Macroscopic and Microscopic Urinalysis Physical properties of urine

Macroscopic and Microscopic Urinalysis

Physical properties of urine 1. Quantity: The amount of urine to be examined is measured in the graduated cylinder. 2. Colour: The color of normal urine varies between light and dark yellow depending on the type and amount of pigments in the color. 3. Appearance: The appearance of normal fresh urine is obvious. 4. p. H: Normal urine is slightly acidic. The urine p. H ranges from 5. 5 to 6. 5. Urine p. H is determined by litmus paper. 5. Density: The normal urine density ranges from 1. 010 to 1. 030 g/cm 3.

Urinary Microscopic Analysis Preparation of urine sample 1. 10 ml urine sample is taken into a centrifuge tube. 2. It is centrifuged at 1500 rpm for 5 minutes to precipitate urine sediment. 3. The upper part of the liquid is poured. 4. The sediment is taken on a clean slide and examined on a microscope.

Determination of salt in urine (Mohr test) • Principle: The silver nitrate bind to the sodium chloride in urine sample and silver chloride is formed. When there is no sodium chloride in reaction, the excess amount of silver is reacted with potassium chromate and the brick red color silver chromate is formed. • Material: Urine

Determination of salt in urine (Mohr test) Experimental procedure: 1. 2 ml of urine is taken into an erlenmeyer, 3 -4 drops of potassium chromate and 10 drops of distilled water are added. 2. It is titrated with 0. 1 N Ag. NO 3. After each drip, the tube is shaken and mixed. 3. First a white precipitate followed by a brick red color was observed. The presence of red color indicates that the reaction is complete. 1 ml of 0. 1 N Ag. NO 3, 1 ml of 0. 1 N Na. Cl is equal to 0. 00585 g of salt. The amount of Na. Cl in 2 ml urine is calculated as g/L according to the amount of ml of spent silver nitrate.

Tests for determination of protein in urine Tanret test Principle: Based on the principle of precipitation of protein with tanret indicator, which contains mercury ions Material: Urine Experimental procedure: 1. Urine sample in the tube is rotated while being heated in the bunsen flame. 2. Turbidity or no change can be observed in urine after heating. 3. After the addition of Tanret solution, formation of turbidity or an increase in turbidity indicates that protein is present in the urine.

Tests for hidden blood in urine • Benzidine test Principle: Hemoglobin catalyzes the oxidation of benzidine to ‘benzidine blue’ in the presence of H 2 O 2. • Material: Urine • Experimental procedure: 1. 1 ml of urine and 4 ml distilled water are added in a test tube. 2. And then 1 ml benzidine dihydrochloride, 1 ml H 2 O 2 and 1 ml sodium acetate are added. The green, blue-green or blue color indicates that hemoglobin is present in urine.

Tests for hidden blood in urine O-Toluidin • Principle: Hemoglobin forms blue colour with o-toluidin in the presence of H 2 O 2. • Material: Urine Experimental procedure: 1. 5 ml urine+ 2 drops o-toluidin and acide-peroxide solution 2. The presence of blue and blue-green color indicates that test is positive

Tests for digestion disorder OBERMEYER TEST (for indican analysis): • Principle: The principle of the experiment is that the indican converted to indoxyl with HCl, and the created indoxyl converted to indigo blue coloured compound with Fe. Cl 3. Material: Urine Experimental procedure: 1. Add 5 ml urine + 5 ml obermayer indicator in a tube and mix. 2. Add 2 -3 ml chloroform and mix again. Blue colored chloroformed at the bottom of tube indicates the presence of indican.

Test for bilirubin in urine (Smith-Rosin Test) Principle: Bilirubin combined with iodine to form a green compound. Material: Urine Experimental procedure: 1. 5 ml of urine is taken into a test tube. 2. 12 ml of iodine ethyl alcohol solution is added on it by keeping the tube inclined. The formation of a green ring between the two layers indicates that bilirubin presence in the urine.

Test for urobilinogen in urine (Wallace-Diamond Deneyi) Principle: Erlich aldehyde reagent forms a rose pink compound with urobilinogen that can only be found in fresh urine Material: Urine Experimental procedure: 1. 10 ml of urine is taken into a experimental tube 2. Add 1 ml of erlich aldehyde reagent on it. The tube is heated briefly in a hot water bath. The resulting rose pink color indicates urobilinogen.

Test for urobilin in urine (Schlesinger Test) • Principle: I 2 in the lugol solution oxidizes urobilinogen to urobilin and the urobilin forms a green fluorescent complex with zinc acetate in ethyl alcohol solution. • Material: Urine Experimental procedure: 1. 10 ml of urine is taken into a test tube. Put a few drops of lugol solution on it. 2. Then 10 ml of alcoholic zinc acetate solution is added and mixed. 3. Green fluorescence indicates the presence of urobilin when exposed to sunlight on a black background. The intensity of fluorescence is directly proportional to the intensity of urobilin.

References • Ankara University Faculty of Pharmacy Biochemistry Practice Book - 2004 • Basic Concepts in Clinical Biochemistry: A Practical Guide - 2018 - V. Kumar, K. D. Gill