AUBF: Microscopic Examination

Appearance of RBC in hypotonic urine

Colorless with membrane intact and regular; often lose their hemoglobin in a dilute urine with low specific gravity

Appearance of RBC in hypertonic urine

Lost their biconcave shape, the membrane becomes irregular, and the cells appear crenated; they appear like small spheres with spicules in a urine with high specific gravity

Dysmorphic: RBCs

Vary in size and shape, are often fragmented, or have cellular protrusions (burr cells or acanthrocytes)

These are cellular protrusions seen in dysmorphic RBCs

Burr Cells/ Acanthrocytes

Clinical Significance of increased RBCs

Seen with urinary tract infections (UTIs), trauma to the kidneys, or menstrual contamination

Clinical Significance of dysmorphic RBCs

Associated with glomerular membrane damage

UA Correlations of RBCs

Color - pink to bright red

Specific Gravity

Blood

Neutrophils

Granular and multinucleated; the majority of WBCs in the peripheral blood are neutrophils

What WBCs are agranular?

Lymphocytes and monocytes

Sparkling cytoplasm in the neutrophils associated with Brownian movement; they absorb water and swell

Glittercells

CS of Neutrophils

Associated with bacterial infection, cystitis, and inflammation

CS of Eosinophils

Associated with drug-induced interstitial nephritis

CS of Lymphocytes

Associated with renal transplant

CS of Monocytes

Associated with chronic inflammation

UA Correlations of WBCs

Clarity

Leukocyte Esterase

Nitrite

Large cells with abundant irregular cytoplasm and wrinkled borders; central nucleus the size of RBC; can be binucleated; tend to have multi ridge borders that tend to fold or curl

Epithelial cells

Variation of squamous epithelial cells; covered with Gardnerella coccobacillus, which gives the cell a granular appearance

Clue cell

CS of Epithelial Cells

Originate from the mucous membrane around the urethra

CS of Squamous Epithelial Cells

Associated with wear and tear from urethra or vaginal mucosa; seen more frequently in females

CS of Clue Cells

Pathological and indicative of vaginal infection caused by Gardnerella vaginalis

UA Correlations of Epithelial Cells

Clarity

High levels of Epithelial cells may indicate ___

Contamination from vaginal secretions or poor collection

These cells are smaller than Squamous Epithelial Cells

Transitional Epithelial Cells (Urothelial Cells)

What is the physical characteristic of Transitional Epithelial Cell

Can be spherical, pear-shaped, polyhedral, or caudate shaped with a centrally located nucleus; In elongated cells, the nucleus tends to be off-center; Cells contain a moderate amount of cytoplasm

CS of Urothelial Cells

Originate from mucosa of renal pelvis, ureter, and bladder; Appear in urine with infection, inflammation, renal stones, bladder cancer, and catheterization

UA Correlations of Urothelial Cells

Clarity

Blood (if malignancy is associated)

Clusters or sheets of urothelial cells are associated with ___

Catheterized Specimens

Urothelial cells tend to ___

Take on water and look like large round balloon

Originate from the proximal renal tubules, loop of Henle, distal convoluted renal tubules, and collecting ducts; vary in size and shape due to different origins

Renal Tubular Epithelial Cells

Proximal Tubular Cells are ___

Large in size and oblong in shape with grainy cytoplasm and eccentric nucleus

Distal Tubular Cells are ___

smaller and more round to oval with small, round eccentric nucleus

Collecting Duct Cells are ___

Polygonal or Cuboidal with large nucleus

CS of RTE Cells

Indicative of necrosis of the renal tubules, renal tubular damage, exposure to heavy metals, drug-induced toxicity, hemoglobin and myoglobin toxicity, ischemic events, and viral infections

UA Correlations of RTE Cells

Clarity

Color

Protein

Blood

Bilirubin (Hepatitis)

Leukocyte Esterase (Pyelonephritis)

Nitrite ( Pyelonephritis)

These are Renal Tubular Cells laden with fat; they are highly refractile, globular-shaped, and have an inconspicuous nucleus

Oval Fat Bodies

Oval fat bodies may demonstrate a Maltese Cross when using ___

Polarizing Microscopy

CS of Oval Fat Bodies

Associated with nephrotic syndrome, glomerular dysfunction, and renal tubular cell death

UA Correlations of Oval Fat Bodies

Clarity

Protein

Blood

Free Fat Droplets

Fatty Casts

Spherical Bacteria

Cocci

Rod-shaped Bacteria

Bacilli

CS of Bacteria

UTI

UA Correlations of Bacteria

Alkaline pH

Leukocyte Esterase

Nitrite

WBCs

WBCs in Clumps

These are colorless, small, refractile, round to oval structures that may be single, budding, or with pseudohyphae and branching

Yeast

CS of Yeast

Candida albicans found commonly in women, most often indicates vaginal secretion contamination or vaginal infection; can also be seen in diabetic or immunocompromised patients

UA Correlations of Yeast

Glucose

Increased WBCs

Leukocyte Esterase

Yeast does not dissolve when ___ is added

Acetic Acid

A trophozoite that is a pear-shaped flagellate with an underlying membrane that causes a rapid flitting motion; resembles WBC with tail-like flagella

Trichomonads

CS of Trichomonads

Trichomonas vaginalis is a sexually transmitted pathogen associated with vaginal or urethral inflammation; In males, it is asymptomatic (Pingpong disease)

UA Correlations of Trichomonads

Increased WBCs

Increased Epithelial Cells

WBC clumps

Leukocyte Esterase

This is a single or clumped, ribbon-like or thread-like structures that have irregular or serrated ends with low refractive index

Mucus

___ is required when using ___ microscopy

Subdued light - Bright-field

CS of Mucus

No CS, but can be abundant in the presence of inflammation or irritation

UA Correlation of Mucus

Clarity

Composed of uromodulin protein and appear colorless and transparent under low power (100×)

Hyaline Cast

Have Low refractive index similar to urine, making them difficult to see using bright-field microscopy

Hyaline Cast

CS of Hyaline Cast

Normal but increased with strenuous exercise, stress, fever, and dehydration; can be seen in patients with chronic renal disease and congestive heart failure

UA Correlation of Hyaline Cast

Protein

Blood

Physical Characteristic of RBC Cast

Contain RBCs in the protein matrix

Appear red to brown

CS of RBC Cast

Associated with damage to the glomerulus or glomerulonephritis, bleeding into the nephron, and lupus

UA Correlations of RBC Casts

Increased RBCs

Protein

Blood

This is a degenerated yellow-brown homogenous structure

Hemoglobin Cast

Physical Characteristics of WBC Cast

Contain WBCs with prominent nuclei in a cylindrical matrix

Have parallel sides and rounded edges

CS of WBC Cast

Can indicate renal inflammation, infection, acute pyelonephritis, or interstitial nephritis; The presence of WBC casts can distinguish pyelonephritis or upper UTI from cystitis or lower UTI

UA Correlations of WBC Cast

Protein

Leukocyte Esterase

Increased WBCs

Physical Characteristic of Bacterial Cast

Contain bacilli within the protein matrix

CS of Bacterial Cast

Diagnostic for pyelonephritis or upper UTI

UA Correlations of Bacterial Cast

WBCs

Bacteria

Protein

Leukocyte Esterase

Nitrite

Bacterial casts may be confused with Granular casts, hence, to confirm it utilizes ___

Gram stain

Physical Characteristics of Epithelial Cell Cast

Contain RTE Cells with large nuclei with high refractive index; degeneration of RTE Cells can make it smaller and round resembling WBCs

CS of Epithelial Cell Cast

Associated with acute tubular necrosis, advanced tubular destruction, and heavy metal or drug toxicity

UA Correlations of Epithelial Cell Cast

Protein

RTE Cells

Physical Characteristics of Granular Cast

Degeneration of cellular casts; granules begin large and are coarse and granular; As stasis continues, granules break down further and are called fine granular casts; Coarse granules are dark in color, and fine granules tend to be pale

CS of Granular Cast

Indicate urinary stasis, tubular disease, glomerulonephritis, pyelonephritis, or may be seen in stress or after exercise

UA Correlations of Granular Cast

Protein

RBCs

WBCs

Cellular Cast

Granular Casts are reported as ___

1. Coarse

2. Fine

3. Granular

Physical Characteristics of a Mixed Cell Cast

Contain multiple cellular constituents

CS of Mixed Cell Cast

Indicate renal disease and are usually seen with other cellular casts

UA Correlations of Mixed Cell Cast

Protein

Leukocyte Esterase

RBCSs

WBCs

RTE Cells

To positively identify a mixed cell cast, it must have ___

Free-floating cellular elements

Physical Characteristics of Fatty Cast

Highly refractile and may contain fat droplets and intact oval fat bodies

CS of Fatty Cast

Associated with nephrotic syndrome, acute tubular necrosis, diabetes mellitus, toxic tubular necrosis, and crushing injuries

UA correlations of Fatty Cast

Protein

Free Fat Droplets

Oval Fat Bodies

Maltese Cross Formations can be seen with ___ under polarization

Cholesterol

Physical Characteristics of Waxy Cast

Highly refractile with broken, jagged, or blunt ends with cracks on the margin of the matrix and can be colorless to gray in color

CS of Waxy Cast

Indicate urinary stasis, chronic renal failure, or end-stage renal disease

UA Correlations of Waxy Casts

Protein

Increased RBCs

Increased WBCs

Cellular Casts

Granular Casts

Waxy casts look like ___ sitting on top of the urine

Paraffin shavings

Waxy casts are often ___ in size due to renal stasis

Broad

Physical Characteristics of Broad Cast

Named due to its wide size

Formed due to the distension of the collecting tubules when they are formed

CS of Broad Cast

Extreme urinary stasis and renal failure

UA Correlations of Broad Cast

Protein

Increased RBCs

Increased WBCs

Granular Casts

Waxy Casts

Broad can be used to classify ___

Granular or Waxy Casts