MLSP

• Reasons for urinalysis


  • Diagnosis
  • Screening asymptomatic population for undetected disorders
  • Monitoring of progress of disease and effectiveness of therapy
• Urine formation


  Ultra filtrate of plasma, formed at kidneys, daily output of 1.2-1.5L
• Terms related to urine output

  • NDO (1.2-1.5L, 600-2000ml also normal)
  • Oliguria (DUO: 400ml/Day (Adults), Excessive water loss)
  • Anuria (Cessation of urine flow, severe kidney damage)
  • Nocturia (Increased excretion of urine at night)
  • Polyuria (IUO: >2.5L/Day (Adults))
• Urine composition


  95% water and 5% solutes
• Organic solutes in 24hr urine specimen

  • Urea (25-35g, 60-90% nitrogenous matters)
  • Creatinine (1.5g, creatine muscle metabolism)
  • Uric acid (0.4-1g, common component of kidney stones)
  • Hippuric acid (0.7g, benzoic acid)
  • Others (2.9g)
• Urine collection container requirements

  • Clean and dry (sterile)
  • Leak proof
  • Screw top lids
  • Wide mouth
  • Clear material
  • Recommended capacity: 50ml
  • Labelled (attached to container, not lid)
• Types of urine specimens

  • Random (routine screening)
  • First morning (routine screening, pregnancy test, orthostatic protein)
  • Fasting (diabetic screening/monitoring)
  • 24hr timed (quantitative chemical tests)
  • Catheterized (bacterial culture)
  • Midstream clean-catch (routine screening, bacterial culture)
  • Suprapubic aspiration (bladder urine for bacterial culture, cytology)
• Most common urine specimen is random, most preferred is first morning (more concentrated)
• 24hr urine specimen


  Quantitative measurements, larger container with preservative, stored at 2-8 Celsius
• Suprapubic aspiration


  Most used on pediatrics, needle introduced from abdomen into bladder
• Catheterized specimen


  Passing of hollow tube through urethra and bladder
• Midstream clean-catch


  Alternative to catheterized, less traumatic, less contamination
• Urine drug sample collection requirements

  • Witnessed or unwitnessed
  • If witnessed, same-gender collector will observe
  • 30-45ml of urine collected
  • Temperature, pH, color, specific gravity tested immediately
  • Ideal temperature 32.5-37.7C
  • pH greater than 9 suggests adulteration
  • Specific gravity less than 1.005 suggests dilution
• Urine preservatives


  • Refrigeration (2-8C, no interference with chemical tests, raises specific gravity, precipitates urates and phosphates)
  • Toluene (no interference with routine tests, floats on surface and clings to pipettes)
  • Sodium fluoride (ideal for drug testing, inhibits reagent strip tests)
  • Formalin (preserves sediments, interferes with chemical tests)
  • Phenol (no interference with routine tests, odor change)
• Purposes of stool examination

  • Evaluation of gastrointestinal disorders
  • Evaluation for presence of parasites and eggs
  • Fat and urobilinogen content
  • Culture to detect pathogenic bacteria and viruses
  • Occult (hidden) blood using guaiac test
  • Fecal occult blood test (FOBT)
• FOBT requirements


  • Meat-free diet for 3 days prior
  • Collection of separate specimens for 3 consecutive days
• Purposes of semen analysis

  • Evaluate fertility and post-vasectomy procedures
  • Abstain 3-5 days before collecting
  • Collected at lab in warm sterile container, not in condom
  • If collected at home, kept warm and delivered to lab within 1 hour
  • Record time of collection and receipt
• Normal values for semen analysis

  • Volume (2-5mL)
  • Viscosity (pours in droplets)
  • pH (7.2-8.0)
  • Sperm concentration (>20 million/mL)
  • Sperm count (>40 million/mL)
  • Motility (>50% within 1 hr)
  • Quality (>2.0)
  • Morphology (>14% normal forms, strict criteria; >30% normal forms, routine criteria)
  • Round cells (<1.0 million/mL)
• Cerebrospinal fluid (CSF)


  Surrounds brain and spinal cord, removes metabolic wastes, routinely collected between 3rd, 4th, 5th lumbar vertebrae
• Routine tests performed on CSF

  • Cell counts
  • Chemistry tests (chloride, glucose, total protein)
• CSF collection tubes


  • Chemistry and immunology
  • Microbiology
  • Hematology (cell count)
  • Hematology
• CSF should be kept at room temperature, delivered to lab stat, and analyzed immediately
• CSF fluid appearance and significance

  • Crystal clear (normal)
  • Hazy, turbid, milky, cloudy (WBCs, microorganisms, protein, meningitis)
  • Oily (radiographic contrast media)
  • Bloody (RBCs, hemorrhage, traumatic tap)
  • Clotted (protein, clotting factors, disorders affecting blood-brain barrier)
  • Pellicle (protein, clotting factors, disorders affecting blood-brain barrier)
  • Xanthochromic (hemoglobin, old hemorrhage, lysed cells from traumatic tap, RBC degradation, elevated serum bilirubin, increased serum disorders affecting blood-brain barrier)
  • Tubular (meningitis)
  • Melanin (meningeal melanosarcoma)
• Synovial fluid


  Clear, pale-yellow, viscous fluid that lubricates movable joints, normally occurs in small amounts but increases with inflammation
• Reasons for synovial fluid collection


  • Identification or differentiation of arthritis, gout, and other inflammatory conditions
• Synovial fluid collection tubes

  • EDTA or heparin tube (cell count, crystal identification, smear prep)
  • Sterile tube (culture and sensitivity)
  • Nonadditive tube (macroscopic appearance, chemistry, immunology, clot formation)
• Normal synovial fluid parameters


  • Volume (<3.5mL)
  • Color (colorless to pale-yellow)
  • Clarity (clear)
  • Viscosity (able to form a string 4-6cm long)
  • Leukocyte count (<200 cells/uL)
  • Crystals (none present)
  • Glucose: plasma difference (<10 mg/dL lower than blood glucose)
  • Total protein (<3 g/dL)
• Serous fluid


  Pale-yellow, watery, serum-like fluid found between double-layered membranes enclosing pleural, pericardial, and peritoneal cavities, lubricates membranes
• Serous fluid collection


  EDTA tubes for cell counts or smears, heparin or sodium fluoride tubes for chemistry, nonanticoagulant tubes for biochemical tests, sterile heparinized tubes for cultures
• Types of serous fluid

  • Pleural fluid (pleural space/cavity surrounding lungs)
  • Peritoneal fluid (abdominal cavity)
  • Pericardial fluid (pericardial cavity surrounding heart)
• Amniotic fluid


  Clear, almost colorless to pale-yellow fluid that fills the amniotic sac, collected after 15 weeks gestation
• Purposes of amniotic fluid analysis

  • Detect genetic disorders, hemolytic disease
  • Detect and assess fetal lung maturity
  • Estimate gestational age
• Amniotic fluid alpha-fetoprotein (AFP)

  Test for neural tube defects, fetal lung maturity assessed by lecithin-to-sphingomyelin (L/S) ratio
• Amniotic fluid collection


  Collected in sterile container, protected from light, delivered to lab ASAP, specimens for chromosome analysis kept at room temp, some chemical tests kept on ice
• Gastric fluid analysis


  Analyzes for abnormal substances and gastric concentration to evaluate stomach acid production, basal gastric analysis involves tube passed through mouth/nose into stomach after fasting, gastric stimulants like histamine or pentagastrin used
• Phlebotomist's role in gastric fluid analysis


  Label specimens, draw blood for serum gastrin
• Sputum sample


  Mucus or phlegm ejected from respiratory system, used to diagnose or monitor lower respiratory tract infections like tuberculosis
• Sputum sample requirements


  • Preferred specimen is first morning, at least 1 hour after meal, 3-5mL typically required, transported at room temp, requires immediate processing
• Buccal swabs


  Less invasive, painless alternative for blood collection for DNA analysis, strict chain of custody protocol for legal purposes
• Saliva


  Fluids secreted by mouth glands, used to monitor hormone levels and detect alcohol/drug abuse