH-POWER viewing areas

4. SEDIMENT CONCENTRATION FACTOR

What are the necessary information

to QUANTITATE cellular elements per milliliter

of urine? (4)

1. KOVA

2. Urisystem

3. Count-10

4. Quick-Prep urinalysis system

5. CenSlide 2000 Urinalysis System

6. R/S Workstations 1000, 2000, 2003

What are the commercial systems available?

1. Capped, calibrated centrifuge tubes

2. Decanting pipettes to control sediment volume

3. Slides that control the mount of sediment examined

4. Produce a consistent monolayer of sediment for examination

5. Provide calibrated grids for more consistent quantitation

What are the advantages provided

by the commercial systems?

(5)

1. CenSlide

2. R/S Workstations

What commercial systems does

"NOT REQUIRE MANUAL LOADING" of the

centrifuged specimen onto a slide that "minimize" exposure to the specimen? (2)

CenSlide

What commercial system provides

designed tube that permits

DIRECT READING of the urine sediment?

R/S Workstations

What commercial system consist of a

glass flow cell into which urine sediment is

PUMPED, MICROSCOPICALLY EXAMINE and

FLUSHED from the system?

10x LPO

and

40x HPO

In what magnification power should the

microscopic examination of sediments

be observed?

10x Low Power Objective

What magnification power should

we used FIRST in examining the sediment?

1. Casts

2. Ascertain the general composition of sediment

What is the significance of observing in

10x LOW POWER OBJECTIVE?

when elements such as casts

REQUIRES an IDENTIFICATION

When do we only use

HIGH POWER OBJECTIVES

in examination of sediment?

if the conventional glass-slide method is being used

and casts have tendency to be located at the

"NEAR THE EDGES" of the cover slip

When do we use

LOW POWER OBJECTIVES

in examination of sediment?

Examine under REDUCED LIGHT

How do we essentially examine an

unstained sediments when using

bright-field microscopy?

unstained sediment's constituents have

a refractive index SIMILAR TO urine

Why do we need to examine the unstained sediments

under reduced light when using

bright-field microscopy?

average number per Low-power field (LPF)

How are casts and crystals reported routinely

following examination of 10 field?

average number per 10 High-power fields (HPF)

How are RBCs and WBCs reported routinely?

1. Epithelial cells

2. Crystals

3. other elements

What are the formed elements frequently reported

in semiquantitative terms? (3)

- rare

- few

- moderate

-1+

-2+

etc.

Examples of SEMIQUANTITATIVE TERMS

RECHECK

for technical and clerical errors

What should be done in specimen results that

DO NOT CORRELATE with its physical and chemical findings?

1. AMOUNT of formed elements or chemicals

2. AGE of specimen

What must be considered in evaluating the

"correlations" of microscopic elements?

PREVENT the possibility of interference and false results

Why do we need to consider the

"amount" of formed elements or chemicals

and the "age" of specimen in evaluating the

correlations of microscopic elements?

1. Turbidity

2. Red color

PHYSICAL CORRELATIONS

of Microscopic Element: RBC

1. Blood ( + )

2. Protein ( + )

CHEMICAL CORRELATIONS

of Microscopic Element: RBC

Turbidity

PHYSICAL CORRELATIONS

of Microscopic Element: WBCs

1. Protein ( + )

2. Nitrite ( + )

3. Leukocyte Esterase ( + )

CHEMICAL CORRELATIONS

of Microscopic Element: WBCs

✅ Provide results as soon as possible

[MULTIPLE CHOICE]

Macroscopic screening of urine is used to:

a. Provide results as soon as possible

b. Predict the type of urinary casts present

c. Increase cost-effectiveness of urinalysis

d. Decrease the need for polarized microscopy

none

CHEMICAL CORRELATIONS

of Microscopic Element: Epithelial cells

Turbidity

PHYSICAL CORRELATIONS

of Microscopic Element: Epithelial cells

Protein ( + )

CHEMICAL CORRELATIONS

of Microscopic Element: Casts

Turbidity

PHYSICAL CORRELATIONS

of Microscopic Element: Bacteria

1. INCREASED pH 🡩

2. Nitrite ( + )

3. Leukocytes ( + )

CHEMICAL CORRELATIONS

of Microscopic Element: Bacteria

none

PHYSICAL CORRELATIONS

of Microscopic Element: Casts

Addis Count

This is the "first procedure" to standardize the

quantitation (or counting) of formed elements in

urine microscopic analysis; used as hemocytometer

by STAINING as it changes the refractive index

of sediment elements under the Bright-field Microscopy

How do we INCREASE the OVERALL VISIBILITY

of sediment elements being examined?

1. Nuclei

2. Cytoplasm

3. Inclusions

What are the identifying characteristics

of cellular structure imparted by STAINING?

Sternheimer-Malbin stain

What is the most frequently used stain in urinalysis?

CRYSTAL VIOLET

and

SAFRANIN O'

Composition of Sternheimer-Malbin stain

(2)

1. Sedi-Stain

2. KOVA stain

Other Names

for Sternheimer-Malbin stain

1. Sternheimer-Malbin

2. Toluidine blue

3. 2% Acetic Acid

4. Lipid stains (Oil Red O' and Sudan III)

5. Gram stain

6. Hansel stain

7. Prussian blue stain

STAINS used

for Urinary Sediment Elements

(7)

DELINEATES the structure and contrasting colors

of the nucleus and cytoplasm

Mode of Action

of Sternheimer-Malbin Stain

IDENTIFIES

1. WBCs

2. Epithelial cells

3. Casts

Function of Sternheimer-Malbin Stain

ENHANCES the nuclear details

Mode of Action

of Toluidine Blue

DIFFERENTIATES

WBCs and Renal Tubular Epithelial (RTE) cells

Function of Toluidine Blue

LYSES RBCs and

ENHANCES Nuclei of WBCs

Mode of Action

of 2% Acetic Acid

DISTINGUISHES

RBCs from WBCs / Yeast / Oil droplets / Crystals

Function of 2% Acetic Acid

STAINS the triglycerides and neutral fats

into ORANGE-RED

Mode of Action

of Lipid Stains: Oil Red O' and Sudan III

IDENTIFIES

1. Free fat droplets

2. Lipid-containing cells

3. Casts

Function of Lipid Stains: Oil Red O' and Sudan III

DIFFERENTIATES the

gram ( + ) and gram ( - ) bacteria

Mode of Action

of Gram Stain

IDENTIFIES

Bacterial casts

Function of Gram Stain

STAINS the eosinophilic granules

with METHYLENE BLUE and EOSIN Y

Mode of Action

of Hansel Stain

IDENTIFIES

Urinary Eosinophils

Function of Hansel Stain

STAINS the structures containing iron

Mode of Action

of Prussian Blue Stain

IDENTIFIES

Yellow-Brown Granules of Hemosiderin

within the cells and casts

Function of Prussian Blue Stain