Urinalysis- Microscopic Flashcards
Preservation
– Cells and casts begin to disintegrate in ___________
– Refrigeration for up to 48 hours (little loss of cells).
1 - 3 hrs . at room temp.
Abnormal Findings Per High Power Field (HPF) (400x)
– > 3 erythrocytes
– > 5 leukocytes
– > 2 renal tubular cells
– > 10 bacteria
Per Low Power Field (LPF) (200x)
– > 3 hyaline casts or > 1 granular cast
– > 10 squamous cells (indicative of contaminated specimen)
– Any other cast (RBCs, WBCs)
Abnormal finding AbPresence of:
– Fungal hyphae or yeast, parasite, viral inclusions
– Pathological crystals (leucine, tyrosine, cystine)
– Large number of uric acid or calcium oxalate crystals
Erythrocytes
“Dysmorphic” vs. “normal”
(> 10 per HPF)
Leukocytes
Neutrophils (glitter cells)
___________________
Eosinophils
Hansel test (special stain)
More than 1 per 3 HPF
Epithelial Cells
Renal tubular epithelial cells: _________________
Few are normal
From renal tubules (proximal, distal, collecting ducts)
Renal tubular epithelial cells must be enumerated using HPF
The presence of more than_____________ indicates tubular injury and specimens should be referred for cytologic urine testing.
Difficult to identify due to variability in appearance. Depending on the location.
Small, dense, eccentrically placed nucleus is a characteristic
2 RTE/HPF
Transitional Cells
Smaller than squamous epithelium
Increase in TC exhibiting abnormal morphology such as vacuoles and irregular nuclei may be indicative of malignancy or viral infection.
Transitional Cells
RTE that absorb lipids.
Usually seen in free floating fat droplets.
Usually stained by Sudan III or Oil Red O fat stains and examined in Polarized microscope.
Will produce Maltese cross appearance on Polarized lights
Oval Fat Body
Bacteria
Bacteriuria
More than 10 per HPF
Yeasts
Candidiasis
Most likely a contaminant but should correlate with clinical picture.
Viruses
CMV inclusions
Probable viral cystitis
Erythrocyte Casts:
Glomerular diseases
Leukocyte Casts:
Pyuria, glomerular disease
Granular casts
Nonspecific (Tamm-Horsfall protein)
Hyaline casts
Nonspecific (Tamm-Horsfall protein)
Waxy casts
Nonspecific
Fatty casts (oval fat body casts)
Nephrotic syndrome
____________ are the only urine sediment that are unique to the kidney.
Formed within the lumens of the distal convuluted tubules and collecting ducts.
Their shape is representative of the tubular lumen
Dissolves quickly in dilute alkaline urine.
Reported as the average number per 10 LPF
Casts are the only urine sediment that are unique to the kidney.
Formed within the lumens of the distal convuluted tubules and collecting ducts.
Their shape is representative of the tubular lumen
Dissolves quickly in dilute alkaline urine.
Reported as the average number per 10 LPF
Casts
Major constituent of a Cast is______________, a glycoprotein excreted by the RTE of the DCT and CD.
Tamm-Horsfall protein
Can be non pathologic or pathologic.
Granular Cast
When is the granular cast nonpathologic?
Non-pathologic if from the lysosomes excreted by RTE during normal metabolism. (extreme physical work)
When is the granular cast pathologic?
Pathologic if it represent disintegration of cellular casts and tubule cells or protein aggregates filtered by the glomerulus.
Frequently seen cast, consists almost entirely of Tamm Horsfall protein
Normal 0-2/LPF
Hyaline Cast
Hyalin cast can be seen in which diseases?
Can be seen in Acute Glomerulonephritis, pyelonephritis, CRD and CHF.
Represent extreme urine stasis, indicating CRF
Derived from the degenerating Hyaline and cellular cast.
Waxy Cast
Seen in conjunction with oval fat bodies and free fat droplets in disorders causing lipiduria.
Frequently associated with nephrotic syndrome, toxic tubular necrosis, DM, and crash injuries.
Fatty Cast
What are the crystals that can be found in urine?
Crystals
– Urate
o Ammonium biurate
o Uric acid
– Triple Phosphate
– Calcium Oxalate
– Amino Acids
o Leucine
o Cystine
o Tyrosine
– Sulfonamide
Normal crystal
Present in Acid/neutral pH
They are colorless, enveloped shape
Dumbbell shape (2nd photo)
Calcium Oxalate Crystals
Normal crystal
Alkaline pH
Colorless (coffin lids)
Triple Phosphate Crystals
Normal crystals
Most commonly seen as amorphous urates, uric acid, acid urates and sodium urates.
Appear reddish to brown and are the only normal crystals found in acidic urine that appear colored.
Urate cyrstals
Urate crystal
Abnormal crystal
Acidic/neutral urine
Fine colorless to yellow
needles that frequently form clumps
or rosettes
Associated with liver
disorders
Tyrosine Crystals
Tyrosine cystal
Abnormal crystal
Acid urine
Colorless, hexagonal
plates may be thick or thin.
Associated with
hereditary cystinuria
Cystine Crystals
cystine crystal
Normal Crystal
Alkaline Urine
Yellow brown crystals
(“thorny apple”)
Ammonium Biurate Crystals
Ammonium Biurate
Abnormal crystal
Acid urine
Colorless notched plates
Disorders producing lipiduria like nephrotic syndrome.
Cholesterol Crystals
Cholesterol crystal
Uses and Limitations of Urine Protein Detection Significance
– Proteinuria and the nephrotic syndrome.
Limitations
– Interference: highly alkaline urine.
– Much more sensitive to albumin than other proteins (e.g. immunoglobulin light chains).
Other Tests For Urine Protein determination
– Sulfosalicylic acid (SSA) turbidity test.
– Urine protein electrophoresis (UPEP)
– Bence Jones protein
Alkaline urine overrides the acid buffer system, producing a rise in pH and a color change unrelated to protein concentration.
____________ is a bile pigment that results from the degradation of hemoglobin.
Produced in the intestine from the reduction of bilirubin by intestinal bacteria.
Urobilinogen:
for porphobilinogen
Watson-Schwartz and Hoesch screening test f
Uses and Limitations of Urobilinogen Detection Significance
\
– High: increased hepatic processing of bilirubin
– Low: bile obstruction
Limitations Urobilinogen
– Interference: prolonged exposure of specimen to oxygen (urobilinogen —> urobilin)
– Cannot detect low levels of urobilinogen
Uses and Limitations of Nitrite Detection Significance
– Gram negative bacteriuria
Nitrite
Limitations in Nitrite Determination
Limitations
– Interference: bacterial overgrowth
– Only able to detect bacteria that reduce nitrate to nitrite
Other Tests
– Correlate with leukocyte esterase and
– Urine microscopic examination (bacteria)
Ability of certain bacteria to reduce nitrate, which is a normal constituent of the urine, to nitrite.
It is detected by________________
Test is standardized to correspond with a quantitative bacterial culture criterion of 100,000 organisms per milliliter.
Greiss reaction.
The _____________ detects the presence of esterase in the granulocytic white blood cells. Neutrophils are most frequently associated with bacterial infection.
Esterases are also present in Trichomonas and histiocytes.
Action of LE to catalyze the hydrolysis of an acid ester to produce an aromatic compound and acid.
It will then combine with diazonium salt to produce a purple azodye.
Leukocyte Esterase
Uses and Limitations of Leukocyte Esterase Detection Significance
– Pyuria
– Acute inflammation
– Renal calculus
Note : Limitations
– Interference: oxidizing agents, menstrual contamination
Other Tests
– Urine microscopic examination (WBCs and bacteria)
– Urine culture
