chemical exam Flashcards
- Presence in urine provides early indicaiton of liver disease. Detected long before presentation of jaundice
- Principle: Diazo Reaction
- (+) tan/pink/violet
bilirubin
- Indicates disorders affecting the renal tubules.
- Impaired reabsorption
tubular protenuria
- 1 min
- Ehrlich’s reaction
urobilinogen
- May lead to renal failure
- Indicated by MICROALBUMINURIA (which is not detected by rgnt strip)
diabetic nephropathy
- Bile pigment from hemoglobin degradation
- Present in small amount, <1 mg/dL
- Specimen of choice: afternoon urine (2pm to 4pm due to alkaline tide)
- Principle: Ehrlich’s Reaction
urobilinogen
- 30secs
- Double sequential enzymatic reactio
glucose
SSA
clumps of protein
4+
what is the result
Presence of non-albumin protein because the test is sensitive to albumin
false negative
reject urine if pH is (?)
9
due to increased pressure on the renal veins
orthostatic proteinuria
- INVERSE EHRLICH REACTION
- Rapid screening test for PBG (>2mg/dL)
hoesch test
positive results for BLOOD
- Uniformly green/blue: (?)
- Speckled/Spotted: (?)
- Hgb/myoglobin
- hematuria
- 45 secs
- pKa change of polyelectrolytes
specific gravity
it reacts if pH is basic
bromothymol blue
- Consists of weighted float attached to a scale that has been calibrated in terms of urine sp/gr.
- DISADVANTAGES: Requires large urine volume, affected by TEMPERATURE, GLUCOSE and PROTEIN
urinometer (hydrometer)
SSA
turbidity + granulation + flocculation
3+
comparison of velocity of light in air w/the velocity of light in a solution
refractive index
- Differentiation of urobilinogen, porphobilinogen and other Ehrlich-Reactive Compounds.
- Extraction with CHLOROFORM and BUTANO
watson-schwartz test
- Reducing agent
- Causes false negative reactions to: “BB LNG”
ascorbic acid
Based on the principle that the frequency of a soundwave entering a solution changes in proportion to the density of the solution
harmonic oscillation densinometry
Principle: pKa change of polyelectrolytes
reagent strip (dipstick)
Impaired selective filtration due to glomerular damage causing high molecular weight (and negatively charged) substances to escape through
glomerular protenuria
- 40 secs
- Na Nitroprusside Test (Legal’s Test)
ketones
presence of intact RBC
hematuria
- Most indicative of renal disease
- White foam (albumin) upon shaking
- Normally <10mg/dL or 100mg/24hrs. (albumin)
- Principle: (Soresen’s) Error of Indicator
- yellow (-)
- blue to green (+)
- sensitive to ALBUMIN
protein
SSA
distinct turbidity
1+
- Compensated to temperature (no need for correction)
- But still requires correction for Glucose and Proteins
refractometer
- Rapid sreening test for UTI/Bacteuria
- Considered as a valuable test for detecting initial bladder infection (cystitis)
- Performed in parallel with Leukocyte esterase to determine the necessity for urine culture
- SPECIMEN: First morning or 4hour urine
- Principle: Greiss Reaction
nitrite
The most conventional method of urine chemical analysis is carried out through the use of a chemical impregnated plastic strip called
reagent strip
sugars
Increased in pregnancy, lactation and strict milk diet
lactose
harmonic oscillation densinometry
6mL of urine:
IRIS slideless micriscope (?)
IRIS mass gravity meter (?)
- 4 mL
- 2 mL
- 2 mins
- Leukocyte estarse
leukocytes
- High Protein Diet
- Dehydration
- Cranberries
- Diarrhea
- Diabetis Mellitus
- Acid (+) bacte
- Starvation (ketone build up)
- Drugs
- Methamine mandelate
- Fosfomycin tromethamine
causes of acidic urine
SSA
noticeable turbidity
trace
- assessment of kidney’s concentrating ability.
- Defined as the density of a solution compared w/ the density of a similar volume of distilled water at a similar temperature.
- Infulenced by the number and density of particles dissolved in a solution.
specific gravity
- 1 min
- (Soresen’s) error of indicator
proteins
- results from increased FAT METABOLISM due to inability to metabolize carbohydrates.
- Principle: Legal’s Test (Sodium Nitroprusside reaction)
ketones
- 1 min
- Double indicator system
pH
- non reducing sugar
- False (+) in reagent strips but (-) in Copper reduction test
- Increased in intestinal disorders
sucrose
presence of hemoglobin pigment from RBC destruction
hemoglobinuria
sugars
Increased fruits, honey or syrup intake
fructose
sugars
Increased in infants with galactosemia
galactose
what is the result
- Highly alkaline urine interferes w/ the acid buffer (color change unrelated to CHON)
- Long contact of urine to the reagent pad
- Contamination w/ quarternary ammonia compounds, detergent and antiseptics
- High specific gravity
false positive
- Significance: UTI/Inflammation, screen for urine culture specimens.
- Principle: Leukocyte Esterase
leukocyte
Cold precipitation that reacts equally on all forms of proteins
SSA (sulfosalicylic acid) precipitation test
- most frequently tested
- Principle: Double sequential enzymatic reaction
glucose
it reacts if ph is acidic
methyl red
- 30 secs
- Diazo reaction
bilirubin
pH normal values:
- normal catch (?)
- 1st morning (?)
- afternoon (?)
- 4-8 pH
- 5-6 pH
- > 7 pH
- 1 min
- Greiss’s reaction
nitrites
- non-specific test for reducing sugars
- Principle: Copper reduction in the presence of heat and alkali
clinitest/benedict’s test
are High molecular substances and does not relate to renal concentration ability but will increase specific gravity.
glucose and protein (CHON)
- Caused by conditions affecting the plasma prior to its reaching the kidney.
- Not indicative of actual renal damage
- Not detected by reagent strip for CHON because it only detects ALBUMIN
pre-renal proteinuria
- 1 min
- pseudoperoxidase activity of hemoglobin
blood
for detection of microalbuminuria
micral test
- indication of injury on the kidney
- Principle: Pseudoperoxidase activity of Hgb
blood
SSA
turbidity + granulation
2+
store reagent strips in
30 degrees below
sugars
Increased in benign pentosuria
pentose
important indicator for identification of crystals and determination of unsatisfactory spx
pH
- Renal Tubular Acidosis
- Hyperventilation
- High Fiber (Veggies) Diet
- Urease (+) bacte
- After meal
- Old specimen
causes of basic urine
SSA
no increased turbidity
negative
reagent for dipstick
bromothymol blue
reagent for pH
- bromothymol blue
- methyl red
reagent for protein
tetrabomphenol blue
major urinary protein
albumin
clinical protenuria
> 30 mg/dL
proliferation of immunoglobulin producing plasma cells
multiple myeloma
- identified in serum electrophoresis
- in urine: precipitates at 40-60 C (Cloudy)
disoslves at 100 C
BENCE JONES PROTEIN
ALBUMIN EXCRETION RATE
- NORMAL AER = (?)
- Microalbuminuria = (?)
- Clinical Albuminuria = (?)
- 0-20 ug/min
- 20-200ug/min (30-300mg/24hours)
- > 200ug/min
reagent for glucose
- glu oxidase
- peroxidase
color
aminopropylcarbazole
yellow to orange-brown
Ortho-toluidine
pink to purple
glucose interference
Contamination with strong oxidizers and non-reducing sugars
false (+)
glucose interference
contamination/presence of reducing substances such as Vit. C
false (-)
major ketone BUT NOT DETECTED IN REAGENT STRIP.
78% B-hydroxybutyric acid
parent ketone
20% Aceto-Acetic Acid
ketone detected only when GLYCINE is added
2% Acetone
reagent for BLOOD
…hydroperoxidase
color
- (-) pink spots/edges
- (+) uniform pink
nitrite
