URINE EXAMINATION Collection (a) Early morning specimen is preferred as it is most concentrated and slightly { acidie which preserves the cells well. Also casts, proteins and sugars are missed out in dilute urine. (b) Random sample ~ can be taken at anytime. (c) 24 hours urine sample- for quantitative analysis. (d) Clean mid-stream catch sample for microbiological examination. done within an hour, refrigerate at 4 degrees centigrade or preservative substances like toluene, } formaldehyde, thymol etc. can be used. Volume~24 hrs. Normal -1.2 ~ 1.5 L (600 ~ 2000 ml / 24 hrs.) Oliguria -< 400 ml /24 hrs. L—; Polyuria - > 3000 ml / 24 hrs. Nocturia - Nocturnal urine output > 400 ml (reduced capacity of bladder) Appearance - Straw coloured ~ because of pigment urochrome. Abnormal colour could be due to pigments Hemoglobin / myoglobin ~ smoky brown colour Bile pigments = deep yellow colour |__| Specific gravity - It reflects the concentration of solutes in urine and is a measure of renal function. Normal specific gravity - 1.003 — 1.030. | Increased in — proteinuria, glycosuria, dehydration, vomiting, burns & shock. [| Decreased - Diabetes insipidus Fixed - 1.010 ~ seen in chronic renal Failure, }—| _ Temp. Correction ~ Add 0.001 for every 3 degree C rise and subtract 0,001 for every 3 degree fall from 20 degree centigrade. | pH- Ranges from 4.8 to 7.6 (av. 6.0) Preservation - It is best if tests are performed immediately or within an hour of collection. If not | Teacher’s Signature :Sugar Presence of sugar in urine is called glycosuna Causes of glycosuria:— Physiological — Pregnancy, lactation. ; 7 Pathological — Diabetes mellitus, renal glycosuria — when the renal threshold itself is lowered. (Normal renal threshold ~ 180 mg/dl), hyperthyroidism Benedict's semiquantitative method of sugar estimation- Semiquantitative as from the end result, you can roughly estimate the amount of sugar present Benedict's reagent ~ contains Copper sulphate, sodium carbonate, & sodium citrate dissolved in distilled water. |e — Sugars reduce cupric sulphate (CuSO,) to Cuprous oxide (Cu 20) which gives the final colour (brick red). Reducing sugars ~ glucose, fructose, galactose, and xylose. Non reducing sugar sucrose. False positive results — ascorbic acid, uric acid, salicylates, formalin. Procedure ~ Take 5 ml of Benedict’s reagent in a test tube and add 8 drops of urine. Mix and bring to boil for 2-3 minutes. | Interpretation - No change in colour - negative Trace ~ greenish blue 1+ (01-05 g/dl) - cloudy green | 2+ (05-1 g/dl) - yellow to orange precipitate. 34+ (1-2 gidl) = orange to red precipitate, | 4+ (22 gidl) - brick-red precipitate. | Advantage ~ Simple and easy to perform. - Semi-quantitation can be done. + very sensitive Other methods - 1) Benedict’s quantitative test 2) Glucose oxidase method- (Glucostix) Glucose Oxidase > -Gluconic acid + 1,0, ‘Glucose + Peroxidase colorless chromogen coloured chromogen + HO.— x i Fi i ) Expt. No. __ Page No,__ 3) Proteins Sv = Excretion of proteins in urine greater than physiological amounts is called proteinuria. za Date 3 Nonmal excretion of urinary proteins ~ 30 mg — 150 mg / 24 hours, Types of proteinuria — i) Functional — small amount, intermittent, no other evidence of renal disease. + Exercise = Exposure to extreme cold = Last few weeks of pregnancy ii) Organic — definite disease association. It is persistent, significant amounts of proteins lost a) Pre-renal = Dehydration bums. - Ascites 4 - Acute febrile illness -j, Severe anemias. 'b)|Renal ~Glomerulonephritis, Pyelonephritis, Nephrotic syndrome (massive) ©)Post renal or false proteinuria Accidental-blood, vaginal discharge, semen (1)Heat and acetic acid test for protein estimation ~ Very sensitive test, | Procedure: Make the urine slightly acidic to litmus by adding dilute acetic acid (3%) drop | by drop. Fill a small test tube three ~ quarters full with urine and heat the top centimeter or two to boiling, Protein if present is coagulated and can be seen by comparing with the tunboiled urine lower down. Comparison should be attempted against a dark background for™| better appreciation Why acidify ~ With alkaline urine alkali-metaproteins are formed which are not coagulated | (false negatives). Also phosphates can be precipitated (False positive). Do not use too much —} acid as it tends to precipitate acid metaproteins. Use of concentrated acids can destroy proteins. ~~ INTERPRETATION — -ve (no proteins) < 0.05 g/dl No cloudiness 1+ 0.05 g/dl Distinct positive turbidity ima 2+ 0.05 — 0.2 g/dl Turbidity + granulation ae ae 02-05 gidl Turbidity + flocculation 4 4+ 205 g/dl Solid pptn.(coagulum formation) Bi) (2) Sulphosalycilic acid test — gl To 3 ml of centrifuged urine sample, add 3 ml of 3% SSA, invert & mix — coagulation if protein present. | (3) Nitric aci test (for small amount of urine) (4) Albustix.Ketone bodies Intermediate products of fat metabolism 1. Acetone 2. Acetoacetate (diacetic acid) 3. B-hydroxy butyrate Causes of ketonuria fa) Non diabetic-Dehydration, acute febrile illness, malnutrition / starvation. b) Diabetes mellitus (uncontrolled) i e. Diabetic ketoacidosis, stress, toxic states, prolonged vomiting, Rothera’s test Principle Acetone and diac produced colour (purple). acid react with Sodium nitroprusside in the presence of alkali to Procedure Take 5 ml of urine in a test (ube and saturate it with Ammoniu ‘adding sinall amounts of Ammonium Sulphate and keep mixing regularly till no more of it dissolves in urine and starts setting down at the bottom of the tube. Avoid frothing while mixing. Then add a tiny crystal of sodium nitroprusside and mix. Then gradually by the sides of the tube, pour liquor ammonia in the tube, A positive test is indicated by a purple ring formed at the interface of urine and ammonia solution, A brown ring has no significance, m Sulphate. To do this, keep on Other tests - Gerhardt’s test (for acetoacetate only), Ketostix. Test for Bile salts Hay’s sulphur test - Take sufficient amount of urine in a wide mouthed container e.g. beaker. Gently sprinkle sulphur powder over it. Presence of bile salts in urine is seen as sinking sulphur particles, seen against light from the sides of the beaker. Principle ~ Bile salts lower the surface tension of urine, Test for Bile pigments and (urobilinogen! Fouchet’s test - Take 5 ml of urine in a test tube. Add half the volume of 10% Barium chloride. Mix and filter. Dry the filter paper and add few drops of Fouchet’s reagent (FeCl, trichloracetic cid and distilled water) ~ Development of green colour indicates a positive test for bile pigments. For urobilinogen, add 1 ml of Ehrlich’s reagent to the filtrate of est, Pi ir denotes a ' r th : ri 5 es of the above test, Pink colour denote:OBSERVATL V NGS D554 P eateis (No. Cloudines) A : Br (\=agiat) Com Steuaaey 2} Pf | Purple Ring E Ormed | Vie ties aul TS] Ts a