Chapter 7 Flashcards
3rd part of routine urinalysis-
microscopic examination of the urinary sediment
Identification of insoluble substances (formed elements)- (11)
-Red blood cells (RBCs)
-White blood cells (WBCs)
-Epithelial cells
-Casts
-Bacteria
-Yeast
-Parasites
-Mucus
-Spermatozoa
-Crystals
-Artifacts
Microscope analysis is subject to several procedural variations- (4)
-The methods by which the sediment is prepared
-The volume of sediment actually examined
-The methods and equipment used to obtain visualization
-The manner in which the results are reported
Microscopic is performed based on-
physical & chemical results
Parameters considered significant for microscopic screenings include- (7)
-Color
-clarity
-blood
-protein
-nitrite
-leukocyte esterase
-possibly glucose
Special populations for microscopic examinations- (6)
-pregnant women
-pediatric
-geriatric
-diabetic
-immunocompromised
-renal patients
CLSI recommendations for microscopic examinations- (3)
-Requested by the physician
-Laboratory-specified population
-Any abnormal physical or chemical result
examine prepared specimens when- (2)
-fresh
-preserved
Formed elements in specimen examination- (4)
-RBCs
-WBCs
-casts disintegrate in dilute
-alkaline urine
refrigerating specimens precipitates-
crystals & can obscure other elements
Less contamination (epithelial cells) from a ________ specimen-
midstream clean-catch
Thoroughly mix specimen before-
decanting to the centrifuge tube
Standard amount of urine usually centrifuged-
10 – 15 mL
Quantities <12 mL of urine should be-
documented
Standardize speed and time of centrifugation should be-
consistent
ideal relative centrifuge force (RFC)-
5 minutes at RCF of 400
RCF corrects for variations in the diameter of-
centrifuge heads
Volume of sediment examined-
0.5 to 1.0 mL
Sediment must be resuspended via-
gentle agitation
Vigorous agitation of specimens must be-
avoided
Volume of sedimentation placed on microscopic slide should be-
consistent
Glass Slide method for volume of sediment examined- (3)
-recommended volume is 20 uL
-22x22 glass cover slip
-do not overflow cover slip (heavier elements/casts flow outside)
Microscopic analysis of urine has been improved substantially with-
commercial slide systems
CLSI recommends these systems together with-
standardization of all phases of the methodology
Commercial systems: KOVA- (5)
-Calibrated centrifuge tubes
-special slides to control volume
-decanting pipettes
-grids for better quantitation
Microscopic examination of sediment should be performed in a consistent manner & include-
observation of a minimum of 10 fields under low (10x) & 10 high (40x) fields
low power for examination of sediment- (2)
-casts, general composition
-Scan edges for casts with glass slide method
high power for examination of sediment-
identification of type
initial focusing for examination of sedimentation- (2)
-low power, reduced light
-Focus on epithelial cell, not artifacts that are in a different plane
adjustments used for examination of sedimentation-
fine adjustment continuously for best view
reporting the examination is consistent within-
the lab
Reporting the Examination casts-
average per lpf