Microscopic Examination of Urine Flashcards
What does the abbreviation CLSI mean
Clinical and Laboratory Standards Institute
The CLSI recommends that microscopic analysis of the urine be performed when __ and __.
- Requested by a physician
2. Abnormal physical/chemical result is obtained
Casts are reported as the average number per _ following an examination of _ fields.
LPF; 10
RBCs and WBCs, are reported as the average number per _ following an examination of _ fields.
HPF; 10
Point of a reference plane
Presence of epithelial cells
Reported semiquantitatively
Epithelial cells, crystals, and other elements
This procedure utilizes a hemocytometer to count the number of RBCs, WBCs, casts, and epithelial cells present in a 12-hr specimen
Addis count
Most frequently used stain in urinalysis which consists of crystal violet and safranin O
Sternheimer-Malbin Stain
This stain delineates the structure and contrasting colors of the nucleus and cytoplasm
Sternheimer-Malbin Stain
This stain distinguishes RBCs from WBCs, yeast, crystals, and oil droplets
2% Acetic acid
This stain identifies urinary eosinophils
Hansel Stain
These stains stain triglycerides and neutral fats orange-red
Oil Red O and Sudan III
Lipid stains such as Oil Red O and Sudan III do not stain _
Cholesterol
* but cholesterol is capable of polarization
This stain identifies bacterial casts by differentiating gram-positive and gram-negative bacteria
Gram stain
This stain differentiates WBCs and RTE cells by enhancing nuclear detail
Toluidine blue
Gram-positive stain color; Gram-negative stain color
Gram (+)= blue
Gram (-)=red
What must be prepared when gram staining the urine sediment
Heat-fixed urine sediment
Hansel stain consists of _ and _
methylene blue and eosin Y
Another stain that can also be used for the detection of eosinophils
Wright’s stain
Prussian blue stain confirms the presence of _
Hemosiderin
Crenated RBCs signify a _ urine
Hypersthenuric
Product of hypostenuric urine
Ghost cells
* Hyposthenuric (dilute): Cells absorb water, swells, and lyse rapidly releasing hemoglobin. Only the membrane is left.
Normal characteristic of RBCs in urine
Smooth, non-nucleated, biconcave disk at 7mm
Morphology of urinary RBCs may aid in the determination of _ .
Site of renal bleeding
Dysmorphic RBCs are associated primarily with _
Glomerular bleeding
* Dysmorphic na kasi galing pa sa glomerulous kaya dumaan, daan pa sa buong urinary tract. *RBCs are fragile.
Characteristic of dysmorphic RBCs associated with glomerular bleeding
Acanthocyte with multiple portrusions
Diameter of WBCs
12 mm
Predominant WBC found in urine
Neutrophils
Neutrophils lyse rapidly in concentrated/dilute, acidic/alkaline urine, and begin to lose nuclear detail
dilute alkaline
Product of neutrophils exposed to hypotonic urine
Glitter cells
* Due to the Brownian movement of the granules because the cell has absorbed water
Color of glitter cells when stained with Sternheimer-Malbin
Light blue
Urine sediment primarily found in drug-induced interstitial nephritis
Eosinophils
The percentage of eosinophils in _ cells is determined.
100-500
* 1% Eo = clinically significant
Recommended urine sediment when using a conventional glass slide method
20 uL (0.02 mL) covered by 22x22 mm glass coverslip
Frequently used volume for sediment preparation
0.5 and 1mL
Distinguishing color of stained T. vaginalis in urine
Light blue-green
Stain of motile vs non-motile bacteria
Motile: Do not stain; non-motile: Purple
Microscope needed in order to distinguish cholesterol
Polarizing microscope
Specimen for the detection of eosinophil urine sediment using Hansel stain
Centrifuged / cytocentrifuged urine
Microscope needed to detect treponema pallidum
Darkfield microscopy
The microscope that produces a three-dimensional microscopy image
Interference microscope
Enhances visualization of low refractive indices such as hyaline casts, mixed cellular casts, mucous threads and Trichomonas
Phase-contrast microscopy
Estimate report for a macroscopic hematuria
> 100 RBCs/hpf
Color of Glitter cells when stained with Sternheimer-Malbin stain
Light blue
The presence of urinary eosinophils is primarily associated with _
Drug-induced interstitial nephritis
The largest cell found in a urine sediment
Epithelial cells
These cells are an indication of vaginal infection by the bacterium Gardenerellla vaginallis
Clue cells
*Clue cells are epithelial cells w/ attached G. vaginiallis coccobacillus
Difference of a transitional epithelial cell from RTE cells
Transitional epithelial cells: central nucleus
RTE cells: eccentric nucleus
Largest RTE cell
RTE cells from the PCT (rectangular shape)
- DCT=round/oval
- Collecting Duct= Cuboid
The presence of _RTE cells /HPF is indicative of tubular injury
> 2 RTE cells/hpf
Hemoglobin present in the filtrate is absorbed by the RTE cells and converted to _
Hemosiderin
Lipid containing RTE cells
Oval fat bodies
Lipiduria is most commonly associated with the damage to the glomerulus caused by _
Nephrotic syndrome
Represents injured cells in which the endoplasmic reticulum has dilated prior to cell death
Bubble cells
Unacceptable specimen pH
pH 8
True UTI
Bacteria accompanied by WBCs
Most frequently assoc. bacteria with UTI
Enterobacteriaceae (gram - rods)
- Staphylococcus and Enterococcus are also capable of producing UTI
Primary yeast seen in diabetic patients, immunocompromised patients, and women with vaginal moniliasis
Candida albicans
True yeast infection
yeast accompanied by WBCs
The most frequent parasite encountered in the urine
T. vaginalis
Movement of T. vaginalis
Rapid darting movement
Parasites seen in urine
- T. vaginalis
- Schistosoma haematobium (bladder parasite)
- Enterobius vermicularis
Most common fecal contaminant in the urine
E. vermicularis
Major constituent of mucous
uromodulin
The shape is representative of the tubular lumen
Casts
Major constituent of casts
Uromodulin
- Uromodulin is found in both normal and abnormal urine
Term to casts when they are formed at the junction of the ascending loop of Henle and the distal convoluted tubule
Cylindroids
Color of casts when stained with Sterheimer-Malbin
Pink
RBC casts are primarily associated with
Glomerulonephritis
Fats do NOT stain with _
Sternheimer-Malbin stains
The shape of renal tubular cells in
PCT:
DCT:
Collecting Duct:
The shape of renal tubular cells in
PCT: Rectangular (biggest)
DCT: Round or oval
Collecting Duct: Cuboidal
Most clinically significant of the epithelial cells
Renal Tubular Epithelial cells
Characteristic of cholesterol under the polarizing microscope
Maltese cross
True / False
Urine is not toxic to spermatozoa, therefore they may exhibit motility
False. Urine is toxic to spermatozoa
WBC casts are most associated with _
Pyelonephritis
Two types of granular casts
Fine and coarse granular casts
Waxy casts are indicative of
CHRONIC RENAL FAILURE
Casts that are indicative of chronic renal failure
WAXY CAST
Color of waxy casts when stained with Supravital stain
Homogenous pink ** jagged ends
Often referred to as the “Renal Failure Cast”
BROAD CAST
Broad casts are otherwise known as
RENAL FAILURE CASTS
Most commonly seen broad casts
Granular and Waxy broad casts
Broad casts are a mold of the _ tubule
Distal convoluted tubule ** Broad casts indicate widening of the tubular walls
Reporting of crystals
Rare, few, moderate or many per hpf
Factors involved in crystal formation
- pH
- Solute concentration
- Temperature
- Slower crystallization produces larger crystals
T/F:
Solutes precipitate more readily at low temperatures, therefore the majority of crystal formation takes place in specimens that have remained at room temperature/ has been refrigerated
True
The crystal which precipitates in acidic, neutral, and alkaline urine
Calcium Oxalate
All abnormal crystals are found in _ urine
Acidic
T/F
Polarization may be used for identifying crytals
FALSE. Polarization is constant for all crystals. pH is used to identify the crystal
Crystals that are frequently seen in refrigerated specimens
Amorphous Urates
*uR(efrigerated)ates
Amorphous urates may be dissolved if the specimen is _
If the specimen is warmed (37C)
Amorphous phosphates cannot be dissolved through warming, and require _ in order to dissolve
Acetic acid
*RBCs will also be destroyed
Normal crystals that are seen in acidic urine:
- Amorphous urates
- Uric acid
- Acid urates
- Sodium urates
Amorphous urates are seen in acidic urine with a pH greater than _
- 5 pH
* Uric acid crystals appear when the pH is lower
Disease associated with increased production of uric acid
Lesch-Nyhan syndrome
Most common form of calcium oxalate
Dihydrate form (octahedral envelope / 2 pyramids joined at their bases)
Shape of monohydrate calcium oxalate
Dumbell shape
Majority of renal calculi care composed of _
Calcium oxalate
High ascorbic acid levels in the body may result to what crystal in urine?
Calcium oxalate
because oxalic acid is the end product of acid metabolism
_ is seen in cases of ethylene glycol (antifreeze) poisoning
Monohydrate form of calcium oxalate
Phosphates represent the majority of the crystals seen in _ urine
Alkaline urine
Difference of amorphous urates from amorphous phosphates:
Urates: Acidic, yellow-brown in color
Phosphates: Alkaline, white in color
Most commonly seen crystal in ALKALINE urine
Triple phosphate (ammonium magnesium phosphate)
Shape of triple phosphate
Coffin-lid / Prism shape
- as they disintegrate, they may produce a feathery appearance
Calcium phosphate crystals dissolve in _
Dilute acetic acid
*Sulfonamides do not dissolve in dilute acetic acid
The crystal that forms gas after the addition of acetic acid
Calcium carbonate crystals
Characteristic of Ammonium Biurtate crystals
“Thorny apples” / Spicule covered spheres
Ammonium biurate crystals dissolve at _ and convert to _ when glacial acetic acid is added
dissolve at 60C
convert to uric acid crystals
Most commonly encountered crystal in old specimens
Ammonium biurate
* Associated with the presence of ammonia produced by urea-splitting bacteria
Positive confirmation of cystine crystals is made using _ _
Cyanide nitroprusside test
Characteristic of cystine crystals in urine
Colorless, thick/thin hexagonal plates (benzene)
Characteristic of cholesterol crystals in urine
Colorless, rectangular plate with a notched in 1/more corners
Crystals associated with liver disorder
TaLagang Bugbog na Liver (TLB)
Tyrosine, Leucine and Bilirubin
Crystal confused with Cholesterol crystals
Radiographic dye
*to differentiate=check patient history and compare urinalysis results.
Colorless-yellow needles that frequently form clumps or rosettes
Tyrosine crystals
Yellow-brown spheres that demonstrate concentric circles and radial striations
Leucine crystals
Clumped needles/granules with yellow color of bilirubin
Bilirubin crystals
Common crystals found in patients being treated with UTI
Sulfonamide crystals
*Inadequate hydration is the primary cause of sulfonamide crystals
Result of precipitation of antibiotics
Ampicillin crystals
