420 Casts / Crystals /Other

Urinalysis Microscopics

Significance of RBCs in urine

Glomerular membrane damage

Vascular Injury

Vaginal Contamination

Ghost Cells happen when

RBCs absorbing water in diluted urine

Crenated RBCs happen when

loss of water in concentrated urine

How does acidic urine affect RBCs/WBCs? 

Preservation of morphology

How does alkaline urine affect WBC/RBCs?

May lyse cells

what are most of these cells

RBC

Glitter cells

WBCs that have been in diluted or alkaline urine and lyse, losing nuclear detail.

Significance of WBCs in urine

Inflammation, infection

Glomerular or capillary trauma

what dis

WBC

Large and flat cell with a small single nucleus

Squamous epithelial

what dese

Squamous Epithelial Cell

Clue cells are:

Bacteria adhering to squamous epithelial cells, which extend beyond the cell border

Round, central nuclear cells which line the ureters, bladder, and upper urethra

Transitional Epithelial cells

Why might we see transitional epithelial cells in the urine?

Normal sloughing, catheterization, malignancy, or infection

Round, larger than WBC cells with an eccentric nucleus that line the renal tubules

RTEs

Significance of RTEs in the urine

Exposure to toxins, viral infections, pyelonephritis, or transplant rejection. 

what these

RTE

identify

Transitional Epithelial

What is an oval fat body?

RTE with adsorbed lipids

How do we confirm oval fat bodies?

Polarized Microscopy or Stains for Fat (Sudan / Oil Red)

Significance of oval fat bodies

Nephrotic syndrome

How are casts formed? What protein

Precipitation of Tamm-Horsfall mucoprotein (uromodulin) That cells/proteins in the renal tubules can become conglutinated with.

What conditions favor cast formation?

Slow flow, concentrated, and acidic urine.

what

Hyaline Cast

Hyaline significance

Strenuous exercise, stress, dehydration, glomerulonephritis, pyelonephritis, chronic renal disease

this is:

RBC cast

Significance of RBC cast

Bleeding in the nephron

(acute glomerulonephritis, lupus nephritis, pyelonephritis, strenuous exercise) verify with positive blood on reagent strip + free standing RBCs on slide

what this

WBC cast

Significance of WBC casts

Pyelonephritis, Lupus nephritis, Glomerulonephritis

what hapepend here

WBC clump

what

Epithelial cell cast

What do epithelial cell casts suggest?

Excessive desquamation (glomerulonephritis, pyelonephritis, renal vascular disease, exposure to toxin, viral infections, and allograft rejection) 

?

Granular Cast

Significance of Granular Casts

Glomerulonephritis

Pyelonephritis

Strenuous exercise

this is what

Waxy cast

What significance do Waxy casts have?

Extreme stasis of urine flow

Chronic Renal Failure

?

Fatty cast

Significance of fatty casts

Chronic renal disease, nephrotic syndrome

How do we confirm fatty casts?

Polarized microscopy or fat stains. 

Amorphous Cystals in acidic and alkaline urine

Acidic = urates

Alkaline = phosphates

“Coffin Lids” AKA

Triple Phosphate (alkaline)

“Thorny Apples”

AKA

Ammonium biurate (alkaline)

This is:

Calcium phosphate (alkaline)

Alkaline normal crystals

Triple Phosphate

Ammonium Biurate

Calcium phosphate

Normal Acidic Crystals

Calcium oxalate and uric acid

the envelope ones aka

Calcium oxalate

What causes calcium oxalate?

Foods high in oxalic acid, antifreeze posioning, main culprit of renal calculi

and these r:

Uric Acid

3 forms of calcium oxalate

envelope, oval, dumbbell

dis is:

Bilirubin

Liver disease

this one is tricky

Cholesterol

Nephrotic Syndrome (may see fatty casts)

this one might be my favorite

Leucine

Liver disease

ts Is:

Tyrosine

Liver disease

this one might also be a top 3

Cystine

Cystinuria/Cystinosis

emojis pointing at

Sulfonamide

I do not like this one

Ampicillin

tricky pt 2. 

Renografin

How to distinguish renografin from cholesterol crystals?

Look at specific gravity and patient history

wash urself or u will get:

Yeast

Diabetics, immunocompromised, infections

wrap it up or you will get:

Trichomona

Sexually transmitted parasite

Usual kind of bacteria found in urine

gram negative rods

How to tell apart yeast vs RBC?

Look for budding pattern

Can lyse RBCs with acetic acid

Why might we question a UTI diagnosis if bacteria are visible on the microscopic exam?

If there’s not WBCs, it may be due to contamination or poor preservation.