Physical examination

• Routine Urinalysis


  A routine screening test which is usually done as a part of a physical examination, during preoperative testing, and upon hospital admission

  
• First Voided Urine


  Also referred to as a first morning specimen, the most concentrated and often the best specimen for analysis
• 3 Phases of Routine Urinalysis

  • Physical
  • Chemical
  • Microscopic
• Physical Examination of Urine

  • Transparency
  • Appearance and Color
  • Urochrome
  • Uroerythrin
  • Urobilin
• Amorphous Phosphates and Carbonates cause white cloudiness in alkaline pH
• Amorphous Urates cause a whitish or pink cloud in acidic urine due to presence of uroerythrin
• About 200 WBC/mm3 or 500 RBC/mm3 produce turbidity
• Bacteria cause a uniformly dispersed cloudiness, which does not settle and cannot be filtered out
• Prostatic Fluid and Spermatozoa can cause turbidity
• Urine Transparency Interpretation

  • Clear
  • Transparent
  • Hazy
  • Cloudy
  • Turbid
  • Milky
• Urine Color


  Corresponds to the specific gravity of the urine, diluted urine is almost colorless, concentrated urine is dark to yellow to amber
• Urochrome


  Responsible for the yellow color of urine
• Uroerythrin


  Responsible for the white or pink color of urine when stand, attaches to urates, color is more evident when refrigerated
• Urobilin


  Imparts an orange to brown color to urine, product of the oxidation of urobilinogen
• Urine Specific Gravity


  The density of a solution compared to the density of a similar volume of distilled water (1.000) at a similar temperature, reference range is 1.002 to 1.035, average range is 1.015 to 1.030
• Substances contributing to Urine Specific Gravity

  • Chloride
  • Urea
  • Phosphate
  • Protein
  • Sugar
• Refractometer


  Determines the concentration of dissolved particles by measuring the refractive index, small volume of specimen is needed, temperature correction is not necessary for 15°C to 38°C, only glucose and protein have corrections
• Refractometer Calibration

  • Distilled Water (1.000)
  • 5% NaCl (1.022 ± 0.001)
  • 9% Sucrose (1.034 ± 0.001)
• Refractometer Computation

  1. Initial Refractometer Reading

  2. Subtract 0.003 for each gram of protein

  3. Subtract 0.004 for each gram of glucose

  4. Final Refractometer Reading