Primary amyloidosis Ppts latest 50 Published articles

Primary amyloidosis: Primary amyloidosis is a disorder in which abnormal proteins build up in tissues and organs. Clumps of the abnormal proteins are called amyloid deposits.

Primary amyloidosis can lead to conditions that include:
    Carpal tunnel syndrome
    Heart muscle damage (cardiomyopathy) leading to congestive heart failure
    Intestinal malabsorption
    Liver enlargement
    Kidney failure
    Nephrotic syndrome
    Neuropathy (nerves that do not work properly)
    Orthostatic hypotension (abnormal drop in blood pressure with standing)

Primary  AL Amyloidosis
by Matthew  Volk
http://www.med.unc.edu/medicine/web/12.1.08%20Volk.%20Amyloid,%20LCDD.ppt

Cardiac  Amyloidosis
by Ann Isaksen
https://medicine.med.unc.edu/education/internal-medicine-residency-program/files/ppt/11.10.09%20Isaksen%20cardiac%20amyloid.ppt

Primary  Amyloidosis  Case Presentation & Discussion
By Warren  Brenner
http://hematology.wustl.edu/conferences/presentations/Brenner20031017.ppt

Immune Disorders:  HLA and Disease Associations and Amyloidosis
by Nancy L. Jones, M.D.
http://cmspath.edu/rfc/lectures11-12/jones/hla/jones-hla_and_amyloidosis.ppt

Protein  Structure Determination, Protein Folding, Molecular Chaperones, Prions Alzyheimer’s
http://www.uh.edu/sibs/faculty/glegge/lecture_18.ppt

Computational  Method for Predicting Amyloidogenic Sequences
by Bill Welsh
http://dimacs.rutgers.edu/Workshops/Neurodegenerative/slides/welsh.ppt

Alphabet  Soup and Interstitial Lung Disease
by Leslie  Scheunemann
http://www.med.unc.edu/medicine/web/3.26.08%20ILD%20Scheunemann.ppt

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Coagulation Testing

Coagulation Testing
By:Diane Jette
BioMedica Diagnostics Inc.

Composition of Blood
* Formed Elements
o Erythrocytes (RBC)
o Leukocytes (WBC)
+ Neutrophils
+ Eosinophils
+ Basophils
+ Lymphocytes
+ Monocytes
o Thrombocytes (Platelets)
* Plasma
o 92% water
o 7 to 9 % of solutes are proteins
+ 55 to 60% Albumin, 15% Globulins, 4% Fibrinogen
o Non-protein nitrogen substance, Enzymes, Antibodies, Electrolytes, etc.
o Serum: No fibrinogen or Factors II, V and VIII

Hemostasis is the arrest of bleeding from an injured blood vessel
* Vasoconstriction and compression of injured vessels
* Platelets adhere to the site of injury and form a platelet plug
* Platelets release factors to augment vasoconstriction and initial vessel wall repair
* Platelets provide surface membrane sites and components for the formation of enzyme/cofactor complexes in blood coagulation reactions

Coagulation Reactions Lead to the Formation of a Blood Clot
* Two pathways: Intrinsic and Extrinsic - Coagulation Cascade
* Formation of a prothrombin activator - complex of Factor Xa, Factor Va and procoagulant phospholipid on surface of platelets.
* Prothrombin activator cleaves prothrombin into two fragments to give Thrombin.
* Thrombin cleaves small peptides from fibrinogen to form fibrin monomers that polymerize.
* Thrombin activates Factor XIII to cross-link the fibrin to form an insoluble clot.

Coagulation Cascade
* Intrinsic Pathway: (APTT)
o Factors VIII, IX, XI, and XII.
o Activated on surface of exposed endothelium.
o Complexes form on platelet phospholipids.
* Extrinsic Pathway: (PT)
o Factors IV, V, VII, X
o Activated by Tissue phospholipids (Tissue Factor or Tissue thromboplastin) released into blood as a result of tissue damage.
* Common Pathway (Thrombin Time)
o Factors I and II
o Leads to the formation of Fibrin Clot
o Thrombin time does not measure deficiencies in Intrinsic or Extrinsic pathway

The Role of Calcium
* Ca ions are needed for most of the reactions in the Coagulation Cascade
* Ca-chelating agents are used in vitro as anticoagulants (Citrate, EDTA, Oxalate)
* When Coagulation Factors are synthesized without Vitamin K they cannot bind Ca and lose enzymatic function

Regulatory Mechanisms
* Inhibition of Factor Activity
o Plasma protease inhibitors: anti-thrombin III (ATIII), *2-macroglobulin, *1 - antiprotease
o Heparin converts ATIII from a slow acting inhibitor to an instantaneous inhibitor of Thrombin, Factor Xa and Factor IXa
o Protein C and Protein S are serine proteases that cleave Factors VIII and Factor Va rendering them inactive

Fibrolysis
* Fibrin clot is degraded by protolytic enzymes and fragments dissolved in blood
* Process is catalyzed by Plasmin
* Plasminogen is converted to Plasmin
* Activation by tissue plasminogen activator (tPA) and urokinase
* Fibron degrades into large fragments X and Y then smaller fragments D and E

Regulation of Fibrolysis
* Plasminogen activator inhibitors (PAIs) and plasmin inhibitors slow the fibrolysis process
* tPA and urokinase have short half-lives and are rapidly cleared through the liver
* Unbound plasmin is instantaneously neutralized by 2-antiplasmin

Hereditary Coagulation Disorders
* Hemophilia A
o Factor VIII deficiency
o 80% of all Hemophilia cases
* Hemophilia B
o Factor IX deficiency
* Prolonged ATPP
o Recovered by dilution 1:1 with normal plasma
* Normal PT and Normal Bleeding Time
* Factor XI Deficiency
o 5 to 9% of European Jews
* 2-antiplasmin Deficiency

Acquired Coagulation Disorders
* Liver Disease
o Impaired clotting Factor synthesis
o Increased fibronolysis
o Thrombocytopenia
* Desseminated Intravascular Coagulation (DIC)
o Something enters the blood that activates factors
o Complication of obstetrics, infection, malignancy, shock, severe brain trauma
o Elevated PT, APTT, D-Dimer and other fibron degradation products

Circulating Anticoagulants
* Antibodies that neutralize clotting factor activity
* Factor VIII Anticoagulants
o Antibody
o Same profile as Hemophilia A
o Clotting time not restored by mixing with normal plasma
o Life-threatening condition

Lupus Anticoagulants
* Antibodies to phospholipid binding sites on clotting factors
* Prevent factors from accumulating on phospholipid surfaces
* Elevated APTT clotting times not corrected with mixing with normal plasma
* PT normal or slightly elevated.
* Non-specific depression of clotting factor activities (Factors VIII, IX, XI, XII)
* Test sensitivity increased by using diluted reagent
o Dilute ATPP reagent, Russell’s viper venom time, Kaolin time
o Clotting times corrected with the addition of phospholipids

Oral Anticoagulant Therapy
* Coumadin or Warfarin
* Inhibitor of Vitamin K dependant Factor synthesis
* Oral anticoagulant
* Dose regulated by therapeutic effect
* PT assay to measure INR
* INR range established for optimum therapeutic effect (typically 2.0 to 3.0)

Prothrombin Time: PT
* PT reagent contains Calcium ions and Thromboplastin from brain tissue (Rabbit).
* Thromboplastin (Tissue Factor) protein-lipid complex found in tissues outside blood vessels.
* Measures the function of the Extrinsic Pathway.
* Sensitive to Factors IV, V, VII, X.
* Provided as a lyophilized reagent.
* Used to monitor oral anticoagulant therapy (Warfarin / Coumadin).

PT Reagent Calibration
* Reagents are calibrated against standard PT reagent established by the WHO.
* ISI = International Sensitivity Index.
* ISI is assigned by the manufacturer for each lot of reagent using reference material traceable to WHO.
* The lower the ISI the more sensitive the Reagent
o ISI of 1.8 to 2.4 = Low sensitivity (North American Standard PT)
o ISI of 1.4 to 1.8 = Average sensitivity
o ISI 1.0 to 1.4 = High Sensitivity

PT: INR Values
* INR = International Normalised Ratio.
* MNP = Mean Normal Plasma.
* INR = (PT / MNP)ISI
* An INR of 1.0 means that the patient PT is normal.
* An INR greater then 1.0 means the clotting time is elevated.

INR Calculation
* Example 1
o MNP = 12.0 s
o ISI = 1.25
o Patient Plasma = 20 s
o INR = (20.0 / 12.0)1.25 = 1.9
* Example 2
o MNP = 12.0 s
o ISI = 1.85
o Patient Plasma = 17 s
o INR = (17.0 / 12.0)1.85 = 1.9
* Example 3
o MNP = 12.0 s
o ISI = 1.4
o Patient Plasma = 20 s
o INR = (20.0 / 12.0)1.4 = 2.0
* Example 4
o MNP = 12.0 s
o ISI = 2.0
o Patient Plasma = 20 s
o INR = (20.0 / 12.0)2.0 = 2.8

Expected PT Values
* Mean Normal Plasma = 10 to 14 seconds.
* Mean Normal Plasma value varies with PT sensitivity. A high sensitivity (Low ISI) PT will give a high normal PT value (13 to 15 seconds).
* Oral anticoagulant monitoring = Target INR of 2.0 to 3.0.
* INR of greater than 5 or 5.5 = unacceptable high risk of bleeding.
* %CV between duplicates less than 5%

Performing a PT test
* Pre-warm PT reagent and sample to 37 oC
* Add 100 L sample to cuvette
* Add 200 L of PT reagent to cuvette
* Start timer
* Record time to clot in seconds
* Calculate INR
* see product insert for PT

Activated Partial Thromboplastin Time
* APTT or PTT
* Reagent contains phospholipids and a ‘surface activator’; (Ellagic Acid, Micronized Silica)
* Calcium Chloride reagent added to start the reaction.
* APTT reagent mimics the surface of a platelet.
* Measures activity of clotting factors in the Intrinsic Pathway, factors VIII, IX, XI and XII
* No WHO calibration standard

Uses of APTT
* Sensitive to 30 to 40% deficiencies of all factors except VII and XIII.
* Heparin inhibits the activity of clotting factors in the Intrinsic Pathway.
* A standard curve (APTT time vs Heparin concentration) is prepared using a heparin standard.
* APTT is also sensitive to other non-specific Factor inhibitors such as Lupis Anticoagulant.
* Can be influenced by Vitamin K deficiency and Coumadin therapy.
* Negative APTT result usually rules out Hemophilia.

Expected APTT Values
* Normal Range: 26 to 40 seconds
* Slightly Elevated: 45 to 65 seconds
* Extremely Elevated = > 70 seconds
* %CV less than 7%

Performing an APTT Test
* Pre-warm Calcium Chloride reagent to 37 oC.
* Add 100 microL of sample to cuvette.
* Add 100 microL of APTT to cuvette and incubate for 3 minutes.
* Add 100 microL of Calcium Chloride reagent and start timer.
* Record the time to clot in seconds.
* See APTT product Insert

Heparin Monitoring
* Prepare Heparin Standards
o Prepare stock heparin (10 USP units/mL)
o Prepare working heparin dilutions (0.1 to 0.8 U/mL) by diluting stock in normal plasma
o Run heparin dilutions as samples in APTT assay
* Plot the results as U/mL vs Log Clotting times
* Run patient samples in APTT assay and determine heparin concentration from the plot.

Heparin Calibration Curve
Factor Substitution Tests:
PT and APTT
* Dilute patient sample one to one with adsorbed plasma and serum to determine if normal clotting time is restored.
* Serum: Source of Factors IX, X, XI & XII
* Adsorbed Plasma: Source of Factors VIII, V, XI, & XII

Factor Plots: PT and APTT
* Dilute a normal plasma sample or control 1 to 10 in saline
* Dilute in saline: 100%, 50%, 25%, 12.5%. 6.25%, 3.12%,
* Mix one to one with a factor deficient plasma.
* Measure PT or APTT and plot Log % Factor vs Log clotting time.
* Dilute patient plasma 1 to 10 in saline.
* Mix one to one with a factor deficient plasma.
* All factors will be restored except the deficient factor. If the factor is present in test sample no reduction in clotting will be seen. (Same clotting time as the 100% standard)
* Determine percent factor from standard curve.

Factor Calibration Curve
Plasma Controls
* Used to monitor assay performance (QC)
* Made from pooled normal human plasma with some factors selectively adsorbed.
* Three levels available:
o Level 1 control represents a normal plasma
o Level 2 represents a slightly elevated plasma (INR ~ 1.5)
o Level 3 represents a severely elevated plasma (INR ~ 2.5)
* Each laboratory should establish expected ranges for PT and APTT.

Thrombin Time (TT or TAT)
* Measures common pathway.
* Fibrinogen --> Fibron Clot
* Not sensitive to deficiencies in Intrinsic or Extrinsic pathways.
* Reagent consists of animal thrombin.
* Normal Clotting time is 15 seconds.
* If elevated sample is mixed one to one with normal and re-tested. If normal clotting is not restored then an anti-coagulant is present.
Bleed Time Test
* An incision is made
* Time to stop bleeding is measured
* Normal clotting time is 7.5 minutes

D-Dimer Test
* D-Dimer is a fibrin monomer
* Product of fibrolysis
* Latex agglutination assay is used
* Anti-D-Dimer antibody coated on micro-latex beads
* Cardiac Infarction Marker

Activated Clotting Time (ACT)
* Clotting time of whole blood in the presence of silica based activator.
* Normal clotting times = 90 to 170 sec.
* Used to monitor heparin doses from 1 to 10 U/mL (APTT is sensitive to heparin at 0.2 to 1 U/mL).
* Used with invasive procedures that require on-site adjustment of heparin and protamine dosage. (ex. Cardiopulmonary bypass surgery).
* Not amenable for use with an optical instrument, too cloudy.
* Also called HMT, Heparin Management Test

Fibrin-1 Clot Detection
LIGHT SOURCE
CUVETTE
DETECTOR
Clot Detection
Time in seconds
Optical Density
Change in slope > Threshold = CLOT

Coagulation Testing.ppt

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Immunoassays

Immunoassays
By:Diane C. Jette, Ph.D.
BioMedica Diagnostics Inc.

Test Menu
* Infectious Diseases
* Cardiac Markers
* Cancer Screening
* Fertility / Hormones
* Drugs of Abuse
* Other Tests
o IgE
o Rh Factor
o Occult Blood
o TSH, T3, T4
o Blood Grouping

Test Formats Available
* Latex Agglutination
* DIPSTICK
* Card Format
* Cartridge Format
* ELISA Format with Plate Reader

Structure of IgG
(150,000 Daltons)
Antigen
Binding Site
Fab
Fc

Structure of IgM
(900,000 Daltons)
Binding Sites
Sandwich ELISA Procedure
* Antibody coated on plate.
* Incubate with sample containing antigen.
* Wash away unbound material.
* Incubate with antibody-enzyme conjugate.
* Wash away unbound conjugate.
* Add substrate.
* Enzyme acts on substrate and produces color change.
* Measure amount of color produced.
* Amount of antigen present is proportional to the amount of color produced.

ELISA: Sandwich Format
Sandwich Assay Results
Color Intensity (OD)
Antigen Concentration
Linear Range
ELISA: Inhibition Assay Procedure
* Antigen coated on plate.
* Incubate with sample containing antigen and enzyme-antibody conjugate.
* Antigen in solution binds to enzyme-antibody conjugate preventing binding to antigen on plate.
* Wash away all unbound material.
* Add substrate.
* Enzyme acts on substrate to produce a color change.
* Measure the amount of color.
* The amount of antigen present is inversely proportional to the amount of color produced.
ELISA: Inhibition Format
Inhibition Assay Results
Color Intensity (OD)
Antigen Concentration
Linear Range
Agglutination Assay Procedure
Antibody Detection
* Antigen coated on latex particles.
* Incubate with sample containing antibody.
* Antibody binding to antigen causes cross-linking of latex beads.
* Agglutination is observed.
Antigen Detection
* Antibody coated on latex particles.
* Incubate with sample containing antigen.
* Antigen binding to antibody causes cross-linking of latex beads.
* Agglutination is observed.
Latex Agglutination Assay
Latex Agglutination
Negative Result
Smooth gray appearance
Positive Result
Large aggregates in the center or periphery of the test circle
DIPSTICK Format
Absorbing Pad
Test Area
Maximum Level
Sample Pad
Negative Result
Positive Result
CARD Format
CONTROL
TEST
SAMPLE
Negative Result
CONTROL
TEST
SAMPLE
Positive Result
Cartridge Format
Negative Result
S T C
Positive Result

Immunoassays.ppt

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Urine Analysis

Urine Analysis
By:Diane C. Jette, Ph.D.
BioMedica Diagnostics Inc.


Reagent Test Strips
* Multiple test reagents on a ready to use test strip.
* Test results are read at different times after brief exposure to urine sample.
* The color on strip is compared to the reference color shown on test strip packaging.

Typical Test Strip Test
Glucose
Bilirubin
Ketone
Blood
Protein
Nitrite
Leukocytes
pH
Specific Gravity
Urobilinogen
Sensitivity_
* 4 to 7 mmol/L
* 7 to 14 mol/L
* 0.5 to 1.0 mmol/L (Acetoacetic acid)
* 150 to 620 g/L (Hemoglobin)
* 0.15 to 0.3 g/L (Albumin)
* 13 to 22 mol/L
* 5 to 15 cells/ L
* pH 5.0 to 8.5
* 1.000 to1.030
* 0.2 to 8 mol/L

Glucose
* Small amounts of glucose normally excreted by the kidney.
* Below sensitivity of the test.
* >6 mmol/L clinically significant.

Bilirubin
* Normally no Bilirubin is detected in urine.
* Even trace amounts are clinically significant.
Ketones
* Test detects acetoacetic acid in urine.
* Normal urine negative with this test.
* Detectable levels seen during physiological stress such as fasting, pregnancy, and frequent strenuous exercise.
* Large amounts with ketoacidosis due to starvation and abnormal carbohydrate or lipid metabolism.
Specific Gravity
* Range = 1.000 and 1.030
* Elevated specific gravity seen with elevated protein levels (1 to 7.5 g/L)

Blood
* Test measures hemoglobin and myoglobin.
* Trace amounts may be clinically significant.
* Often found in urine of menstruating females.
* False positives may be seen with urinary tract infections

pH
* Range from pH 5 to 8.5.
* False results may occur if excessive urine remains on the strip.

Protein
* Test sensitive to albumin.
* Negative result does not rule out the presence of hemoglobin or globulins.
* Normally no protein present in urine.
* Greater than 0.3 g/L is clinically significant.

Urobilinogen
* Normal Range in urine = 3 to 17 mol/L
* Greater than 34 mol/L transition from normal to abnormal.
* Total absence of urobilinogen cannot be determined with this test.
Nitrite
* Dependant on the conversion of dietary nitrate to nitrite by Gram Negative Bacteria.
* Positive results may indicate presence of greater than 105 cells per mL.
* Color not proportional to the number of cells.

Leukocytes
* Normally no leukocytes present in urine.
* Positive result is clinically significant.
* Some drugs interfere with the test

Urine Analysis.ppt

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Evaluation of Laboratory Data in Nutrition Assessment

Evaluation of Laboratory Data in Nutrition Assessment
Presentation lecture by:Cinda S. Chima, MS, RD

Laboratory Data and the NCP

* Used in nutrition assessment (a clinical sign supporting nutrition diagnosis)
* Used in Monitoring and Evaluation of the patient response to nutritional intervention

Specimen Types

* Serum: the fluid from blood after blood cells and clot removed
* Plasma: fluid from blood centrifuged with anticoagulants
* Erythrocytes: red blood cells
* Leukocytes: white blood cells
* Other tissues: scrapings and biopsy samples
* Urine: random samples or timed collections
* Feces: random samples or timed collections
* Less common: saliva, nails, hair, sweat

Interpretation of Routine Medical Laboratory Tests

* Clinical Chemistry Panels
o Basic metabolic panel
o Comprehensive metabolic panel
* Complete blood count
* Urinalysis
* Hydration status

Clinical Chemistry Panels: Basic Metabolic Panel (BMP)

o Electrolytes: Na+, K+, Cl-, HCO3 or total CO2
o Glucose
o Creatinine
o BUN

Basic Metabolic Panel Charting Shorthand
Clinical Chemistry Panels: Comprehensive Metabolic Panel Includes
* BMP except CO2
* Albumin
* Serum enzymes (alkaline phosphatase, AST [SGOT], ALT [SGPT]
* Total bilirubin
* Total calcium
Phosphorus, total cholesterol and triglycerides often ordered with the CMP
Complete Blood Count (CBC)
* Red blood cells
* Hemoglobin concentration
* Hematocrit
* Mean cell volume (MCV)
* Mean cell hemoglobin (MCH)
* Mean cell hemoglobin concentration (MCHC)
* White blood cell count (WBC)
* Differential: indicates percentages of different kinds of WBC

Clinical Chemistry Panels: Urinalysis
Types of Assays

* Static assays: measures the actual level of the nutrient in the specimen (serum iron, white blood cell ascorbic acid)
* Functional Assays: measure a biochemical or physiological activity that depends on the nutrient of interest (serum ferritin, TIBC)
o (Functional assays are not always specific to the nutrient)
Assessment of Nutrient Pool
Assessment of Hydration Status

* Dehydration: a state of negative fluid balance caused by decreased intake, increased losses, or fluid shifts
* Overhydration or edema: increase in extracellular fluid volume; fluid shifts from extracellular compartment to interstitial tissues
o Caused by increase in capillary hydrostatic pressure or permeability
o Decrease in colloid osmotic pressure
o Physical inactivity
* Use laboratory and clinical data to evaluate pt
Hypovolemia
Symptoms of Hypovolemia
* Orthostatic Hypotension (caused by change in position)
* Central venous and pulmonary pressures 
* Increased heart rate
* Rapid weight loss
* Decreased urinary output
* Patient cool, clammy
* Decreased cardiac output
* Ask the medical team!!
Treatment of Hypovolemia

* Replace lost fluids with fluids of similar concentration
* Restores blood volume and blood pressure
* Usually isotonic fluid like normal saline or lactated Ringer’s solution given IV
* Excess of isotonic fluid (water and sodium) in the extracellular compartment
* Osmolality is usually not affected since fluid and solutes are gained in equal proportion

Causes of Hypervolemia

* Results from retention or excessive intake of fluid or sodium or shift in fluid from interstitial space into the intravascular space
* Fluid retention: renal failure, CHF, cirrhosis of the liver, corticosteroid therapy, hyperaldosteronism
* Excessive intake: IV replacement tx using normal saline or Lactated Ringer’s, blood or plasma replacement, excessive salt intake
* Fluid shifts into vasculature caused by remobilization of fluids after burn tx, administration of hypertonic fluids, use of colloid oncotic fluids such as albumin

Symptoms of Hypervolemia

* No single diagnostic test, so signs and symptoms are key
* Cardiac output increases
* Pulse rapid and bounding
* BP, CVP, PAP and pulmonary artery wedge pressure rise
* As the heart fails, BP and cardiac output drop
* Distended veins in hands and neck
* Anasarca: severe, generalized edema
* Pitting edema: leaves depression in skin when touched
* Pulmonary edema: crackles on auscultation
* Patient SOB and tachypneic
* Labs: low hematocrit, normal serum sodium, lower K+ and BUN (or if high, may mean renal failure)
* ABG: low O2 level, PaCO2 may be low, causing drop in pH and respiratory alkalosis

Treatment of Hypervolemia

* Restriction of sodium and fluid intake
* Diuretics to promote fluid loss; morphine and nitroglycerine to relieve air hunger and dilate blood vessels; digoxin to strengthen heart
* Hemodialysis or CAVH

Dehydration

* Excessive loss of free water
* Loss of fluids causes an increase in the concentration of solutes in the blood (increased osmolality)
* Water shifts out of the cells into the blood
* Causes: prolonged fever, watery diarrhea, failure to respond to thirst, highly concentrated feedings, including TF

Symptoms of Dehydration

* Thirst
* Fever
* Dry skin and mucus membranes, poor skin turgor, sunken eyeballs
* Decreased urine output
* Increased heart rate with falling blood pressure
* Elevated serum osmolality; elevated serum sodium; high urine specific gravity

Treatment of Dehydration

* Use hypotonic IV solutions such as D5W
* Offer oral fluids
* Rehydrate gradually

Laboratory Values and Hydration: BUN
Laboratory Values and Hydration Status: BUN:Creatinine Ratio
Laboratory Values and Hydration: HCT
Laboratory Values and Hydration: Alb, Na+
Other factors influencing result
Hyper-volemia
Laboratory Values and Hydration Status
Serum albumin
Other factors influencing result
Hypokalemia (K+< 3.5 mEq/L)
Serum Calcium
Hypocalcemia (serum calcium <9.0 mg/dL; ionized Ca+ <4.5 mg/dL)
Serum Phosphorus (normal 3.0-4.5 mg/dL)
Hypophosphatemia (<3.0 mg/dL)
Hyperphosphatemia (>4.5 mg/dL)
Hypomagnesemia <1.3 mEq/L (normal 1.3-2.1 mEq/L)
Hypermagnesemia (>2.1 mEq/L)
Assessment for Protein-Calorie Malnutrition
Hormonal and Cell-Mediated Response to Inflammatory Stress
Nitrogen Balance Studies
Nitrogen Balance Calculations
Nitrogen Balance Challenges
Visceral Proteins: Serum Albumin
Plasma Transferrin
Transthyretin (Prealbumin)
Retinol-Binding Protein
C-Reactive Protein
Inflammation
Urinary Creatinine
Markers of Malabsorption
Lipid Indices of Cardiovascular Risk
Nutrition Diagnoses and Laboratory Indices
Examples of Nutrition Diagnostic Statements Related to Lab Values

Evaluation of Laboratory Data in Nutrition Assessment.ppt

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Basic Clinical Chemistry Lab Testing

Clinical Laboratory Testing – Basic Clinical Chemistry
Presentation lecture by:Cecile Sanders, M.Ed., MT(ASCP),
CLS (NCA)

Purpose of Clinical Chemistry Tests

*Measure levels of substances found normally in human blood that have biological functions. Examples: Glucose, Calcium
*Detect or measure non-functional metabolites or waste products. Examples: Creatinine, Blood Urea Nitrogen (BUN)

Clinical Laboratory Testing - Basic Clinical Chemistry

*Detect or measure substances that indicate cell damage or disease. Examples: Liver enzymes, such as ALT, Cardiac enzymes, such as CK-MB
*Detect or measure drugs or toxic substances. Examples: Dilantin, Drugs of abuse screen
* Types of Specimens for Chemical Analysis
*Whole blood, serum or plasma. The most common specimen is serum, collected in a tube with no anticoagulant so that the blood will clot.
*Urine – often 24 hour collections
*Others – Cerebrospinal Spinal Fluid (CSF) and other fluids

* Collection and Handling of Blood Specimens for Chemical Analysis
*Blood collection tubes for obtaining serum - Serum Separator Tubes (SST) do not have an anticoagulant but do contain a gel substance which will form an interface between the clot and the serum when the blood specimen is centrifuged. These tubes are sometimes referred to as “Tiger Tops”.

*Blood collection tubes for obtaining plasma
*Patient preparation; time of collection; & effects of eating on chemistry analysis

*Some specimens are increased or decreased after eating (ex. Glucose, triglycerides), so it is important to know what the test and collection method call for. Specimens for these tests are usually collected in a fasting state.

*Sometimes serum or plasma appears lipemia (milky) after a patient has eaten a fatty meal. Lipemia affects most chemistry analyses. The blood must be recollected when the patient is fasting.


* Clinical Chemistry Tests
*Normal or Reference Values – range of values for a particular chemistry test from healthy individuals
*Chemistry Panel grouping – some tests are “bundled” according to the system or organ targeted. Examples: thyroid panel, liver panel, cardiac panel, kidney panel, basic metabolic panel, etc.

* Commonly Performed Chemistry Tests or Analytes
*Proteins – essential components of cells and body fluids. Some made by body, others acquired from diet. Provides information about state of hydration, nutrition and liver function, since most serum proteins are made in the liver.

*Electrolytes – sometimes called “lytes”
*Includes sodium (Na), potassium (K), chloride (Cl) and bicarbonate (HCO3-)
*Collectively these have a great effect on hydration, acid-base balance and osmotic pressure as well as pH and heart and muscle contraction
*Levels differ depending on if inside vs. outside cells
*Important in transport of substances into and out of cells

*Minerals
*Calcium
*Used in coagulation and muscle contraction
*99% is in skeleton and is not metabolically active
*Influenced by vitamin D, parathyroid hormone, estrogen and calcitonin
*Hypercalcemia – occurs in parathyroidism, bone malignancies, hormone disorders, excessive vitamin D, and acidosis; may cause kidney stones
*Hypocalcemia – can cause tetany; occurs in hypoparathyroidism, vitamin D deficiency, poor dietary absorption and kidney disease

*Phosphorus
*80% in bone and rest in energy compounds such as ATP
*Influenced by calcium and certain hormones
*Iron
*Essential for hemoglobin
*Deficiency results in anemia; may be caused by lack of iron in diet, poor absorption, poor release of stored iron or loss due to bleeding
*Increased in hemolytic anemia, increased iron intake or blocked synthesis of iron-containing compounds, such as in lead poisoning


*Kidney Function Tests
*Serum Creatinine
*Best test for overall kidney function; not affected by diet or hormone levels
*Waste product of muscle metabolism
*Serum creatinine rises when kidney function is impaired

*BUN (Blood Urea Nitrogen)
*BUN is surplus amino acids that are converted to urea and excreted by kidneys as a waste product
*BUN influenced by diet and hormones, so it is NOT as good an indicator of renal function as serum creatinine levels
*BUN increased in kidney disease, high protein diet, and after administration of steroids
*BUN decreased in starvation, pregnancy and in persons on a low protein diet

*Uric Acid
*Formed from breakdown of nucleic acids and excreted as a waste product by kidneys
*Increased in kidney disease, but most often used to diagnosis gout (pain in joints, mainly big toe, due to precipitated uric acid crystals)
*Also increased in increased cell destruction, such as after massive radiation or chemotherapy

*Liver Function Tests
*Liver functions:
*Synthesizes glycogen from glucose
*Makes plasma proteins (albumin, lipoproteins, coagulation proteins)
*Forms cholesterol and degrades it into bile acids, which emulsifies fats for absorption
*Stores iron, glycogen, vitamins and other substances
*Destroys old blood cells and recycles components of hemoglobin

*Total Bilirubin
*Waste production of hemoglobin breakdown
*Increased in excessive RBC breakdown, such as hemolytic anemia, or impaired liver function or some sort of obstruction, such as a tumor or gall stone

*Liver Enzymes – levels increase following damage to liver tissues
*Alkaline Phosphatase (ALP or AP) - Greatly increased in liver tumors and lesions; moderately increased in diseases such as hepatitis
*Alanine Aminotransferase (ALT; formerly called SGPT) - Increases up to 10x in cirrhosis, infections or tumors and up to 100x in viral or toxic hepatitis


*Asparate Aminotransferase (AST; formerly called SGOT) - Increased in liver disease, but also in heart attacks
*Gamma Glutamyl Transferase (GGT) - Often used to monitor patients recovering from hepatitis and cirrhosis
*Lactate Dehydrogenase (LD) - Increased in liver disease and following heart attacks

*Cardiac Function Tests
*Creatine Kinase (CK) - Widely used to diagnosis and monitor heart attacks
*Troponins
* Only present in heart muscle, making it a more accurate indicator of heart attack than CK
* Cardiac Troponin T (cTnT)
* Cardiac Troponin I (cTnI)
*Lipid Metabolism Tests
*Cholesterol
* Present in all tissues
* Serves as the skeleton for many hormones
* Recommended to be less than 200 mg/dL in adults)
* LDL = “bad” cholesterol; HDL = “good” cholesterol

*Triglycerides
* Main storage form of lipids, comprising 95% of fat tissue
* Hyperlipidemia – having high blood levels of triglycerides – may increase risk of heart attack
*Carbohydrate Metabolism Tests
*Glucose - Largely regulated by insulin

*Thyroid Function Tests

*Thyroid Stimulating Hormone (TSH) - Inverse relationship to thyroid function (the higher the TSH, the lower the thyroid function and vice versa)
*Other less common thyroid tests include T3 and T4
*Hypothyroidism – underactive thyroid gland
*Hyperthyroidism – overactive thyroid gland

Basic Clinical Chemistry.ppt

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