Urinalysis

• ANALYZING URINE

  •References to the study of urine can be found in the drawings of cavemen and in Egyptian hieroglyphics, such as the Edwin Smith Surgical Papyrus.

  
  

  •Basic observations as color, turbidity, odor, volume, viscosity, and even sweetness (by noting that certain specimens attracted ants or tasted sweet)
• Hippocrates


  wrote a book on uroscopy in the 5th BCE
• Middle ages


  physicians concentrated their efforts very intensively on the art of uroscopy, receiving instruction in urine examination as part of their training
• 1140 CE


  -  color charts had been developed that described the significance of 20 different colors
• 1964 


  Frederick Dekkers discovered albuminuria by boiling urine
• Albumin


  Major protein in the blood
• Albuminuria


  presence of high levels of albumin
• 1627


  Thomas Bryant wrote a book on “pisse prophets” (also known as charlatans )
• 17th century


  the invention of the microscope led to the examination of urine sediment and the development by Thomas Addis of methods for quantitating urine sediments (Addis count -> cells in the urine)
• 1827


   Richard Bright included urinalysis as part of the doctor’s routine patient examination
• Urine


  95% water and 5% solutes (conc. of solutes influenced by: dietary intake, physical activity, body metabolism, endocrine functions

  • Primary organic component: Urea

  • Primary inorganic component: Chloride
• SPECIMEN COLLECTION:


  The procedure for collection should be explained properly to the patient since the type of urine collection and the method of collection depends on the type of test ordered by the physician.

  URINALYSIS ALSO HELPS IN:

  1. monitoring wellness
  2. determination and treatment of urinary tract infections
  3. detection and monitoring progress of treatment in metabolic diseases
  4. determining the effectiveness of an administered therapy as well as checking if the patients exhibited any therapy-related complications
• The accuracy of urine analysis results will largely depend on several factors such as:


  1. the collection method,
  2. container use,
  3. transportation and handling of specimens and
  4. the timeliness of the testing
• Urine container


  • Clear, clean, dry, leak-proof containers: Disposable containers
  • wide mouth to facilitate collections from female patients and a wide, flat bottom to prevent overturning
  • Individually packaged sterile containers with secure closures should be used for microbiologic urine studies
  • bags with adhesive for the collection of pediatric specimens and large containers for 24-hour specimens
  • 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
• LABELS IN THE SAMPLE CONTAINER:


  •patient’s name

  •identification number

  •date and time of collection

  •additional information such as the patient’s age

  •location and the healthcare provider’s name

  •Labels must be attached to the container
• Body


  Is where the labels should always be attached
• Boric Acid 


  Preserves urine, protein, and acids

  Preserve urine pH to 6.0
• Sodium Fluoride


  inhibits breakdown of glucose
• REJECTION


  The laboratory should reject improperly labeled and collected specimens, and appropriate personnel should be notified to collect a new specimen.

  1. Specimens in unlabeled containers

  2. Nonmatching labels and requisition forms

  3. Specimens contaminated with feces or toilet paper

  4. Containers with contaminated exteriors

  5. Specimens of insufficient quantity

  6. Specimens that have been improperly transported
• HANDLING

  The urine sample should be tested within 2 hours

  Delayed testing:  refrigerated or have an appropriate chemical preservative added
• PRESERVATION:


  The most routinely used method of preservation is refrigeration at 2°C to 8°C, which decreases bacterial growth and metabolism

  If the urine is to be cultured, it should be refrigerated during transit and kept refrigerated until cultured up to 24 hours.

  When a specimen must be transported over a long distance and refrigeration is impossible, chemical preservatives may be added.

  The ideal preservative should be bactericidal, inhibit urease, and preserve formed elements in the sediment.
• Required volume of urine for testing:

  10-15 mL

  Average: 12 mL
• Unpreserved urine changes will occur such as increase of:


  pH

  Bacteria

  Odor

  Nitrite
• Unpreserved urine

  Odor: Ammonia-like

  pH: 9 (more alkaline)
• Normal Urine pH

  8
• Types of urine samples: Random Specimen

  pH: 4.5-8.0
• Types of urine samples: Random Specimen


  •This is the most commonly received specimen because of its ease of collection and convenience for the patient.
• Types of urine samples: Random Specimen

  •may be collected at any time, but the actual time of voiding should be recorded on the container.
• Types of urine samples: Random Specimen


  •routine screening tests
• Types of urine samples: Random Specimen


  •may also show erroneous results resulting from dietary intake or physical activity just before collection
• Types of urine samples: First Morning Specimen

  pH: 5.0-6.0
• Types of urine samples: First Morning Specimen

  most concentrated sample
• Types of urine samples: First Morning Specimen


  •the ideal screening specimen
• Types of urine samples: First Morning Specimen


  •preventing false-negative pregnancy tests and evaluating orthostatic proteinuria
• Types of urine samples: First Morning Specimen

  •a concentrated specimen, thereby assuring the detection of chemicals and formed elements that may not be present in a dilute random specimen
• Types of urine samples: First Morning Specimen


  •The patient should be instructed to collect the specimen immediately on arising and to deliver it to the laboratory within 2 hours or keep it refrigerated.
• Types of urine samples: Glucose Tolerance Specimens


  sometimes collected to correspond with the blood samples drawn during a glucose tolerance test (GTT)