biochemical urinalysis dr neeraj

91
URINE BIO CHEMICAL URINE BIO CHEMICAL ANALYSIS & ITS CLINICAL ANALYSIS & ITS CLINICAL SIGNIFICANCE SIGNIFICANCE Presented by Dr Neeraj Nirala GUIDE: Dr Neera Samar UNIT HEAD: Dr R.L Meena SEMINAR PRESENTATION RNT MEDICAL COLLEGE & MB GOVT HOSPITAL

Upload: drneeraj-nirala

Post on 15-Jul-2015

596 views

Category:

Education


3 download

TRANSCRIPT

Page 1: biochemical Urinalysis Dr Neeraj

URINE BIO CHEMICAL URINE BIO CHEMICAL ANALYSIS & ITS CLINICAL ANALYSIS & ITS CLINICAL SIGNIFICANCESIGNIFICANCE

Presented by Dr Neeraj Nirala

GUIDE: Dr Neera Samar

UNIT HEAD: Dr R.L Meena

SEMINAR PRESENTATION

RNT MEDICAL COLLEGE & MB GOVT HOSPITAL

Page 2: biochemical Urinalysis Dr Neeraj

Introduction

URINE : is excretory product from body

The basic steps in urine formation are :

1. Glomerular Filtration2. Tubular Reabsorption 3. Tubular Secretion 4. Excretion.

Page 3: biochemical Urinalysis Dr Neeraj

Composition of normal urine3

Normal urine contains 90-95% water and about 60 G/day of solid constituents which may be organic or inorganic in nature

Page 4: biochemical Urinalysis Dr Neeraj

Organic constituents of urine4

S.No. Constituent Concentration

1. Urea 10-45 mg/dl

2. Uric acid 2.5- 7.0 mg/dl

3. Creatinine 0.6-1.2 mg/dl

Page 5: biochemical Urinalysis Dr Neeraj

Inorganic constituents of urine5

S.No. Constituent Concentration (G/day)

1 Chlorides 10-152 Sodium 3-53 Potassium 2-2.54 Calcium 0.1-0.35 Phosphates 0.8-1.36 Sulphates 1.0-1.27 Ammonia 0.7-0.8

Page 6: biochemical Urinalysis Dr Neeraj

Purpose

General evaluation of health Diagnosis of disease or disorders of the

kidneys or urinary tract Diagnosis of other systemic disease that affect

kidney function Monitoring of patients e.g like diabetes Screening for drug abuse eg. amphetamines

Page 7: biochemical Urinalysis Dr Neeraj

Collection of urine specimens

The first voided morning urine (the most common)

Random urine (for emergency) Clean-catch, midstream urine (for urine

culture) Urinary catheter Suprapubic aspiration Attention Need to be examined within 1-2 hour Free of debris or vaginal secretions

Page 8: biochemical Urinalysis Dr Neeraj

MIDSTREAM URINE COLLECTION

In both sexes atleast 200ml of urine should be passed before collecting a midstream urine specimen without interrupting the urine flow

Gloves should be weared for urinary collection

A sterile urine container should be used Should be clean catch

Page 9: biochemical Urinalysis Dr Neeraj

HOW TO COLLECT

MALES 1. Foreskin is retracted and held back

throughout the collection

2. Urethral meatus is cleansed by moist gauze

Page 10: biochemical Urinalysis Dr Neeraj

FEMALE1. Where possible use vaginal tampon2. Hold labia well separated during collection3. Gently cleanse the periurethral area with

several moistened gauze pieces from anterior to posterior

URINARY CATHETER SPECIMEN: Nearly 200ml urine should be passed before collection of urine

Page 11: biochemical Urinalysis Dr Neeraj

Specimen Collection

Supra-pubic Needle AspirationA fine needle is passed through sterilized suprapubic skin directly into a full bladder.

Uncontaminated urine can then be aspirated

Page 12: biochemical Urinalysis Dr Neeraj

Sample preservation12

There is no single all purpose preservative For determination of urea, ammonia, nitrogen and

calcium- Hydrochloric acid is used (2 N or concentrated HCL)

For determination of sodium, potassium, chloride, bicarbonate, calcium, phosphorus, urea, ammonia, amino acids, creatinine, proteins, reducing substances and ketone bodies- Thymol is used

Toluene is a very satisfactory preservative for urine

Page 13: biochemical Urinalysis Dr Neeraj

Bio-Chemical AnalysisBio-Chemical Analysis

Page 14: biochemical Urinalysis Dr Neeraj

Chemical examination

Urine PH Protein Reducing sugars Ketones Bilirubin Urobilinogen Nitrites Occult blood Beta hcG Certains drugs

Normal constituents Abnormal constituents

Inorganic constituentsChlorideSulphate Calcium ammonia

Organic constituentsUreaCreatinine Uric acid

Page 15: biochemical Urinalysis Dr Neeraj

Analysis of normal constituents

A) Inorganic constituentsi) Test for Urinary chlorides(silver nitrate test)Principle- Silver chloride is precipitated in the

presence of nitric acid and silver nitrate. Procedure-Take 2 ml of urine and add 0.5 ml of

concentrated nitric acid and 1 ml of silver nitrate. A white precipitate of silver chloride appears.

15

Page 16: biochemical Urinalysis Dr Neeraj

Interpretation:

a) Increased Urinary chlorides: Polydipsia, use of diuretics and Addison's disease.

b) Decreased urinary chlorides: Excessive sweating, fasting, diarrhea, excessive vomiting, edema, diabetes Insipidus, infections and adrenocortical hyper function (Cushing's syndrome).

16

Page 17: biochemical Urinalysis Dr Neeraj

2) Test for urinary sulphates

Barium chloride test (test for sulphates)

Principle: Urinary sulphate is precipitated as barium sulphate on reaction with barium chloride solution.

Procedure: Take 3 ml of urine and add 1 ml of conc. HCl and 2 ml of 10% barium chloride. White precipitate indicates the presence of sulphates.

17

Page 18: biochemical Urinalysis Dr Neeraj

Interpretation

a) Increased urinary sulphate: Cystinuria, Homocystinuria, melanuria, obstructive jaundice, hepatocellular jaundice, cyanide poisoning and high protein diet .b) Decreases urinary sulphates are observed in conditions of renal functional impairment.

18

Page 19: biochemical Urinalysis Dr Neeraj

3) Test for Urinary Calcium

Potassium oxalate test (Test for urinary calcium)Principle: With potassium oxalate in acidic medium, calcium is precipitated as calcium oxalate. Procedure: To 2 ml of urine, add 5 drops of 1% acetic acid and 5 ml of potassium oxalate. White precipitate of calcium oxalate is formed.

19

Page 20: biochemical Urinalysis Dr Neeraj

Interpretation:

Increased urinary calcium: Hyperparathyroidism, Hyperthyroidism, Hypervitaminosis D, Multiple myeloma, Renal stones Renal tubular acidosis, Steroids and diuretic therapy

20

Page 21: biochemical Urinalysis Dr Neeraj

Low levels of urine calcium

Malabsortion syndrome hypoparathyroidism thiazide diuretic vitamin D deficeincy

Page 22: biochemical Urinalysis Dr Neeraj

4) Test for Ammonia

Principle : ammonia is evaporated when made alkaline

TEST: To 5ml urine add 2% sodium carbonate till solution is alkaline to litmus

Boil the solution and place a piece of litmus paper at the mouth of test tube.

Colour changes to blueDamp red litmus paper turns blue on exposure to fumes of ammonia.

22

Page 23: biochemical Urinalysis Dr Neeraj

Interpretation:

a) Increased urinary ammonia: Diabetic keto acidosis ingestion of acid forming foods urinary tract infections. b) Decreased urinary ammonia: Alkalosis Nephritis

Page 24: biochemical Urinalysis Dr Neeraj

B) Tests for Organic Constituents

1) Test for Urea (Sodium hypobromite test)Principle: When urea is treated with

sodium hypobromite, it decomposes to give nitrogen.

Procedure: To 2 ml of urine in a test tube, add 4-5 drops of sodium hypobromite.

Observe the effervescence of nitrogen gas.

24

Page 25: biochemical Urinalysis Dr Neeraj

B) Tests for Organic Constituents2) Urease test for ureaPrinciple: Soyabean powder contains the

enzyme urease. This enzyme under pH 7-8 and temperature 550C decomposes urea in to ammonia and carbon dioxide which together form ammonium carbonate (alkaline component) which changes the slightly acidic reaction(yellow color) to alkaline reaction(pink color).

25

Page 26: biochemical Urinalysis Dr Neeraj

B) Tests for Organic Constituents3.Biuret test for ureaPrinciple : Urea when heated decomposes with

the liberation of ammonia and the formation of biuret. Biuret is dissolved in water and develops a violet color forming a complex with alkaline copper sulphate solution.

26

Page 27: biochemical Urinalysis Dr Neeraj

Interpretation:

a) Increased urinary urea: Fever, diabetes mellitus, excess of adrenocortical activity

b) Decreased urinary urea: Liver diseases, metabolic or respiratory acidosis, nephritis

27

Page 28: biochemical Urinalysis Dr Neeraj

ii) Tests for Creatinine

a) Jaffe’s Reaction (Test for creatinine)

Principle: Creatinine reacts with picric acid in the alkaline medium to form a reddish colored complex of creatinine picrate

Procedure: Take 5 ml of urine and add an aqueous solution of picric acid. Make the mixture alkaline with NaOH solution. A red color is produced.

28

Page 29: biochemical Urinalysis Dr Neeraj

ii) Tests for Creatinine

b) Nitroprusside testTo 5 ml of urine add a few drops of sodium

nitroprusside and make the solution alkaline with sodium hydroxide (NaOH).

A ruby red color is formed that turns yellow.This test is also called Wey’s test.

29

Page 30: biochemical Urinalysis Dr Neeraj

ii) Tests for Creatinine

c) Nitroprusside -Acetic acid test (Salkowaski test)

Procedure : Take 5 ml of urine, add a few drops of sodium nitroprusside and then make the solution alkaline with NaOH. A ruby red color is formed that turns yellow.

To the yellow precipitate, add an excess of acetic acid and heat the solution.

A green color is obtained that turns blue upon standing.

30

Page 31: biochemical Urinalysis Dr Neeraj

ii) Test for Creatinine

Interpretation: a) Creatinuria- Creatinuria occurs in uncontrolled

diabetes mellitus, thyrotoxicosis, myasthenia gravis, starvation, infancy, pregnancy, muscular disorders and in growing period.

b) Decreased urinary creatinine: Renal failure

31

Page 32: biochemical Urinalysis Dr Neeraj

Creatinine clearance ( CLcr)

Measurement of GFR Done on 24 urine sample GFR can be estimated by using Cockcroft-

Gault formula for creatinine clearance CLcr (ml/min)= 140 – age/ serum creatinine x

body weight in kg/72 (females multply wt by 0.85)

USES : for adjusting of drug doses To predict the remaining renal function To time and plan the placement of dialysis

Page 33: biochemical Urinalysis Dr Neeraj

iii) Tests for Uric acid

a) Phospho tungstic acid test (For uric acid)

Principle: Uric acid is a reducing agent in alkaline medium. It reduces phospho tungstic acid to tungsten blue.

Procedure: Take 2 ml of urine, add a few drops of phospho tungstic acid reagent followed by a few drops 20% sodium carbonate. Observe the appearance of blue color

33

Page 34: biochemical Urinalysis Dr Neeraj

iii)Tests for Uric acid

b) Benedict’s testPrinciple- Uric acid is soluble in alkali. The blue

color is developed due to the reduction of phospho tungstic acid by uric acid.

Procedure : To 2 ml of urine , add a few drops of Benedict’s uric acid reagent and add a pinch of anhydrous sodium carbonate and mix. A deep blue color indicates the presence of uric acid.

34

Page 35: biochemical Urinalysis Dr Neeraj

SIGINIFICANCE

HIGH LEVELS metastasis Disease that results in breakdown of muscle fibers

(rhabdomyolysis) Disorders that affect the bone marrow (myeloproliferative

disorder) Fanconi syndrome Gout andHigh-purine dietLOW LEVELS

Kidney disease both AKI and CKD

Page 36: biochemical Urinalysis Dr Neeraj

Abnormal constituents

Urinary pH/ reaction Reaction reflects ability of kidney to maintain

normal hydrogen ion concentration in plasma & ECF

Normal urine is acidic, pH ranges between 4.5-8.0 with a mean of 6.0 in 24 hours

Page 37: biochemical Urinalysis Dr Neeraj

Measurement of urinary pH37

Urinary pH is measured by-

pH papers Litmus papers

Page 38: biochemical Urinalysis Dr Neeraj

Variations of urinary pH

A) Acidic urine- Physiologically, It is found after A protein rich diet Heavy exercisePathologically Ketosis-diabetes, starvation, fever Systemic acidosis UTI- E.coli Acidification therapy

Page 39: biochemical Urinalysis Dr Neeraj

Alkaline urine

Strict vegetarian Systemic alkalosis UTI- Proteus Alkalization therapy

Page 40: biochemical Urinalysis Dr Neeraj

Determination of protein in urine

Principle :All the methods are based on the principle of precipitation of protein by chemical agents or coagulation by heat.

Qualitative tests Heat and acetic acid test Sulphosalicyclic acid test Heller’s nitric acid test

NOTE : Turbid urine should be filtered or centrifuged and supernatant should be used

Page 41: biochemical Urinalysis Dr Neeraj

Quantitative test for albumin

Qualitative test and semi quantitative test have limitation that they can’t detect the exact amount of protein excretion. So quantitative test is done on 24 hr urine

2 methods are used for this purpose which uses picric acid for precipitation in different proportion methods are: 

1.Esbach’s method : most commonly used2.Aufrecht’s method

Page 42: biochemical Urinalysis Dr Neeraj

1.Heat and Acetic Acid Test 

1. Place 5 to 10 ml of clear urine in test tube2. Boil the upper portion over a flame.3. If turbidity develops add 1-2 drops of glacial acetic

acid. Sometimes turbidity may be due to phosphate or carbonate precipitation.it is so then glacial acetic acid clear up the turbidity if it is due to protein then precipitation will be there after the addition of acetic acid

4. Reboil the specimen5. If turbidity is present protein is present .if there is

no turbidity at upper portion then protein is absent

Page 43: biochemical Urinalysis Dr Neeraj

G ra d ing o f turbid ity

Negative : No cloudiness Trace: Barely visible cloudiness. 1+ : definite cloud without granular flocculation 2+ : heavy and granular cloud without granular

flocculation 3+ : densed cloud with marked flocculation. 4+ : thick curdy precipitation and coagulation-

Page 44: biochemical Urinalysis Dr Neeraj

2) Sulphosalicylic acid test44

Principle: Negatively charged sulpho salicylic acid neutralizes the positive charge on proteins causing denaturation, and hence precipitation of proteins.

Procedure: To 1 ml of urine add 3 drops of 20% Sulphosalicylic acid. A turbidity or precipitate indicates the presence of proteins.Absence of cloudiness means absence of proteins.

Page 45: biochemical Urinalysis Dr Neeraj

Test for proteins45

S.No. Observation Inference (Approximate protein concentration) mg/100 ml

1) Barely visible turbidity 52) Distinct turbidity 10-303) Moderate turbidity 40-1004) Heavy Turbidity 200-5005) Heavy

flocculent/precipitation500

Page 46: biochemical Urinalysis Dr Neeraj

3) Heller’s Nitric acid ring test46

Principle: Concentrated HNO3 causes denaturation and hence precipitation of proteins.

Procedure: Take 3-5 ml of concentrated nitric acid. Incline the tube and to it add carefully, 2-3 ml of urine, so that it forms the upper layer without disturbing the lower HNO3 layer. In a positive reaction, a white zone of precipitate protein will appear at the junction of two liquids.

Page 47: biochemical Urinalysis Dr Neeraj

Quantitative test: ESBACK’S test Reagent : dissolve 5g of picric acid with 10g of

citric acid in 500ml waterProcedure: fill an Esbacks albuminometer with

urine to mark U. Add reagent to mark R. Close with a rubber stopper, invert several times znd set aside in cool place for 24 hrs. Read off the results according to the marking on the tube which shows albumin in g/L .

Principle: albumin + picric acid= albumin piariate (get deposited)

Page 48: biochemical Urinalysis Dr Neeraj

Precautions

1. If SG of urine > 1.030 urine should be diluted with water, otherwise albumin picrate formed will not settle down

2. If turbid urine, it should be filtered

3. If urine alkaline it should be acidifiedwith 3% acetic acid otherwise acidity of esback’s reagent will be neutralised

ESBACK’S ALBUMINOMETER

Page 49: biochemical Urinalysis Dr Neeraj

MARKING’S IN ESBACK’S ALBUMINOMETER

LOWER PART

UPPER PART

Page 50: biochemical Urinalysis Dr Neeraj

Tests for proteins50

Interpretation- Insignificant amounts of proteins are excreted in urine in normal health not exceeding 20-80 mg/dl. This small amount is not detectable by routine methods. Under certain conditions, as much as 20 G or more proteins may be excreted per day in urine.The most common type of proteinuria is albuminuria; hence proteinuria and albuminuria are used synonymously.

Page 51: biochemical Urinalysis Dr Neeraj

Proteinuria51

When proteins appear in urine in detectable amounts, it is called proteinuria. It can be caused by-a) Increased glomerular permeabilityb) Reduced tubular reabsorptionc) Increased secretion of proteinsd) Increased concentration of low molecular weight proteins in the plasma

Page 52: biochemical Urinalysis Dr Neeraj

Proteinuria

Urine protein composition ( total 150mg/day in adults )

1. Tamm-horsfall protein 70 mg 2. Blood group related antigen 35 mg 3. Albumin 15 mg4. Mucopolysaccharide 15 mg5. Immunoglobulins 5 mg6. Rest hormones and enzymes 10 mg

Page 53: biochemical Urinalysis Dr Neeraj

Proteinuria53

Proteinuria may be- Physiological or Pathological

I) Physiological ProteinuriaCauses include- Violent exercise Pregnancy Postural Alimentary Exposure to cold

Page 54: biochemical Urinalysis Dr Neeraj

Proteinuria54

II) Pathological proteinuriaI. Pre Renal: Severe dehydration Heart diseases Ascites (due to increased intra-abdominal

pressure) Severe anemia, and Fever Collagen diseases Toxemia of pregnancy

Page 55: biochemical Urinalysis Dr Neeraj

Proteinuria55

II. Renal: All inflammatory, degenerative or destructive diseases of kidney; the most common ones are:

Nephrotic syndrome Pyelonephritis Acute and Chronic glomerulonephritis Nephrosclerosis Tuberculosis of kidney Renal failure.

Page 56: biochemical Urinalysis Dr Neeraj

Proteinuria56

III. Post Renal – Also called false proteinuria because in these conditions proteins do not pass through the kidneys.Causes include-Severe urinary tract infectionsInflammatory, degenerative or traumatic lesions of pelvis, ureters, bladder, prostate or urethraBleeding genito urinary tractPus in urineContamination of urine by semen or vaginal secretions

Page 57: biochemical Urinalysis Dr Neeraj

During heat and acetic acid

If cloudiness is seen it may be due to phosphate or carbonates confirm by adding 3% glacial acetic acid. if it is due to protein cloudiness persist and if it is due to the phosphate the cloudiness disappears and if it is due to carbonate cloudiness disappears with effervescence.

If cloudiness is disappeared when nitric acid is added then it is due to mucin and nucleoprotein. 

If cloudiness appears with the tube is being heated but disappears when boiling point is reached bence jones protein is present

Page 58: biochemical Urinalysis Dr Neeraj

Bence Jone’s proteins58

Bence Jone’s proteins are light chain immunoglobulins

Excreted in urine of a patient suffering from multiple myeloma

These proteins precipitate between 40-60 degree centigrade

Upon further heating, turbidity disappears to reappear on cooling

These proteins redissolve on boiling unlike albumin

Page 59: biochemical Urinalysis Dr Neeraj

Tests for reducing sugars59

1) Benedict’s TestPrinciple :Benedict's reagent contains sodium

carbonate, copper sulphate and sodium citrate.

In the alkaline medium provided by Sodium carbonate, the copper remains as cupric hydroxide. Sodium citrate acts as a stabilizing agent to prevent precipitation of cupric hydroxide.

In alkaline medium, sugars form enediols, cupric ions are reduced, and corresponding sugar is oxidized to sugar acid.

Page 60: biochemical Urinalysis Dr Neeraj

Tests for reducing sugars60

Benedict’s testProcedure: Take 5 ml of Benedict's

reagent, add 8 drops of urine. Boil for 2 minutes or keep it in the boiling water bath for 5 minutes. A light green, yellow or brick red color is produced depending on concentration of urinary glucose.

Negative test

Positive test

Page 61: biochemical Urinalysis Dr Neeraj

Tests for reducing sugars61

ObservationsBenedict‘s test is a semi quantitative test. The color of the precipitate gives a rough estimate of the reducing sugars present in the given sample. Green color - Up to 0.5 g%Green precipitate - 0.5-1.0 g%(+)Yellow precipitate -1.0-1.5 g% (++)Orange precipitate- 1.5-2.0 g% (+++) Brick red precipitate- >2.0 g% (++++)

Page 62: biochemical Urinalysis Dr Neeraj

Tests for reducing sugars62

2) Fehling Test Another reduction test Contains KOH and Sodium potassium Tartrate

in place of Sodium carbonate and sodium citrate in Benedict’s reagent

Not used any more, since it is less sensitive, less specific and the strong alkali causes caramelisation of the sugars present in the given sample.

Page 63: biochemical Urinalysis Dr Neeraj

Tests for reducing sugars63

Interpretation: Positive Benedict's test signifies Glycosuria. Glycosuria is a non-specific term. Any reducing

sugar found in urine is denoted by glycosuria

Lactosuria - in lactose intolerance Galactosuria - in galactosemia Fructosuria - in hereditary fructose

intolerance Pentosuria - in essential Pentosuria

Page 64: biochemical Urinalysis Dr Neeraj

Glycosuria64

Causes of Glucosuria are: (Glucosuria and Glycosuria are used synonymously)a. Renal glycosuria- pregnancy, hereditary, diseases of renal tubules, heavy metal poisoning .b. Diabetes mellitus c. Alimentary glucosuria d. Hyperthyroidism, hyperpituitarism and hyperadrenalism e. Stress, severe infections, increased intracranial pressure

Page 65: biochemical Urinalysis Dr Neeraj

Glycosuria65

Examples of non-carbohydrate substances which give a positive Benedict's reaction are: a) Creatinine b) Ascorbic acid c) Glucuronates d) Drugs: Salicylates, PAS and Isoniazid

Page 66: biochemical Urinalysis Dr Neeraj

Tests for Ketone bodies66

Rothera’s TestPrinciple: Nitroprusside in

alkaline medium reacts with a ketone group to form a purple ring. It is given by acetone and acetoacetate, but not by Beta hydroxy butyric acid.

Page 67: biochemical Urinalysis Dr Neeraj

Tests for Ketone bodies67

Procedure: Saturate 5 ml of urine with solid ammonium

sulphate and add 0.5 ml of freshly prepared sodium nitroprusside (5%).

Mix well and add liquor ammonia from the side of tube.

A purple ring at the junction of the liquid indicates the presence of ketone bodies.

Page 68: biochemical Urinalysis Dr Neeraj

2) Gerhardt’s ferric chloride test

68

Principle: A purplish color is given by aceto acetate. On boiling acetoacetate is converted to acetone and does not give this test positive.

This test is only given by acetoacetate and not by beta hydroxy butyric acid directly.

Page 69: biochemical Urinalysis Dr Neeraj

Tests for Ketone bodies69

Procedure- Add 10% ferric chloride solution drop by drop to 5 ml of urine in a test tube. If phosphates are present, precipitates of ferric phosphates may form, that should be filtered off and the ferric chloride is added. False positive Gerhardt’s test may be obtained with Salicylic acid and Salicylates.

Page 70: biochemical Urinalysis Dr Neeraj

Tests for Ketone bodies70

3) Test for β- OH butyric acid• No direct test for β- OH butyric acid• Indirect test is performedProcedure : Add a few drops of Acetic acid to

urine diluted 1:1 with distilled water. Boil for a few minutes to remove acetone and aceto acetic acid.

Add about 1.0 ml of H2O2, warm gently, cool, and perform Rothera’s test .

Page 71: biochemical Urinalysis Dr Neeraj

Tests for Ketone bodies71

Acetone, acetoacetate and beta hydroxy butyrate are the ketone bodies. Ketonemia and hence ketonuria occurs mostly in conditions of glucose deprivation. Causes of Ketonuria: 1) Uncontrolled diabetes mellitus 2) Starvation 3) High fat feeding 4) Heavy exercise 5) Toxemia of pregnancy

Page 72: biochemical Urinalysis Dr Neeraj

Tests for bile pigments 72

1) Fouchet’s test Principle: BaCl2 reacts with sulphate in urine to

form barium sulphate. If bilirubin is present in urine, it adheres to precipitate and is detected by oxidation to form biliverdin (Green) with FeCl3 in the presence of trichloro acetic acid. Nitric acid oxidizes bilirubin to biliverdin giving different colors from green to violet.

Page 73: biochemical Urinalysis Dr Neeraj

Tests for bile pigments 73

1) Fouchet’s test Procedure: Take 5 ml of 10% BaCl2 to 10 ml

of urine and filter. Dry the filter paper and add a few drops of Fouchet's reagent (Prepared by adding 10 mg of 10% FeCl3 to 100 ml of 25% TCA). A green color is obtained due to oxidation of bilirubin to biliverdin.

Page 74: biochemical Urinalysis Dr Neeraj

Tests for bile pigments 74

2) Gmelin’s test Principle: Nitric acid oxidizes Bilirubin to Biliverdin giving different colors from green to violet.

Procedure: To about 5 ml of concentrated HNO3

in a test tube, add an equal volume of urine carefully so that the two liquids do not mix. At the junction of two liquids various colored rings (Green, blue, red, violet etc.) will be formed.

Page 75: biochemical Urinalysis Dr Neeraj

Tests for bile pigments 75

3) Iodine testProcedure : Dilute some tincture of iodine with

one to two volumes of water and layer it carefully on to some urine in a test tube, a green ring at the junction of two fluids indicates the presence of Bilirubin.

It is not a sensitive test, can not detect small amount of bilirubin present in the given sample.

Page 76: biochemical Urinalysis Dr Neeraj

Tests for bile pigments76

Interpretation Bilirubin in urine means increased amount of

conjugated bilirubin because unconjugated bilirubin is water insoluble and is also bound to albumin, hence cannot cross the glomerular membrane.

Causes of bilirubinuria are: 1) Moderate to severe hepatocellular damage 2) Obstruction of bile duct- Intra or extra hepatic In prehepatic jaundice, bilirubin is absent in urine.

Page 77: biochemical Urinalysis Dr Neeraj

Test for Bile salts77

Hay’s Sulphur test Principle: Bile salts lower the surface tension

allowing the sulphur powder to sink

Procedure: Sprinkle a little dry sulphur powder on the surface of fresh urine in a test tube taking distilled water as control. Sulphur powder sinks in the presence of bile salts.

Page 78: biochemical Urinalysis Dr Neeraj

Test for Bile salts78

Control for comparison

Positive test

In the control, sulphur powder remains immiscible with the underlying liquid.

In the positive test, the sulphur powder sinks to the bottom. Interpretation: Bile salts and bile pigments are present in urine in obstructive jaundice.

Page 79: biochemical Urinalysis Dr Neeraj

Test for Urobilinogen79

Ehrlich’s test Principle: The test for urobilinogen is based on

the Ehrlich Aldehyde Reaction.

P-dimethylaminobenzaldehyde in an acid medium with a color enhancer reacts with urobilinogen to form a pink-red color.

The optimum temperature for testing is 22° - 26°C.

Page 80: biochemical Urinalysis Dr Neeraj

Test for Urobilinogen80

Ehrlich’s testProcedure: Take 5 ml of fresh urine in a test tube and add 5

ml of Ehrlich's reagent to it. Wait for 10 minutes and add 10 ml of saturated sodium acetate solution.

A pinkish color indicates the presence of urobilinogen.

Page 81: biochemical Urinalysis Dr Neeraj

Test for Urobilinogen81

Interpretation: Urobilinogen is found in urine in hepatic and

prehepatic jaundice.

It is present in excessive amount in prehepatic jaundice and is completely absent in post hepatic jaundice.

An increased urobilinogen concentration in urine is a sensitive index of liver dysfunction or hemolytic disorders.

Page 82: biochemical Urinalysis Dr Neeraj

Test for blood 82

Benzidine TestPrinciple: Hydrogen peroxide liberated from Hb oxidizes Benzidine to form a colored derivative. Procedure: To 3 ml of saturated Benzidine solution in glacial acetic acid, add 2 ml of urine and add 1 ml of 3% H2O2. A blue or green color develops within 10 minutes indicating the presence of blood. Color developing after 10 minutes is not a positive test but it is due to oxidation of Benzidine by atmospheric oxygen.

Page 83: biochemical Urinalysis Dr Neeraj

Test for blood 83

Interpretation: Presence of blood in urine is called hematuria. a. Gross hematuria: Urine appears reddish in gross hematuria and

this is observed in renal stones, malignancies, trauma, tuberculosis and acute glomerulonephritis.

Page 84: biochemical Urinalysis Dr Neeraj

Test for blood84

b. Microscopic hematuria:

Blood is not visible to naked eyes. It is observed in: Malignant hypertension, Sickle cell anemia, Coagulation disorders, Polycystic kidney disease, Incompatible blood transfusion, Auto immune hemolytic anemia.

Page 85: biochemical Urinalysis Dr Neeraj

Biochemistry dept MBGH Central lab URINE

ANALYZER

Page 86: biochemical Urinalysis Dr Neeraj

URINE DIPSTICK READ AT 60 SEC

Page 87: biochemical Urinalysis Dr Neeraj

URINE REPORT BY CENTRAL LAB

PARAMETERS

1.SG2.PH3.LEUCOCYTES4.NITROGEN5.PROTEIN6.GLUCOSE7.KETONES8.UROBILINOGEN9.BILIRUBIN10.ERYTHROCYTES11.COLOUR

Page 88: biochemical Urinalysis Dr Neeraj

Urine pregancy test beta hCG detection

Rapid and easy method Commercial UPT kits are available

based on beta hCG detecttion Principle :The pregnancy testing

device contains a unique set of dye-conjugated and immobilized antibodies used to produce a distinctive visual pattern indicating elevated concentration of hCG (=25 mIU/ml) in the test sample

Page 89: biochemical Urinalysis Dr Neeraj

Example of Results

Page 90: biochemical Urinalysis Dr Neeraj

SUBSTANCE URINE

Alcohol 6–24 hours Note: Alcohol tests may measure ethyl glucuronide, which can stay in urine for up to 80 hours

Amphetamines(except methamphetamine) 1 to 3 days

Methamphetamine 3 to 5 daysMDMA (Ecstasy) 3 – 4 days

Barbiturates(except phenobarbital) 1 day

Phenobarbital 2 to 3 weeks

Benzodiazepines Therapeutic use: up to 7 days. Chronic use (over one year): 4 to 6 weeks

Cannabis Infrequent users: 7-10 Days; Heavy users: up to 30 days;

Cocaine2 to 5 days (with exceptions for heavy users who can test positive up to 7–10 days, and individuals with certain kidney disorders)

TOX SCREEN :Detection of illicit drugs in urine( most commonly)

Page 91: biochemical Urinalysis Dr Neeraj

ThankThank you you