LAB 1: URINE ANALYSIS

• Hippocrates


  à wrote a book on uroscopy in 5th BCE
• 1140 CE à color charts had been developed that

  described the significance of 20 different colors
• 1964 à Frederick Dekkers discovered albuminuria

  by boiling urine
• 1627 à Thomas Bryant wrote a book on “pisse

  prophets”
• 17th century à invention of the microscope led to

  the examination of urine sediment and development

  by Thomas Addis of methods for quantitating urine

  sediments (Addis countà cells in the urine)
• 1827 à Richard Bright included urinalysis as part

  of the doctor’s routine patient examination.
• NEPHRON


  Major functional unit of the kidney
• NEPHRON

  Approximately 1 million per kidney
• NEPHRON


  Composed of glomerulus and renal

  tubules
• GLOMERULUS


  Coil of capillary vessels
• GLOMERULUS


  Filters 120 mL/min, or 1/5 of renal plasma
• Primary organic component:

  Urea
• Primary inorganic component:

  Chloride
• Aldosterone


  Adrenal Cortex
• Antidiuretic Hormone


  Posterior Pituitary Gland
• Erythropoietin


  Kidney
• Urine is an ultrafiltrate of plasma
• Reabsorption of water and filtered substances essential to body function converts approximately 170,000 mL of filtered

  plasma to the average daily urine output of 1200 mL
• Analyze within 1 hour of voiding
• Increased: Nitrite

  Glucose
• Increased: pH

  Ketones
• Increased: Turbidity

  Bilirubin
• Urine is the most frequently analyzed non-blood

  body fluid
• Urine is considered a biohazard substance that

  requires the observance of Standard precautions
• Disposable, non-sterile, plastic containers are most

  commonly used (capacity: 50 mL)
• Urine from infants - Pliable polyethylene bags with

  adhesive
• 24-hour urine collection - Large, wide-mouthed

  plastic containers are used
• Urine for bacterial culture – sterile plastic

  containers
• most routinely used method of preservation is

  REFRIGERATION AT 2°C TO 8°C
• Preservation decreases bacterial growth and

  metabolism
• CLARITY


  ➢ Normal urine: clear

  ➢ Any of the urinary sediments (cells, casts,

  crystals or bacteria) may make urine

  cloudy
• COLOR


  ➢ Normal urine: pale yellow (straw) to

  yellow color

  ➢ Urochrome - yellow color of urine
• Urochrome 


  Responsible for the normal color of urine
• Urochrome: Named by Thudichum in 1864
• urochrome is dependent on the body’s metabolic state, with increased amounts produced in thyroid conditions and fasting
• Uroerythrin – pink pigment, indicator that

  the specimen is refrigerated (binds to

  amorphous urates leading to its

  precipitation)
• Urobilin – oxidation product of urobilinogen,

  Imparts Orange brown color of urine that is

  not fresh
• Amber – dehydration from fever and burns
• Bilirubin

  ❖ Yellow foam appears when the

  specimen is shaken
• Urobilinogen

  ❖ Due to photo-oxidation of

  urobilinogen to urobilin