1. Urine Testing

2. Testing Urine
Unit 18:11

3. Urinalysis
Examination of urine
Physical
Chemical
Microscopic

4. Physical Testing of Urine
Observing color, transparency & specific gravity

5. Color Normal: shade of yellow Pale: dilute
Dark yellow, orange: concentrated
Cloudy red: hematuria
Clear-red: hemoglobin
Yellow or beer-brown: bilirubin (bilirubinuria)

6. Transparency
Normal: clear
Cloudy: pus, mucus
Milky: fats

7. Specific Gravity Normal: 1.005 to 1.030
Increased: dehydration, diabetes mellitus
Decreased: kidney disease, diuretic, increased fluid intake

8. Odor Normal: Faintly aromatic Ammonia: old sample Foul: infection
Sweet: DM, ketones

9. Chemical Testing pH Protein Glucose Ketones Bilirubin Urobilinogen
Blood

10. Microscopic Testing Examine formed elements in urine Cells Casts
Crystals
Amorphous debris

11. Which urine is best? Fresh, warm urine Within 1 hour of collection
Maybe refrigerated if needed

12. Precautions Must use standard precautions
Gloves, possibly mask, eyewear
Discard urine in a toilet
Dispose of specimen in infectious waste bag

13. Using Reagent Strips to Test Urine
Unit 18:12

14. Reagent Strips
Firm plastic strip with chemical reactants attached to the strip
Color change indicates presence of substance & amount of substance

15. Storage Sensitive to light, heat, moisture
Store in dry, cool, dark area
Keep bottle closed

16. Precautions Don’t touch chemical reactant pads
May lead to inaccurate results or injure the skin

17. pH Measure of acidity or alkalinity of urine Normal: 5.5 to 8.0
Affected by:
Diet
Medications
Kidney disease
Starvation

18. Protein
Normal: none
Proteinuria may indicate kidney disease

19. Glucose
Normal: none
May indicate Diabetes mellitus

20. Ketones End product of fat metabolism Normal = none May indicate:
Diabetes mellitus
Fasting, dieting
High fat diet

21. Blood Normal = none May indicate: Injury Infection Menstruation
Kidney disease

22. Bilirubin Break down product of hemoglobin Normal = none May indicate:
Liver disease

23. Urobilinogen Bilirubin converted by intestinal bacteria
Normal: small amounts
May indicate:
Heart, spleen, liver or hemolytic disease

24. Spectrophotometers Automated strip analyzer
More accurate than human eye

25. Refrigerated samples
Must be returned to room temperature

26. Time
Follow exact time for each chemical reaction

27. Measuring Specific Gravity
Unit 18:13

28. Specific Gravity
Density of a substance compared to the density of water
Normal: to 1.030

29. Urinometer
Urine in a cylinder and calibrated float is placed in urine with a spinning motion
Urine collects at curved line, meniscus
Read of lower part of meniscus

30. Refractometer
One drop of urine placed on device & look through an eyepiece
Calibrate with water

31. Preparing Urine for Microscopic Examination
Unit 18:4

32. Urine Sediment
Solid materials suspended in urine

33. What urine? Fresh, early morning first voided specimen preferable
Examine immediately
Some elements disintegrate

34. Centrifuge Spin ~10-15 cc of urine
Solid materials settle at the bottom

35. Preparation Clear urine on top is poured off
Leave behind 1 cc in bottom

36. Examine immediately
Drying occurs quickly & can distort substances

37. lpf and hpf Low power field and high power field
Indicate amount seen in a field

38. RBCs Normal = none May indicate: Kidney disease
Bleeding in urinary tract
Menstruation

39. WBCs
Normal = small numbers
May indicate:
infection

40. Bacteria
Normal: none to small amount
Large amount indicates infection

41. Other infectious agents
Fungi, yeasts
Parasites

42. Casts
Formed in kidney tubules during kidney damage
Normal = none

43. Crystals
Dependent on urine pH