MACROSCOPIC AND CHEMICAL EXAMINATION OF URINE

• 2 responsibilities Medtech have when it

  comes to urine collection

  1. Instruct the patient on how to properly collect his or her urine
  2. Receive our specimen (wear PPE)
• SPECIMEN COLLECTION

  Clean, dry, leak-proof containers, screw top lids,

  wide mouth, clear. (Disposable containers are recommended)
• REASONS FOR REJECTING URINE

  • Specimens in unlabeled containers
  • Nonmatching labels and requisition forms
  • Specimens contaminated with feces or toilet paper
  • Containers with contaminated exteriors
  • Specimens of insufficient quantity
  • Specimens that have been improperly transported
• SPECIMEN INTEGRITY

  • Specimens should be delivered to the laboratory promptly and tested withing 2 hours
  • A specimen that cannot be delivered and tested within 2 hours should be refrigerated or have an appropriate chemical preservative added
• PHYSICAL EXAMINATION OF URINE

  There are 4 tests in the physical examination of urine (color, clarity, volume, and odor of urine).
• NORMAL URINE COLOR

  Pale yellow, yellow, dark yellow, and amber
• Dark yellow and amber can be interpreted as normal urine color or abnormal urine color.
• Dark Yellow or Amber

  presence of the abnormal pigment bilirubin
• Yellow-orange

  administration of phenazopyridine (pyridium) or azogantrisin compounds to persons with urinary tract infections
• Red

  Presence of blood
• Presence of blood in urine

  Commonly seen in menstruating patients [medtech should take note of this]

  • For pathologic why there would be blood in the urine, it can be physical injury itself of the urethra or urinary tract, or there could be infections
• Brown Urine containing Blood

  glomerular bleeding
• Brown or black

  melanin or homogentisic acid, levodopa, methyldopa, phenol derivatives, and metronidazole (Flagyl)
• Blue/Green

  bacterial infections, including urinary tract infection by Pseudomonas species and intestinal tract infections resulting in increased urinary indican
• Physical Examination of urine

  Clarity or transparency of urine
• Urine Clarity

  Clear

  Hazy

  Cloudy

  Turbid

  Milky
• Clear


  No visibile particulates, transparent
• Hazy - Few particulates, print easily seen through urine.
• Cloudy - Many visible particulates, print not clearly seen through urine.
• Turbid


  print cannot be seen through urine
• Milky


  may precipitate of be clotted
• COLOR AND CLARITY PROCEDURE

  • Use a well-mixed specimen

  • View through a clear container

  • View against white background

  • Maintain adequate room lighting

  • Evaluate a consistent volume of specimen

  • Determine color and clarity
• Odor of Urine

  Freshly voided urine: faint aromatic odor
• Odor of Urine

  Aromatic

  Foul, ammonia-like

  Fruity, sweet

  Maple Syrup

  Mousy

  Rancid

  Sweaty Feet

  Cabbage

  Bleach
• Aromatic

  Normal
• Foul, ammonia-like

  Bacterial decomposition, urinary tract infection
• Fruity, Sweet


  Ketones (diabetes mellitus starvation, vomiting)
• Maple Syrup

  Maple syrup urine disease
• Mousy

  Phenylketonura
• Rancid


  Tyrosinemia
• Sweaty Feet

  Isovalerie acidemia
• Cabbage

  Methionine malabsorption
• Bleach


  Contamination
• Reagent Strips

  • Sometimes called “dip strips”

  • Consist of chemical- impregnated absorbent pads attached to a plastic strip

  • A color-producing chemical reaction takes place when the absorbent pad comes in contact with urine

  The reactions are interpreted by comparing the color produced on the pad with a chart supplied by the manufacturer
• Care of Reagent Strips

  • Store with desiccant in an opaque, tightly closed container

  • Store below 30C [room temperature]; do not freeze

  • Do not expose to volatile fumes

  • Do not use past the expiration date

  • Do not use if chemical pads become discolored • Remove strips immediately prior to use
• Procedure of Chemical Examination of Urine

  1. Mix specimen well

  2. Let refrigerated specimens warm to room temperature before testing

  3. Dip the strip completely, but briefly, into specimen

  4. Remove excess urine by withdrawing the strip against the rim of the container and by blotting the edge of the strip

  5. Compare reaction colors with the manufacturer's chart under a good light source at the specified time

  6. Perform backup tests when indicated
• Chemical Examination of Urine

  • Be alert for the presence of interfering substances
  • Understand the principles and significance of the test, read package inserts
  • Relate chemical findings to each other and to the physical and microscopic urinalysis results
• Quality Control of Reagent Strip

  • Test open bottles of reagent strips with known positive and negative controls every 24 hours

  • Resolve control results that are out of range by further testing

  • Test reagents used in backup tests with positive and negative controls

  • Perform positive and negative controls on new reagents and newly opened bottles of reagent strips

  • Record all control results and reagent lot numbers
• pH


  • Aid in determining the existence of systemic acid- base disorders of metabolic or respiratory origin and in the management of urinary conditions that require the urine to be maintained a specific pH
• pH

  • First morning specimen [most concentrated]– slightly acidic pH of 5.0-6.0

  • Normal random samples [wide range of value]– 4.5 to 8.0

  • Reagents – methyl red, bromthymol blue