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Biomedical Diagnostics 1. Ch.1 related data. INTEGRATING LAB DATA INTO TCM PRACTICE. Healthcare: Complex Driven by technology Tests help formulate strategy Recognize Red Flags Prepare for evidence based practice. HIPPA AND LAB REPORTS. Covers sharing of lab reports DNA tests?
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Biomedical Diagnostics 1 Ch.1 related data
INTEGRATING LAB DATAINTO TCM PRACTICE • Healthcare: • Complex • Driven by technology • Tests help formulate strategy • Recognize Red Flags • Prepare for evidence based practice
HIPPA AND LAB REPORTS • Covers sharing of lab reports • DNA tests? • Web based tests? • Point of Care (POC) tests • CLIA (Clinical laboratory Improvement Act 1988) • CLIA Waived
USING LABORATORY DATA • CLINICIAN’S TASK- • Make reasoned decisions- • In certain situations diagnostic tests are mandated
Categories of testing • Screening • Diagnostic • Patient management
SCREENING • Helps in identifying risk factors- • In early detection of “occult” diseases- • Benefits, Costs and Risks must be considered
CRITERIA FOR SCREENING POPULATION: NATURE OF THE DISEASE: TEST CHARACTERISTICS: • GOOD SENSITIVITY & SPECIFICITY • LOW COST AND RISK • Home Test Kits- Txt Book Table 1-4 page 13
Page 5 Bell Curve and Standard Deviation (SD)
REFERENCE RANGE Method and laboratory specific Reflects results found in 95% of a healthy population Means 5% will have ‘false positive’ results Therefore ‘borderline’ results must be viewed critically
Main Criteria (page 7-9) • Sensitivity • & • Specificity
Sensitivity- • Sensitivity= TP/(TP +FN) • Specificity- • Specificity= TN/(TN + FP) • TN= True Negatives • TP= True Positives • FP= False Positives
Sensitivity & Specificity • (SnNouts and SpPins) • Definition • Sensitivity refers to the proportion of people: with disease who have a positive test result. • Specificity refers to the proportion of people: without disease who have a negative test result.
SpPins and SnNouts • SpPin is a mnemonic applied to the finding that when a sign, test or symptom has a • high Specificity, a • Positive result rules in (SPin) the diagnosis.
SpPins and SnNouts • SnNout is a mnemonic applied to the finding that when a sign, test or symptom has a • high Sensitivity, a • Negative result rules out (SNout) the diagnosis.
EVIDENCE BASED MEDICINE (page 19) • FOR SOUND METHODOLOGY • CRITICAL APPRAISAL OF RESEARCH DATA • PUBLISH ACCURATE & CLINICALLY USEFUL SUMMARIES OF EVIDENCE
POINT OF CARE (POC) TESTS • URINALYSIS • ‘SCREENING TESTS’(page 2) • SIMPLE BLOOD TESTS • ?HOME TEST KITS • DAT: Direct Access Testing
Collection Tubes • Additives • Preservatives • Anticoagulants • Gel separation tubes • Serum tubes • Plasma tubes • Trace element-free tubes • Pediatric tubes (3 mL)
B. BLOOD COLLECTION • Site: Arteries, Veins, Capillaries • Component Types used for testing: Whole Blood Plasma Serum
PLASMA • “... the river in which the blood cells travel.” • Contains: • Water • Nutrients • (sugars, amino acids, fats, electrolytes, minerals, etc.) • 3. Waste products (CO2, lactic acid, urea, etc.) • 4. Antibodies (immunoglobulins) • 5. Clotting proteins (called clotting factors) • 6. Hormones • 7. Complement Proteins • (inflammation, immune response) • 8.Transport Proteins (albumin) • 60% Total Blood Volume • Plasma = serum + clotting components
Lipemia: Can cause factitious Hyponatremia, Hypokalemia, Hyperchloremia Turbidity -- Due to lipid particles; causes light to scatter...interferes with photometry Partitioning Error -- Analyte can enter lipid…making it inaccessible for chemical reaction Electrolyte Exclusion Effect -- Triglycerides > 1500mg/dL (milky serum): Fat replaces serum water, which alters distribution & conc. of electrolytes
Some Lab Methods • Microbiology- Gram staining- first stain with crystal violet- wash- then second stain with Grams iodine-rinse after decolorizing with alcohol-counter stain with safranin and rinse and dry; • Gram negative stain pink • Gram positive stain purple
URINE • & • RENAL • TESTS • Discuss: • Components • of Urine • Collection • of Urine
A. Urine Components: Color: Yellow, Amber, Red,Orange Clarity: Clear, Cloudy Microscopy: Normal/Abnormal cells, crystals, Chemistry Testing: Electrolytes Kidney function testing Glucose Heavy metals Drug Screens Protein Uric Acid Calcium … & more
B. Collection of Urine: Random or timed • Sterile plastic container • With/without preservatives • “Clean Catch” • Cleanse skin • Collect midstream sample • Catheter • Suprapubic • Children 2 L collection jug
Timing of Urine Collection: • 1.Random Urine Collection • Examples: • First morning void: • (best for drug analysis) • 2- or 3-hour post-prandial: (glucosuria) • Afternoon: • (urobilinogen) • Anytime: urinalysis, • urine pregnancy
2.Timed Urine Collection: • Specified intervals (2-, 12-, 24-hour) • Special instructions - diet, drugs, collection technique, preservatives • How to collect? • 1) empty bladder & discard (“first void” urine) • 2) Record time and begin urine collection • 3) Store container @ 4C between collections (preservative may be required) • 4) Record time and volume at the end of collection interval • 24-hour • Why? diurnal variation of analyte
Crystals Seen in Urine • Normal: calcium oxalate, triple phosphate crystals and amorphous phosphates • Very uncommon crystals include: • cystine crystals in urine of neonates with congenital cystinuria or severe liver disease, • tyrosine crystals with congenital tyrosinosis or marked liver impairment, or • leucine crystals in patients with severe liver disease or with maple syrup urine disease
little envelopes or tetrahedrons – Oxalate (common) • stop signs – Cystine (rare) • rectangles – triple phosphates
‘Renal’ Tests • Creatinine Clearance, page 90 • GFR, (198) • CMP, • BUN, (63) • Creatinine, (89)
Serum assessment of Renal function • BUN- 8-25 mg/dL • Creatinine- 0.6-1.5 mg/dL • >1.5 = 50% nephron loss • >4.8 = 75% loss • ~10 = 90% loss (ESRD)
BUN:Creatinine ratio • Normal: 10:1 ~20:1. • An increased ratio may be due to a condition that causes a decrease in the flow of blood to the kidneys: • such as congestive heart failure or dehydration, increased protein, from gastrointestinal bleeding, or increased protein in the diet. • The ratio may be decreased with liver disease (due to decrease in the formation of urea) and malnutrition.
?Uric Acid (213) • Produced by the breakdown of purines • Purines are chemicals that come from nucleic acids (DNA)- source:-cells and food • Most uric acid is removed by the kidneys and disposed of in the urine • Gouty arthritis, also known as gout, is a condition caused by the deposition and accumulation of needle-like uric acid crystals in the fluid and tissues of one or more joints. • This causes inflammation, swelling, and severe pain in the joint.
Uric Acid • Purine metabolism • ‘Gout’ • Diuretics- thiazides/lasix • Pre eclampsia/eclampsia • Excessive cell destruction –CCT • Prolonged fasting • M- 3.6-8.5 mg/dL ; W- 2.3-6.6 mg/dL
FOODS RICH IN PURINES Note!: Purines are part of nucleic acid metabolism Destruction of DNA as it happens in cancer chemotherapy can result in elevated serum uric acid levels • ANCHOVIES • ASPARAGUS • KIDNEYS • LIVER • LENTILS • SARDINES • SPINACH • SWEETBREADS
Do NOT Confuse! List • Creatine- consumption of high glycemic carbohydrates in conjunction with creatine increases creatine muscle stores and performance. (Cell-TechⓇ-creatine-carbohydrate-alpha lipoic acid supplement ) • Creatinine- Creatinine is a break-down product of creatine phosphate in muscle. Creatinine clearence measures kidney GFR • Creatine Kinase (CK) • Creatine phosphokinase (CK)- Creatine kinase (CK), also known as phosphocreatine kinase or creatine phosphokinase (CPK) is an enzyme expressed by various tissue types. It catalyses the conversion of creatine to phosphocreatine, consuming adenosine triphosphate (ATP) and generating adenosine diphosphate (ADP). • Clinically, creatine kinase is assayed in blood tests as a marker of myocardial infarction (heart attack), rhabdomyolysis (severe muscle breakdown), muscular dystrophy and in acute renal failure.
BASIC-information about the current status of kidneys, blood sugar, and electrolyte and acid/base balance. Glucose Calcium Sodium Potassium CO2 (carbon dioxide, bicarbonate) Chloride BUN (blood urea nitrogen) Creatinine COMPREHENSIVE Glucose Calcium Sodium Potassium CO2 (carbon dioxide, bicarbonate) Chloride Albumin Total Protein BUN (blood urea nitrogen) Creatinine ALP (alkaline phosphatase) ALT (alanine amino transferase, SGPT) AST (aspartate amino transferase, SGOT) Bilirubin Metabolic Panels
ACID BASE BALANCE page 392-393 • Renal Failure-462 • Urinalysis in disease states-479