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AUBF: Urinalysis 3
Urinalysis 3 Principle: In the presence of aminoacetic acid (glycine), sodium nitroprusside will form a
URINARY KETONES ferropentacyanide colored complex with the isonitro derivative of ketones. Sodium
Ketones phosphate provides an optimum pH, and the lactose enhances the color of this reaction.
represents 3 intermediate products of fat metabolism: Procedure:
1. acetone – 2% 1. Place tablet in a piece of white filter paper.
2. acetoacetic acid – 28% 2. Pour a drop of urine (or blood) on the tablet a Read color at 30 seconds and
3. beta-tiydroxybutyric acid – 78% compare with color chart
normally do not appear in urine Interpretation:
appear when body stores of fat must be metabolized to supply energy
Negative Cream
Trace (.1g/dL) Lavender
Moderate Purple
Strongly (+) Deep purple
Clinical Significance Reagent Strip Method (Ketostix)
1. Diabetic ketoacidosis Principle:
2. Insulin dosage monitoring Follows the sodium nitroprusside decomposition reaction in rothera's test
3. Starvation Reagent:
4. Malabsorption/pancreatic disorders 7.1% sodium nitroprusside; 92.9% buffer
5. Strenuous exercise Procedure:
6. Vomiting 1. Immerse all areas of reagent strip in fresh urine specimen and Remove strip
7. Inborn errors of amino acid metabolism immediately.
most valuable in management and monitoring of IDDM (type 1) 2. Run edge of strip against the rim of the container to remove excess urine.
ketonuria is an early indicator of insuffedent insulin dosage 3. Hold strip and compare the ketone test area closely with the color chart on bottle
↑ ketone → electrolyte imbalance, dehydration → acidosis→diabetic coma label exactly 40 seconds later.
ketone tests are included in all multiple-test strips and also combined with glucose on strips Interpretation
used primarily for at-home testing (-) Test area remains tan colored after 40 sec
Rothera's Test (+)Test area turns pink to purple within 40 sec
Principle: Sodium nitroprusside is decomposed to Na4Fe(CN)6, NaN02, and Fe(OH)3, the Sensitivity:
terropentacyanide forming a red to purple complex with the isonitroamine derivatives of Multistick: 5-10 mg/dL of acetoacetic acid
acetone and diacetic acid. Chemstrip: 9 mg/dL of acetoacetic acid
Reagents: 70 mg/dL of acetone
1. Sodium nitroprusside reagent: False (+): Phthalein dyes
Pulverize and mix 7.5 g of sodium nitroprusside and 200 g of ammonium Highly pigmented red urine
sulfate Levodopa
2. Concentrated ammonium hydroxide Medications containing free sulfhydryl groups
Procedure: False (-) specimens: Improperly preserved
1. To 3-5 ml of urine in a test tube, add approximately l-2g of Rothera's nitroprusside
reagent and dissolve by shaking. URINARY BILE PIGMENTS
2. Overlay with about 1 ml conc. NH4OH Bilirubin
Interpretation: a highly pigmented yellow compound and a degradation product of hemoglobin
A red to purple ring developing within 1 mil. and 30 see, at the junction of the 2 its appearance in urine can provide an early indication of liver disease
layers is a (+) reaction. bilirubin in urine is often detected long before the development of jaundice
A brown ring is NOT a positive reaction Clinical Significance of Urine Bilirubin
If the red to purple color fades during the first 5 minutes, the test is considered (-) 1. Hepatitis
The width of the ring is roughly proportional to the cone, of the ketone bodies 2. Cirrhosis
Recording of results: 3. Other Liver Disorders
4. Biliary obstruction (gallstones, carcinoma)
NEGATIVE No ring or a brown ring
Urine Bilirubin Urine Urobilinoge
Trace to + feint pinking purple ring
Bile duct obstruction +++ Normal
++ narrow dark purple ring
Liver damage + or - ++
+++ wide dark purple ring
Gerhardt's Ferric Chloride Test Hemolytic disease Negative +++
Principle:
Ferric ions chelate with the enol groups of diacetic acid (but not acetone) to produce a red Foam Test
"Bordeaux wine" complex Principle:
Sample: Diacetic add is unstable and wilt oxidize to acetone upon standing. Therefore urine Because lyophilic sols such as bile salts lower the surface tension and because the yellow
should be tested shortly after collection. color of bilirubin, urine containing these substances in increased amounts will readily form
Reagents: 10% aqueous ferric chloride yellow foam when shaken
Procedure: Procedure:
1. To 5 ml of urine in a test tube, add ferric chloride, drop by drop, until no further 1. Shake a small aliquot of urine vigorously in a test tube.
brown to tan (ferric phosphate) precipitate is produced. 2. Observe for yellow foam.
2. Filter. Place a small amount of ferric chloride in a test tube and overlay with urine. Interpretation:
3. If a red "Bordeaux wine" color is produced, boil test tube vigorously for 15 min. Copious yellow foam indicates pathologically increased concentration of bilirubin and salts
Interpretation: Fouchet's Test (Oxidation Method)
(+) "Bordeaux wine" - color disappearing after boiling Principle: The phosphate ions present in urine reacts with the barium in the filter paper to
Acetest method form barium phosphate. Bilirubin is adsorbed on the surface of the barium phosphate, the
AUBF: Urinalysis 3
Urinalysis 3 Principle: In the presence of aminoacetic acid (glycine), sodium nitroprusside will form a
URINARY KETONES ferropentacyanide colored complex with the isonitro derivative of ketones. Sodium
Ketones phosphate provides an optimum pH, and the lactose enhances the color of this reaction.
represents 3 intermediate products of fat metabolism: Procedure:
1. acetone – 2% 1. Place tablet in a piece of white filter paper.
2. acetoacetic acid – 28% 2. Pour a drop of urine (or blood) on the tablet a Read color at 30 seconds and
3. beta-tiydroxybutyric acid – 78% compare with color chart
normally do not appear in urine Interpretation:
appear when body stores of fat must be metabolized to supply energy
Negative Cream
Trace (.1g/dL) Lavender
Moderate Purple
Strongly (+) Deep purple
Clinical Significance Reagent Strip Method (Ketostix)
1. Diabetic ketoacidosis Principle:
2. Insulin dosage monitoring Follows the sodium nitroprusside decomposition reaction in rothera's test
3. Starvation Reagent:
4. Malabsorption/pancreatic disorders 7.1% sodium nitroprusside; 92.9% buffer
5. Strenuous exercise Procedure:
6. Vomiting 1. Immerse all areas of reagent strip in fresh urine specimen and Remove strip
7. Inborn errors of amino acid metabolism immediately.
most valuable in management and monitoring of IDDM (type 1) 2. Run edge of strip against the rim of the container to remove excess urine.
ketonuria is an early indicator of insuffedent insulin dosage 3. Hold strip and compare the ketone test area closely with the color chart on bottle
↑ ketone → electrolyte imbalance, dehydration → acidosis→diabetic coma label exactly 40 seconds later.
ketone tests are included in all multiple-test strips and also combined with glucose on strips Interpretation
used primarily for at-home testing (-) Test area remains tan colored after 40 sec
Rothera's Test (+)Test area turns pink to purple within 40 sec
Principle: Sodium nitroprusside is decomposed to Na4Fe(CN)6, NaN02, and Fe(OH)3, the Sensitivity:
terropentacyanide forming a red to purple complex with the isonitroamine derivatives of Multistick: 5-10 mg/dL of acetoacetic acid
acetone and diacetic acid. Chemstrip: 9 mg/dL of acetoacetic acid
Reagents: 70 mg/dL of acetone
1. Sodium nitroprusside reagent: False (+): Phthalein dyes
Pulverize and mix 7.5 g of sodium nitroprusside and 200 g of ammonium Highly pigmented red urine
sulfate Levodopa
2. Concentrated ammonium hydroxide Medications containing free sulfhydryl groups
Procedure: False (-) specimens: Improperly preserved
1. To 3-5 ml of urine in a test tube, add approximately l-2g of Rothera's nitroprusside
reagent and dissolve by shaking. URINARY BILE PIGMENTS
2. Overlay with about 1 ml conc. NH4OH Bilirubin
Interpretation: a highly pigmented yellow compound and a degradation product of hemoglobin
A red to purple ring developing within 1 mil. and 30 see, at the junction of the 2 its appearance in urine can provide an early indication of liver disease
layers is a (+) reaction. bilirubin in urine is often detected long before the development of jaundice
A brown ring is NOT a positive reaction Clinical Significance of Urine Bilirubin
If the red to purple color fades during the first 5 minutes, the test is considered (-) 1. Hepatitis
The width of the ring is roughly proportional to the cone, of the ketone bodies 2. Cirrhosis
Recording of results: 3. Other Liver Disorders
4. Biliary obstruction (gallstones, carcinoma)
NEGATIVE No ring or a brown ring
Urine Bilirubin Urine Urobilinoge
Trace to + feint pinking purple ring
Bile duct obstruction +++ Normal
++ narrow dark purple ring
Liver damage + or - ++
+++ wide dark purple ring
Gerhardt's Ferric Chloride Test Hemolytic disease Negative +++
Principle:
Ferric ions chelate with the enol groups of diacetic acid (but not acetone) to produce a red Foam Test
"Bordeaux wine" complex Principle:
Sample: Diacetic add is unstable and wilt oxidize to acetone upon standing. Therefore urine Because lyophilic sols such as bile salts lower the surface tension and because the yellow
should be tested shortly after collection. color of bilirubin, urine containing these substances in increased amounts will readily form
Reagents: 10% aqueous ferric chloride yellow foam when shaken
Procedure: Procedure:
1. To 5 ml of urine in a test tube, add ferric chloride, drop by drop, until no further 1. Shake a small aliquot of urine vigorously in a test tube.
brown to tan (ferric phosphate) precipitate is produced. 2. Observe for yellow foam.
2. Filter. Place a small amount of ferric chloride in a test tube and overlay with urine. Interpretation:
3. If a red "Bordeaux wine" color is produced, boil test tube vigorously for 15 min. Copious yellow foam indicates pathologically increased concentration of bilirubin and salts
Interpretation: Fouchet's Test (Oxidation Method)
(+) "Bordeaux wine" - color disappearing after boiling Principle: The phosphate ions present in urine reacts with the barium in the filter paper to
Acetest method form barium phosphate. Bilirubin is adsorbed on the surface of the barium phosphate, the
