Clinical Microscopy Flashcards
Shorter urethra –> higher chance of UTI
Females (3-4cm)
Males (20cm)
1 kidney = _____ number of nephrons
1M-1.5M
Part of the nephron that acts as a sieve
Glomerulus
Glomerulus allows the filtration of substances with molecular weight of
Less than 70000 daltons
Major site of renal absorption
Proximal Convoluted Tubule
Part of the nephron impermeable to water
Ascending loop of Henle
Hormone that regulates water reabsorption in CT and DCT
Anti-diuretic hormone / Vasopressin
Endocrine gland that acts as storage of hormones produced by other glands
Post Pituitary Gland
Characterized by deficiency of Anti-diuretic hormone
D. insipidus
Major mineralocorticoid
Aldosterone
Function of aldosterone
Regulate reabsorption of sodium ions
First to be affected by renal disease
Tubular reabsorption
Gold standard for clearance test
Inulin
Preferred test/s for tubular reabsorption
Specific gravity and osmolarity test
Active/Passive Transport
- Glucose
Active transport
Active/Passive Transport
- Amino acid
Active Transport
Active/Passive Transport
- Water
Passive transport
Major organic organic component of urine
Urea
Major inorganic organic component of urine
Chloride
Principal salt in urine
NaCl
Method of collection for anaerobic culture
Suprapubic aspiration
Influenced by both number and density of particles in the solution
Specific gravity
Influenced by only the number of particles in solution
Osmolarity
Causes freezing point depression
High osmolarity
Drop in the freezing point with 1Osm/kg water
1.86C
Urine collection method for prostatic infection
Glass Technique / Three-glass technique
Tube collection for three-glass technique
1: first portion of voided urine
2: middle portion = midstream clean catch
3: urine after prostate massage
Volume of urine for drug specimen collection
30-45mL in a 60mL container
Optimal temperature for drug specimen
32.5-37.7C
Type of urine specimen for routine and qualitative analysis
Occasional/single/random
Type of urine specimen for quantitative analysis
Timed
Type of urine specimen for urobilinogen
Timed - afternoon specimen (2-4PM)
Type of urine specimen for nitrite determination
Timed - 4hrs
Ideal specimen for routine urinalysis
First morning clean catch
Type of urine specimen for pregnancy test
First morning
Type of urine for glucose determination
Fasting/second morning
Changes in unpreserved urine : color
Modified or darkened due to red-ox metabolism
Changes in unpreserved urine : clarity
Decreased due to pot of urates and amorphous phosphates and increase in bacterial count
Changes in unpreserved urine : odor
Increased due to ammonia build-up
Changes in unpreserved urine : pH
Increased due to ammonia build-up
Changes in unpreserved urine : glucose
Decreased due to glycolysis
Changes in unpreserved urine : ketones
Decreased
Changes in unpreserved urine : bilirubin
Decreased because it is light sensitive
Changes in unpreserved urine : urobilinogen
Decreased due to transition to oxidation to urobilin
Changes in unpreserved urine : nitrite
Increased due to bacteria multiplication
Changes in unpreserved urine : RBC/WBC
Decreased due to disintegration at high pH
Changes in unpreserved urine : bacteria
Increased
Most common physical method of preservation
Refrigeration
Chemical preservative for urine culture
Boric acid
Chemical preservative for addis count
Formalin
Chemical preservative for urine glucose
Sodium fluoride or benzoic acid
Disadvantage of refrigeration as a method of preservation
Precipitates amorphous urates and phosphates
Preservation method/technique that does not interfere with chemical tests
Refrigeration
Preservative that preserves protein and formed elements well and does not interfere with routine analyses other than pH
Boric Acid
Preservative that can act as a reducing agent,thus can interfere with different chemical tests
Formalin
Volume of urine specimen for urinalysis
10-15mL in a 50mL capacity container
Average of 12mL
Normal volume range of 24hour urine
600-2000mL
An increase in daily urine volume of greater than 2.5L/day in adults
Polyuria
Cases in which polyuria occurs
- increased fluid intake
- diuretic medication and drinks
- nervousness
- Diabetes mellitus
- Diabetes insipidus
A decreased in urine output of less than 400mL/day in adults
Oliguria
Failure of the kidneys to produce urine due to complete obstruction
Anuria
> 500mL, with specific gravity less than 1.018, urine output at night
Nocturia
- seen in pregnancy
Increase in fluid intake causes pale urine and a [decrease/increase] of specific gravity
Decrease
Differentiate diabetes mellitus from diabetes insipidus
Both cause an increase in volume but the specific gravity of the urine in DM is increased compared to the decrease in DI
Roughly indicates degree of hydration and should correlate with the urine specific gravity
Urine color
Specific term for yellow pigment in urine
Urochrome
Major pigment in urine
Urochrome
Specific term for green pigment in urine
Uroerythrin
Uroerythrin attaches to ______, producing a pink color t the sediment
Uroerythrin attaches to urates —-> amorphous urates
Specific term for urine pigment that is dark yellow or orange in color
Urobilin
A urine pigment that the production is dependent on the body’s metabolic state
Urochrome
Urine pigment that is an oxidation product of of urobilinogen, and imparts an orange-brown color to standing urine
Urobilin
White foam in dark yellow to orange urine
- concentrated urine
- presence of proteins
Color of urine in diabetes mellitus and diabetes insipidus
Pale yellow
Color of urine in the presence of bilirubin
Dark yellow with yellow foam
Treatment for UTI that renders the urine viscous and with yellow foam
Pyridium
Yellow-green color of urine
Bilirubin oxidized to biliverdin
Color of urine in Pseudomonas infection
Green
Color of urine the presence of indican
Blue-green
Most common abnormal urine color
Red
Color of the urine in the presence of RBC
Cloudy red
Color of the urine in the presence of Hemoglobin
Clear red
Color of the urine in the presence of Myoglobin
Clear red
Color of the urine in the presence of porphyrin
Red/purplish)
(lead porphyria may render colorless/normal urine
Color of the urine in lead porphyria
Normal (pale yellow)
What is deficient in Alkaptonuria
Homogentisic acid oxidase deficiency
Color of the urine in the presence of RBCs oxidized as metHb
Brown-Black
Color of the urine in the presence of mepacrime (antimalaria)
Yellow
Color of the urine in the presence of rifampin
Bright orange-red
Viewing of urine
Against white background using adequate light source
Describe clear urine
Transparents; no visible particulates
Describe hazy urine
Few particulates, print easity seen through urine
Describe cloudy urine
Many particulates, print is blurred through urine
Describe turbid urine
Print cannot be seen through urine
Describe milky urine
May precipitate or clot
Pathologic causes of turbidity
RBCs WBCs Bacteria Yeast Non-squamous epithelial cells Abnormal crystals Lymph fluid Lipids
Non-pathologic causes of turbidiy
Squamous cells Mucus Amorphous crystals Semen and/or spermatozoa Decal contamination Radiographic contrast media Talcum powder Vaginal cream
Substances correlated to acidic urine
Amorphous urates
Radiographic contrast media
Substances correlated to alkaline urine
Amorphous phosphates
Carbonates
Substances found in urine that are soluble in heat
Amorphous urates
Uric acid crystals
Substances found in urine that are soluble in dilute acetic acid
RBCs
Amorphous phosphates
Carbonates
Substances found in urine that are insoluble in dilute acetic acid
WBCs
Bacteria
Yeast
Spermatozoa
Substances found in urine that are soluble in ether
Lipids
Lymphatic fluid
Chyle
Color of urine with bilirubin-biliverdin
Yellow green with yellow foam OR beer-brown with yellow foam
Color of urine with fuscin (food with additive/food coloring)
Red
Color of urine with bilifuscin (unstable hemoglobin)
Red-brown
Color of urine with methemoglobin
Brown-black rendering an acidic pH
Specific gravity of isothenuria
1.010 (glomerular filtrate)
Determination of specific gravity that measures total solutes of the urine and its refractive indices
Refractometry
Refractometry is compensated to ________ and needs corrections for __________
Compensated to TEMPERATURE (15-38C) and needs corrections for GLUCOSE AND PROTEIN
Compensation for the specific gravity from refractometry
1g/dL glucose = - 0.004
1g/dL protein = - 0.003
Substances for the calibration of refractometry
Distilled water (1.000)
5% NaCl (1.022 +/- 0.001)
9% sucrose (1.034+/- 0.001)
Refractometry reading is [lower/higher] than urometer by [value]
Lower by 0.002
Urometer needs corrections for __________
TEMPERATURE
+/- 0.001 for every 3C the specimen is above/below the calibration temperature (20C) respectively
Principle of the reagent strip test for specific gravity of urine
pKa change of a polyelectrolyte (dissociation constant)
Principle of the Harmonic oscillation densitometry
Frequency of sound waves entering a solution will change in proportion to the density of the solution
Normal pH of (random) sample urine
4/5 - 5.0
Conditions that cause acidic urine
Emphysema Diabetes mellitus Starvation Dehydration Acid-producing bacteria High protein diet Cranberry juice
Conditions that cause alkaline urine
Vomiting Renal tubular acidoses Vegetarian diet Old specimen Urease-profucing bacteria
Odor of urine with Proteus
Urease-producing bacteria –> ammoniacal
Odor of urine with DM
Fruity/sweet due to metabolism of ketones
Rancid butter odor of urine
Due to tyrosinemia
Rotting fish odor of urine
Trimethylaminouria
Sweaty feet odor of urine
Isovoleric acidemia
Mousy odor of urine
PKU
Cabbage odor of urine
Methionine malabsorption
Bleach odor of urine
Contamination
Sulfur odor of urine
Cystine disease
Major serum protein found in urine
Albumin
Normal protein levels of urine
<10mg/dL or 100 mg/24 hours
Conditions leading to pre-renal proteinuria
- Intravascular hemolysis (Hb)
- Muscle injury (Myoglobin)
- Sever infection and inflammation (APRs)
- Multiple myeloma (proliferation of Igs by plasma cells)
Glomerular disorders leading to renal proteinuria
- Diabetic nephropathy (not detected by routine reagent strip)
- Orthostatic or postural proteinuria (due to pressure on renal veins)
Tubular disorders leading to renal proteinuria
- Fanconi’s dis
- Toxic agents/heavy metals
- Severe viral infections
Conditions leading to post-renal proteinuria
Lower UTI/inflammations
Tests for proteinuria
- Protein Reagent Strip (+ blue-green)
- Sulfosalicyclic Acid Precipitation Test (clumps)
Renal threshold for glucose
160-180mg/dL
Hyperglycemia associated glucosuria
* Glucose is high in BOTH blood and urine* DM Pancreatic cancer Cushing's syndrome Acromegaly Hyperthyroidism Stress Gestational diabetes
Renal associated glucosuria
- NORMAL blood glucose; HIGH urine glucose*
Fanconi’s syndrome
Advanced renal disease
Pregnancy
Tests for glucosuria
- Reagent Strip (+ blue-green)
- Copper Reduction Test (+ brick red)
- Glucose oxidase and clinitest reactions
Significance of ketones in the urine
- inability to metabolize glucose (DM)
- increased loss of carbs (vomiting)
- inadequate intake of carbs (starvation and malabsorption)
Hematuria
RBC in urine –> cloudy red appearance
Hemoglobinuria
Intravascular hemolysis –> clear red appearance
Myoglobinua
Rhabdomyolysis –> muscle destruction –> clear red appearace
Hemoglobinuria vs Myoglobinuria : Plasma examination
Hb: Pink/Red (high CK and aldolase)
Myoglobin: yellow (low haptoglobin)
Hemoglobinuria vs Myoglobinuria : Blondheim’s test (ammonium sulfate)
Hb: Clear supernatant; neg. reagent strip
Myoglobin: Red supernant; pos. reagent strip
Significance of bilirubin (conjugated) in urine
Early indication of liver disease
Micral Test:
- Test for
- Principle
Test for proteinuria (glomerular - renal)
Principle: Enzyme immunoassay
Sulfosalicyclic acid precipitation test
- Test for
- Principle
Test for general proteinuria
Principle: Cold precipitation (reacts equally to all forms of protein)
Principle for the reagent strip for proteinuria
Protein error of ndicators
Principle for the reagent strip for glucosuria
Double sequential enzyme reaction
+ blue-green
Copper reduction test
- test for
- principle
Test for glucose to reduce copper sulfate with alkali and heat
- color change progressing from negative blue through green, yellow, and orange/red
Principle of reagent strip for ketones in urine
Sodium nitroprissude reaction
+ purple
Principle for reagent strip for hemoglobinuria
Pseudoperoxidase activity of hemoglobin
+ blue/green
Principle for reagent strip for bilirubinuria
Diazo reaction
+ tan or pink-purple
Ictotest
More sensitive to bilirubin in urine and less subjective to interfering substances
Principle for reagent strip for urobilinogen
Ehrlich’s reaction
+ = red azodye
Watson Schwartz Test
For differentiating urobilinogen and porphobilinogen
- urobilinogen is soluble to both butanol and chloroform
- porphybilinogen is insoluble
Rapid screening test for urine porphobilinogen (> 2mg/dL)
Hoesch test
Principle for Hoesch test
Inverse ehrlich’s test
Substances tested for the detection of bacteriuria
Nitrite
Principle for reagent strip for nitrite
Greiss reaction
(Gram-negative bacteria have nitroreductase)
+ = uniform pink azodye = 100,000 orgm/mL
Significance of leukocyte in urine
UTI
Inflammation
Principle for the reagent strip for leukocyte in urine
Leukocyte esterase
(detect all WBCS except lymphocytes)
+ puple azodye
Microscopic examination of urine : bright-field microscopy
Routine U/A
Microscopic examination of urine : polarizing microscopy
ID of cholesterol in oval fat bodies, fatty acids, crystals
Microscopic examination of urine : phase-contrast microscopy
Visualization of elements with low RI
Microscopic examination of urine : dark-field microscopy
Treponema pallidum
Microscopic examination of urine : interference-contrast
Produced 3F image and layer-by-layer imaging
Stemheimer-Malbin stain
ID WBCs, epithelial cells, and casts
Toluidine Blue
Differentiate WBCs
Lipid Stains (Oil Red O, Sudan III)
ID free fat droplets
Gram stain
ID bacterial casts
Hansel Stain
ID eosinophils
Prussian blue stain
Hemoderisin (yellow-brown)
HYALINE CAST
- reporting
- disease and other conditions
Average per LPF Congestive heart failure Strenuous exercise Heat exposure Emotional stress
RBC CAST
- reporting
- disease and other conditions
Average per 10 HPF
Glomerulonephritis (bleeding within nephron)
Strenuous exercise
WBC CAST
- reporting
- disease and other conditions
Average per 10 HPF
Pyelonephritis (inflamm of renal tubule)
Acute interstitial nephritis
BACTERIAL CAST
- reporting
- disease and other conditions
RFMM per HPF
Pyelonephritis
RTE CAST
- reporting
- disease and other conditions
Average per 10 HPF
Renal tubule destruction
Acute tubular necrosis
MALTESE CROSS appearace
Oval fat bodies
Fatty casts
Starch
GRANULAR CAST
- disease and other conditions
Glomerulonephritis
Pyelonephritis
Stress and exercise
FATTY CAST
- disease and other conditions
Nephrotic syndrome
Toxic tubular necrosis
Diabetes mellitus
Crush injuries
WAXY CAST
- disease and other conditions
Chronic renal failure
Stasis of urine flow
BROAD CAST
- disease and other conditions
Extreme urine stasis Renal failure (destruction of tubular walls)
Most common type of broad cast
Granular and waxy cast
Most common urinary sediment in renal calculi
CaOx
Least common urinary sediment in renal calculi
Cysteine