Urine Sediments: Cells And Crystals Flashcards
Proper magnification for enumerating casts
Low
What is the recommended volume, centrifugation time and speed for microscopic evaluation
Volume: 10-15 mL (12 preferred)
Time: 5 minutes
Speed: 400-450 g
Proper magnification for enumerating mucus
Low
Proper magnification for enumerating crystals, cells and yeast?
High power
How do RBCs act in hyper/hypotonic urine
Hyper: crenated
Hypo: swelled, lyced, or ghost cells
How do WBCs act in hyper/hypotonic solutions
Hyper: shrink but not crenate
Hypo: enlarge and may lyse
How do you differentiate RBCs from yeast?
Yeast varies in size, not biconcave, budding
How do you differentiate RBCs from air bubbles/oil droplets
They are refractile, variation in size, uniformity in appearance
How do you differentiate RBCs from calcium oxalate crystals
enveloped shaped
Significance of WBCs in the urine
Pyuria is seen in infections and autoimmune conditions (infections, lupus, TB etc)
- Pyuria, WBC casts, cellular casts, or granular casts, usually high protein = upper UTI
- Pyuria without casts and low protein (to none) = lower UTI
Significance of RBCs in the urine
Hematuria indicates damage to the kidney or urinary tract
- RBCs/RBC Casts/Protein = renal origin either glomerular or tubular
- RBCs/no casts/no protein = bleeding “below” the kidney or contamination
Squamous epithelial Cells
- appearance
Flat with irregular shapes, central round nucleus
Squamous epithelial Cells
- location
vaginal contamination in urines from women
Squamous epithelial Cells
- clinical Significance
rare diagnostic significance
Transitional Epithelial Cells
- appearance
Round, pear shaped, or tail like projection, central round nucleus
Transitional Epithelial Cells
- location
originate in renal pelvis, calyces, ureter, urinary bladder and upper part of urethra in males
Transitional Epithelial Cells
- clinical significance
Increased numbers: UTI, Viral illness, Catheterization, malignancy (transitional cell carcinoma)
Renal Tubular Epithelial Cells
- appearance
Polyhedral-flat, cuboidal, columnar, eccentric nucleus (BIG nucleus)
Renal Tubular Epithelial Cells
- location
originate in lining of the renal tubules and collecting ducts
Renal Tubular Epithelial Cells
- clinical significance
MOST SIGNIFICANT epi cell
- Pathologic: pyelonephritis, kidney damage from meds or toxins, tubular necrosis, renal transplant rejection, viral infections (HEP B)
Origin of an oval fat body
Renal tubular epic cell with absorbed lipids
Contrast cholesterol and neutral fats with respect to stains and birefringence
Cholesterol is birefringent (use polarizing microscope)
Neutral fats are not birefringent but can be stained with Sudan Red or Oil Red O
Difference between oval fat bodies, air bubbles and starch granules
Starches have maltese cross pattern under polarized light
Oils are refractive, vary in size and uniformity in appearance
Significance of spermatozoa in urine
Males: rencent ejaculation or nocturnal emission
Females: vaginal contamination
Normal Acidic Crystals
Uric Acid Amorphous Urates Calcium Oxalate Hippuric Acid Sodium Urate
Abnormal Acidic Crystals
Tyrosine Leucine Bilirubin Cystine Cholesterol Sulfonamide Radiographic Dye
Alkaline Crystals (no abnormal crystals in alkaline urine)
Amorphous phosphates Triple phosphates Calcium Carbonates Calcium Phosphates Ammonium Biurates
Presence of WBCs in the urine
pyruia
Presence of RBCs in the urine
hematuria
Neutrophils that have swelled in a hypotonic solution and their refractile cytoplasmic granules move by Brownian movement and “glitter”
glitter cells
Fat in the urine
lipiduria
