Physical examination of urine

Physical examination of urine along with detailed formation, composition and methods of sample collection and preservation

1. Physical Examination Of Urine By : Dr . Amita Yadav MBBS, MD(Pathology)

2. Urine- Is an ultrafiltrate of plasma from which glucose, amino acids, water and other substances essential to body metabolism have been reabsorbed .

3. Formation of urine--- In the normal adults approx. 1200 ml of blood perfuses the kidney each minute . That is 25% of the cardiac output . The glomeruli receive blood through afferent arterioles and an ultrafiltrate of the plasma passes into the bowman’s space. From there the filtrate is passed through the tubules and the collecting ducts. Reabsorption and secretion of various substances . Concentration of urine occurs . 180 lt of glomerular filtrate in 24 hrs is reduced to 1-2 lt .

4. Urine consists of --- (96%) water Inorganic: Cl - , Na, K. trace amounts of: sulfate, HCO 3 etc.) (4%) dissolved solids: (2%) Urea : ( half) (2%) Other compounds Organic: creatinine uric acid

5. Importance of urine analysis--- 1. General evaluation of health 2. Diagnosis of disease or disorders of the kidneys or urinary tract 3. Diagnosis of other systemic disease that affect kidney function. 4. Monitoring of patients with diabetes 5. Screening for drug abuse both as a part of rehabilitation and in the world of professional sports. 6. To determine pregnancy in women.

6. Examination Of Urine--- Three steps : First: physical characteristics of urine are noted and recorded. Second: series of chemical tests is run. Third: urine sediment is examined under microscope to identify the components of sediments.

7. Sample Collection--- random specimen most commonly received specimen First morning urine the ideal screening specimen used for routine screening, pregnancy tests and for determining orthostatic proteinuria Fasting Specimen (Second Morning Specimen) second voided urine specimen used for glucose monitoring 24-hour specimen timed specimen is used to determine concentration of a particular substance Instruction: Day 1 – 7am patient voids and discards specimen patient collects all urine for the next 24 hours Day 2 – 7am patient voids and adds this urine to the previously collected urine

8. Catheterized Specimen used for bacterial culture Midstream Clean-Catch Specimen an ideal specimen for routine screening and for bacterial culture patient is instructed to cleanse thoroughly the genitalia and is asked to collect the midstream portion of urine. When collecting, patient should be instructed to separate the labia in females or retract the foreskin in uncircumcised males. Suprapubic Aspiration used for bacterial culture and cytology sterile needle is introduced into the bladder to collect sample that is free of contaminants Pediatric Specimen soft, clear plastic bag with adhesive is attached to the genital portion

9. Suprapubic aspiration-

10. Truly representative sample: it is necessary to regulate: time of collection, length of collection period, patient's dietary, medical intake and method of collection. Initial morning sample is preferred (particularly for protein analysis) because they are more concentrated from overnight retention in bladder .

11. Preservatives used-- 1. Hydrochloric acid 2. Toluene 3. Boric acid 4. Thymol 5. Formalin

12. Properly labeled specimen--- Patient’s full name Age and sex Date of collection Time of collection

13. Specimen Evaluation--- Before proceeding with any examination urine sample must be evaluated in terms of acceptability. It includes-proper labeling -proper specimen for requested examination. -proper preservative -visible signs of contamination -transportation delay.

14. Time of analysis: - must analyzed within 1hour at room temperature or within 8hours at 2 o C- 8 o C. - If not assayed within these time limits, several changes will occur.

15. Direct visual observation. Normal fresh urine: Colour : pale or amber Appearance- clear. Volume :750 - 2000 ml/24hr. Physical Characteristics:

16. Physical examination involves: Colour Transparency Odor Volume pH Specific gravity

17. 1. Colour - Normal urine is clear , pale or straw colour due to urochrome pigment . Increases during - Fever - Thyrotoxicosis - Starvation ( Small amounts of urobilins and uroerythrin .) Factors affecting colour of urine are- -Fluid balance -Diet -Medicines and -Diseases ABNORMAL COLOURS : a. COLOURLESS – after ingestion of large amount of water, polyuria . b. DEEP AMBER – after exercise, high grade fever. c. DEEP YELLOW- Jaundice

18. ABNORMAL COLOURS : a. COLOURLESS – after ingestion of large amount of water, polyuria . b. DEEP AMBER – after exercise, high grade fever. c. DEEP YELLOW- Jaundice

19. d. ORANGE BROWN- excreted urobilinogen is colourless , but it is converted in presence of light and low pH to urobilin . e. RED/PINK – in heamoglobinuria , haematuria , myoglobinuria and porphyria . f. DARK BROWN / BLACK- in alkaptonuria . g. GREEN- phenol poisoning h. MILKY- presence of chyle , fat.

20. Silver or milky appearance ----- Pus, bacteria or epithelial cells Yellow foam ---- Bilirubin Orange, green, blue or red ---- Medications Vitamin B supplements can turn urine bright yellow. Cola coloured urine---- Rhabdomyolysis

21. Hematuria -

22. In jaundice-

23. Pyuria -

24. Chyluria -

25. 2- Transparency: Urine is normally clear. Bacteria, blood, sperm, crystals, or mucus can make urine look cloudy. Turbidity may be due to precipitation of crystals or non pathologic salts. Amorphous phosphate ,ammonium urate and carbonate precipitate in alkaline urine. Uric acid and urates cause white,pink or orange cloud in acidic urine.

26. In pathological urine: it is due to pus , blood and bacteria . Degree of cloudiness depends on: pH and dissolved solids Turbidity: may be due to gross bacteriuria , Smoky appearance: is seen in hematuria . Thread-like cloudiness: is seen in sample full of mucus.

27. 3. Odor --- Normally urine -mild aromatic due to presence of urinoids.It may change to : a. FRUITY- Ketoacidosis , starvation b. MUSTY - Phenylketonuria c. FISHY – UTI with Proteus d. AMMONICAL - UTI with Escherichia coli e. FOUL- UTI f. SULFUROUS - Cystinuria

28. 4- Volume: Is important part of assessment for fluid balance and kidney functions. Adults produce from 750ml-2500ml / 24h, with the average of about 1.5L per person. For routine urine examination, a 10ml-12ml of sample is optimal for analysis.

29. I . POLYURIA : Urinary volume > 2500mL per day CAUSES : - Excessive intake of water ( polydipsia ). - Diabetes mellitus and diabetes insipidus . - Drugs with diuretic effect such as caffeine , alcohol and diuretics. -.chronic renal failure

30. Oligourea - urinary volume < 500 ml/day Causes- A. PRERENAL : loss of intravascular volume - haemorrhage - dehydration - severe vomiting -severe burns

31. B. POSTRENAL : -bilateral hydronephrosis -long standing obstruction of urinary tract. Obstruction may be due to clots , stones , strictures , tumour , sloughed tissues. C .RENAL PARENCHYMAL DISEASES

32. III . COMPLETE SUPRESSION : Of urine is called anuria ( < 150mL /day) CAUSES : - Retention of urine as in BPH and stricture in urethra. - Stone and tumours in kidney.

33. 5. pH - Normal reaction of urine is acidic with pH 4.6 to 7.6. CAUSES OF HIGHLY ACIDIC URINE : Protein-rich diet. UTI by E.coli Respiratory and metabolic acidosis Ingestion of acidic food.

34. CAUSES OF ALKALINE URINE: a. If specimen is allowed to stand at room temperature , it becomes alkaline. b. For the treatment of uric acid calculi c. UTI by urea splitting bacteria – proteus , pseudomonas

35. Methods of pH estimation--- 1.LITMUS PAPER TEST : 2. pH INDICATOR PAPER : 3. PH METER : 4. REAGENTS STRIP TEST:

36. Litmus paper test---

37. 6. Specific Gravity - - It depends on amount of solutes in solution. -It reflects the relative degree of concentration or dilution of a urine specimen. - It helps in evaluating the concentrating and diluting abilities of the kidneys - Urea( 20 %) ,Na Cl (25%), Sulphate , Phosphate – major contributors - SG ranges from 1.003-1.035. - Specific gravity of urine in normal adults with adequate fluid intake is 1.016 – 1.022.

38. Increase in specific gravity- Diabetes mellitus Nephrotic syndrome Fever Congestive heart failure Decrease in specific gravity- Diabetes insipidus Compulsive water drinking Isosthenuria - Specific gravity is fixed (1.010 )

39. Measurement of specific gravity- 1. Urinometer method- Based on principle of buoyancy 2. Refractometer method- Measures refractive index of dissolved solids 3. Reagent strip method- indirect method . 3 main ingredients : polyelectrolyte , indicator and a buffer.

40. Urinometer -

41. Urinometer is a hydrometer that is calibrated to measure the specific gravity of urine at a specific temperature, usually at 20 C. Based on principle of buoyancy so the urinometer will float higher in urine than in water, because urine is denser. Thus higher the specific gravity of a specimen, the higher the urinometer will float.

42. Specific gravity is affected by presence of dense molecules, protein and glucose. Subtract 0.003 from specific gravity after temperature correction for each 1 g/dl of protein and 0.004 for each 1g/dl of glucose . Temperature correction- For every 3 C below 20 C, subtract 0.001 from the reading and for every 3 C above 20 C, add 0.001.