Presentation is loading. Please wait.

Presentation is loading. Please wait.

BLOOD CHEMISTRY AND SEROLOGY

Similar presentations


Presentation on theme: "BLOOD CHEMISTRY AND SEROLOGY"— Presentation transcript:

1 BLOOD CHEMISTRY AND SEROLOGY
CHAPTER 19 BLOOD CHEMISTRY AND SEROLOGY

2 PRETEST True or False Most of the cholesterol found in the blood comes from the intake of dietary cholesterol. The primary use of the cholesterol test is to screen for the presence of coronary heart disease. LDL picks up cholesterol from ingested fats and the liver and carries it to the cells. The function of glucose in the body is to build and repair tissue. Insulin is required for normal utilization of glucose in the body.

3 PRETEST, CONT. True or False
An abnormally low level of glucose in the body is known as hypoglycemia. The hemoglobin A1C test measures the average amount of blood glucose over a 3-month period. An antibody is a substance that is capable of combining with an antigen. Mononucleosis is transmitted through coughing and sneezing. Blood antigens (A, B, Rh) are located on the surface of red blood cells.

4 Content Outline Introduction to Blood Chemistry and Serology
Automated blood analyzers: designed for use in medical office Perform blood chemistry tests in a short period of time Operating manual includes: Operation Test parameters Care and maintenance

5 Blood Chemistry Chemicals are dissolved in liquid part of blood
Quantitative measurement of chemical substances in blood Quantitative test: indicates the exact amount of a substance that is present Most blood chemistry tests require a serum specimen for the analysis.

6 Blood Chemistry, cont. Serum specimen usually required for blood chemistry tests Type of test ordered: depends on clinical diagnosis

7 Automated Blood Chemistry Analyzers
Reflectance photometer: measures light intensity to determine amount of substance present Provides a quantitative measurement of chemical substances or analytes present Examples of blood chemistry analyzers ATAC laboratory system Reflotron Analyzer 7

8 Automated Blood Chemistry Analyzers, cont.
Operating manual explains how to: Collect and handle specimen Perform quality control procedures Test specimen (Personnel available for on-site training) What are quality control procedures? 8

9 Quality Control Quality control: consists of methods and means to ensure that test results are reliable and valid Calibration of the analyzer Running controls Calibration: the use of a standard to check precision of the blood chemistry analyzer If analyzer not properly calibrated: unable to produce accurate results 9

10 Quality Control, cont. Control: consists of a sample with a known value Processed in same way as patient specimen Results should fall within a specified range: Indicated on reference sheet that comes with control When running controls, the MA must document the results. 10

11 Quality Control, cont. Types of controls:
Normal control: results fall within normal range Abnormal control: results fall outside of normal range Low abnormal: below normal range High abnormal: above normal range 11

12 Quality Control, cont. d. If control does not fall within specified range may be caused by: Problems or errors with analyzer Problem with technique used to perform test Problem with chemical reagents Consult operating manual The MA can also get assistance from a technical support person from the manufacturer. 12

13 Quality Control, cont. CLIA requirement: for moderate complexity tests
Calibration: at least every 6 months Two levels of controls: daily Example: Running a normal and high control When problems or errors are identified: Must document action to correct them Medical office running CLIA-waived tests Required to follow manufacturer’s instructions - Include quality control procedures that must be performed What does CLIA stand for? 13

14 Cholesterol White, waxy, fatlike substance (lipid)
Essential for normal functioning of body Important component of cell membranes Used in production of: Hormones Bile 14

15 Cholesterol, cont. Cholesterol in the blood:
Most manufactured by liver Portion comes from individual's diet: dietary cholesterol Found only in animal products (organ meats, egg yolks, dairy products) What patient teaching points would the MA relay to the patient about cholesterol? 15

16 Cholesterol, cont. Cholesterol level determined by: Genetic makeup
Amount of dietary cholesterol and saturated fat consumed What do we mean by “genetic makeup”? 16

17 Cholesterol, cont. High cholesterol: excessive amount of cholesterol in blood May cause atherosclerosis Atherosclerosis: buildup of fatty deposits (plaque) on the walls of the arteries As progresses: arteries become more occluded Can lead to heart attack or stroke Are there medications for high cholesterol? 17

18 Cholesterol, cont. High blood cholesterol: risk factor for coronary heart disease (CHD) Efforts should be made to lower cholesterol level 18

19 HDL and LDL Cholesterol
Cholesterol transported in blood as a complex molecule known as a lipoprotein Lipoprotein: A complex molecule consisting of protein and a lipid fraction such as cholesterol Lipoproteins function in transporting lipids in the blood 19

20 HDL and LDL Cholesterol, cont.
Two types of lipoproteins: LDL: low-density lipoprotein HDL: high-density lipoprotein Which type of lipoproteins do we want to lower? 20

21 HDL and LDL Cholesterol, cont.
Picks up cholesterol from ingested fats and the liver Delivers it to blood vessels and muscles where it is deposited in cells 21

22 HDL and LDL Cholesterol, cont.
Often referred to as "bad cholesterol" Excess causes plaque to build up on the arterial walls (atherosclerosis) Risk factor for CHD Even though LDL is considered “bad cholesterol,” does a person still need it? 22

23 HDL and LDL Cholesterol, cont.
Removes excess cholesterol from cells Carries it to liver to be excreted Protective and beneficial to the body 23

24 HDL and LDL Cholesterol, cont.
Often called "good cholesterol" High HDL cholesterol level: reduces risk of CHD Below 40 mg/dL: risk factor for CHD Can a person have too much HDL? 24

25 Cholesterol Testing Adults over age 20: Initial testing includes:
Should have a cholesterol test every 5 years Initial testing includes: Total cholesterol determination Combined measurement of LDL and HDL cholesterol What specimen would the MA collect for cholesterol testing? 25

26 Cholesterol Testing, cont.
Most physicians also order HDL determination Measures only HDL cholesterol in the blood Elevated results: usually require confirmation through further testing Before diagnosis of high blood cholesterol can be made What is the medical term for high cholesterol? 26

27 Interpretation of Results
Total cholesterol Desirable: Below 200 mg/dL Borderline high: 200 to 239 mg/dL High: 240 mg/dL or higher 27

28 Interpretation of Results, cont.
High category: increased risk for CHD Borderline high category: at increased risk if other risk factors present Example: overweight, smoker What instructions might you give a patient who is overweight and has high cholesterol? 28

29 Interpretation of Results, cont.
HDL Cholesterol Optimal: 60 mg/dL or above Desirable: 45 to 59 mg/dL Borderline low: 40 to 45 mg/dL Increased risk for CHD: Below 40 mg/dL 29

30 Patient Preparation Total cholesterol and HDL cholesterol:
Fasting not usually required What does it mean when we ask a patient to fast for a test? 30

31 Patient Preparation, cont
If total cholesterol level is 200 mg/dL or higher: lipid profile usually ordered Lipid profile includes: Total cholesterol HDL cholesterol LDL cholesterol Triglycerides Some physicians prefer the patient to be in a fasting state for cholesterol determinations. This test may also be used as a secondary aid in the study of thyroid and liver function. 31

32 Patient Preparation, cont.
Triglycerides affected by food consumption Patient must fast For at least 12 hours before test Fasting: Abstaining from food or fluids (except water) for a specified amount of time before the collection of a specimen What are triglycerides? 32

33 Patient Preparation, cont.
Interpretation of Test Results Triglycerides Normal: Below 150 mg/dL Borderline high: 150 to 199 mg/dL High: 200 to 499 mg/dL Very high: 500 mg/dL or higher Increased risk for CHD: Over 150 mg/dL 33

34 Patient Preparation, cont.
LDL Cholesterol Optimal: Below 100 mg/dL Near optimal: 100 to 129 mg/dL Borderline high: 130 to 159 mg/dL High: 160 to 189 mg/dL Very high: 190 mg/dL or higher 34

35 What Would You Do? What Would You Not Do?

36 What Would You Do? What Would You Not Do?

37 Blood Urea Nitrogen Blood urea nitrogen (BUN): kidney function test
Urea: end product of protein metabolism Normally present in blood Kidney disease: may cause abnormal increase in BUN What are some symptoms of kidney disease? 37

38 Blood Glucose Glucose: end product of carbohydrate metabolism
Function of glucose: chief source of energy for body Energy needed to: Carry out normal body functioning Maintain body temperature The body maintains a constant glucose level to ensure a continuous source of energy. Why does the body need an energy source? 38

39 Blood Glucose, cont. Glucose can be stored as glycogen for later use in: Muscle tissue Liver tissue glycogen in muscle and liver tissue for later use When no more tissue space available to store glycogen: Glucose is converted to fat and stored as adipose tissue 39

40 Blood Glucose, cont. Insulin
Hormone secreted by beta cells of pancreas Required for normal utilization of glucose Enables glucose to enter cells and be converted to energy Also needed for proper storage of glycogen in liver and muscle cells What disease requires insulin injections for the patients who have it? 40

41 Blood Glucose, cont. Blood Glucose Testing
Glucose measurement used to detect: Diabetes mellitus Hypoglycemia Liver and adrenocortical dysfunction 41

42 Blood Glucose, cont. Testing methods Fasting blood sugar (FBS)
2-hour postprandial glucose test (PPBS) Glucose tolerance test (GTT) What does “postprandial” mean? 42

43 Fasting Blood Sugar FBS: patient must be fasting
No food or fluid (except water) for 12 hours before test If a patient needs to be fasting, for when should the MA schedule the test procedure? 43

44 Fasting Blood Sugar, cont.
Medications that may affect test: Oral contraceptives Salicylates Diuretics Steroids What is a salicylate? 44

45 Fasting Blood Sugar, cont.
Physician may restrict medications before testing Test should be scheduled in the morning Minimizes patient inconvenience due to fasting FBS normal range: 70 to 110 mg/dL 45

46 Fasting Blood Sugar, cont.
Purpose of FBS Evaluate progress of diabetic patients Regulate treatment of diabetic patients Routine screening procedure to detect diabetes If a patient taking insulin has a high reading, what might the physician do to the treatment regimen? 46

47 Fasting Blood Sugar, cont.
FBS above 120 mg/dL: dividing point between normal and hyperglycemic values Indicative of diabetes mellitus Elevated FBS: further testing required (e.g., GTT) 47

48 Two-Hour Postprandial Blood Sugar
Purpose Screen for presence of diabetes Monitor effects of insulin dosage in diagnosed diabetes 48

49 Two-Hour Postprandial Blood Sugar, cont.
Fasting required: beginning at midnight until breakfast Breakfast: Patient consumes a prescribed meal containing 100 grams of carbohydrates Alternative: drink 100 grams of glucose solution Blood specimen collected 2 hours after consumption Nondiabetic patient: glucose returns to normal within 1½ to 2 hours The MA should give the patient written instructions about the test. Why is this important? 49

50 Two-Hour Postprandial Blood Sugar, cont.
Diabetic patient: does not return to fasting level 140 g/dL or higher: suggestive of diabetes Warrants further testing 50

51 Glucose Tolerance Test (GTT)
Provides more detailed information on glucose utilization Assesses insulin response to glucose load Used to diagnose: Diabetes mellitus Hypoglycemia Liver and adrenocortical dysfunction What is hypoglycemia? 51

52 Glucose Tolerance Test (GTT), cont.
Testing Requirements High carbohydrate diet for 3 days before test (150 grams) Fasting What can the MA do to make it easy for the patient to know which foods to consume? (diet sheet) 52

53 Glucose Tolerance Test (GTT), cont.
Testing procedure FBS performed and urine is tested for glucose If FBS indicates hyperglycemia: notify physician Hyperglycemia contraindicates administering the glucose solution After FBS: patient drinks measured amount of glucose (100 grams) Why would you not want to give a patient the glucose solution if the FBS is high? 53

54 Glucose Tolerance Test (GTT), cont.
Blood and urine specimens collected at intervals: 30, 60, 120, and 180 minutes Label blood and urine specimens with exact time of collection 54

55 Glucose Tolerance Test (GTT), cont.
Restrictions during test No eating or drinking except water: affects glucose level Encourage water: easier to produce urine specimen No smoking: stimulant that increases blood glucose level Remain at test site: so patient is present for specimen collection Minimize activity: activity uses glucose Affects test results It is important to let the patient know how long the procedure will take. Why should the MA let the patient know this? 55

56 Glucose Tolerance Test (GTT), cont.
Side Effects Patient may exhibit normal side effects during the test Weakness Feeling of faintness Perspiration Reassure patient that it is only temporary Explain why these symptoms may occur. 56

57 Glucose Tolerance Test (GTT), cont.
Serious symptoms: immediately report to physician Indicate severe hypoglycemia Headache Pale Cold and clammy skin Irrational speech or behavior Profuse perspiration Fainting Why would a patient exhibit symptoms of hypoglycemia? 57

58 Glucose Tolerance Test (GTT), cont.
Interpretation of Results Nondiabetic patient after ingestion of glucose solution Glucose absorbed into bloodstream Rises to a peak level: between 160 and 180 mg/dL Approximately 30 to 60 minutes after consumption of glucose solution 58

59 Glucose Tolerance Test (GTT), cont.
Pancreas secretes insulin to compensate for rise Blood glucose returns to fasting level within 2 to 3 hours Urine is negative for glucose 59

60 Glucose Tolerance Test (GTT), cont.
Diabetic patient after ingestion of glucose solution Blood glucose level peaks at a much higher level Glucose present in urine Blood glucose levels above normal throughout test Due to lack of insulin 60

61 Glucose Tolerance Test (GTT), cont.
Hypoglycemia Blood glucose is abnormally low During GTT patients exhibits low level Beginning at 2-hour interval Continues up to 4 to 5 hours 61

62 Glucose Tolerance Test (GTT), cont.
Hypoglycemia results from: Glucose removed from blood at an excessive rate Decreased secretion of glucose into blood 62

63 Glucose Tolerance Test (GTT), cont.
Hypogylcemia can be caused by: Overdose of insulin Addison's disease Bacterial sepsis Pancreatic cancer Hepatic necrosis Hypothyroidism What is Addison’s disease? 63

64 Glucose Tolerance Test (GTT), cont.
GTT not required if: FBS is above 140 mg/dL 2-hour PPBS is above 180 mg/dL Results greater than these amounts: qualify for diabetes diagnosis 64

65 What Would You Do? What Would You Not Do?

66 What Would You Do? What Would You Not Do?

67 Tests for Management of Diabetes
Important for diabetic patients to manage their condition Best accomplished: keeping blood glucose levels close to normal Patient experiences fewer symptoms Delays or prevents long-term complications Leads to a longer life How do diabetic patients monitor their glucose levels at home? 67

68 Tests for Management of Diabetes, cont.
Types of tests Self-monitoring of blood glucose Performed by patient at home Measures day-day fluctuations in blood glucose level 68

69 Tests for Management of Diabetes, cont.
Hemoglobin A1C test Ordered by physician Provides overall picture of blood glucose level over a period of time 69

70 Self-Monitoring of Blood Glucose (SMBG)
Diabetic patients: usually cannot tell by the way they feel Whether blood glucose is within normal range Only way to know for sure: SMBG Provides patient with feedback for maintaining normal blood glucose level Assists in anticipating and treating fluctuations in blood glucose caused by: What are some possible long-term complications of diabetes that monitoring of blood glucose levels may help avoid? (retinopathy, peripheral vascular disease) 70

71 Self-Monitoring of Blood Glucose (SMBG), cont.
Assists in anticipating and treating fluctuations in blood glucose caused by: Food Exercise Stress Infection 71

72 Self-Monitoring of Blood Glucose (SMBG), cont.
Insulin-dependent diabetic patients: Must monitor glucose at home for effective management Based on results: decisions can be made regarding insulin and dietary adjustments To maintain normal blood glucose levels Avoids extremes of hypoglycemia and hyperglycemia What foods should a diabetic patient avoid? 72

73 Self-Monitoring of Blood Glucose (SMBG), cont.
Reduces symptoms of the disease Helps delay or prevent long-term complications Examples: Retinopathy, peripheral vascular disease Describe retinopathy. 73

74 Self-Monitoring of Blood Glucose (SMBG), cont.
Frequency of Testing Depends on: Severity of the diabetes Diet Presence of special conditions (e.g., pregnancy) Activity level The FBS test result (obtained in the morning) is the best overall indicator of control. 74

75 Self-Monitoring of Blood Glucose (SMBG), cont.
Insulin-dependent diabetic patient: Ideally should monitor four times a day In the morning: after an 8-hour fast (best overall indicator of control) Before lunch Before dinner Bedtime Before lunch, dinner, and at bedtime: provide guidance for adjusting insulin dosage, diet, and exercise The MA should instruct the patient to keep a diary of glucose levels. 75

76 Self-Monitoring of Blood Glucose (SMBG), cont.
Test Results Blood glucose levels Measured using a glucose meter Results displayed in mg/dL (milligrams per deciliter) The MA may need to teach the patient how to use the monitor. 76

77 Self-Monitoring of Blood Glucose (SMBG), cont.
Diabetic patients: should keep a record of daily glucose test results For periodic review by the physician Assists physician in making decisions regarding diabetic management plan 77

78 Self-Monitoring of Blood Glucose (SMBG), cont.
Advantages of SMBG: Most effective way to maintain normal blood glucose level High blood glucose for a long period of time (above 180 mg/dL) Causes progressive damage to body organs leading to: Blindness Kidney disease Nerve damage Circulation problems What are some problems diabetic patients have due to circulation problems? 78

79 Self-Monitoring of Blood Glucose (SMBG), cont.
Convenience of testing No physician order required Can test any time of day Can test when side effect occurs (e.g., hypoglycemia) Treatment can be instituted immediately The patient should carry the monitor and his or her medications with him or her at all times. Why is this important? 79

80 Self-Monitoring of Blood Glucose (SMBG), cont.
More involvement in self-management decisions Insulin dosage, meal planning, physical activity 80

81 Self-Monitoring of Blood Glucose (SMBG), cont.
Reliable decisions can be made regarding insulin dosage During situations that affect blood glucose level: Illness Emotional stress Increased physical activity Suspected hypoglycemia 81

82 Self-Monitoring of Blood Glucose (SMBG), cont.
Prevent or delay in long-term complications Increases chance of staying healthy 82

83 What Would You Do? What Would You Not Do?

84 What Would You Do? What Would You Not Do?

85 Hemoglobin A1C Test (Hb A1C)
Assessment of average amount of glucose in the blood: over a 3-month period Food consumed containing glucose Glucose absorbed into circulation 85

86 Hemoglobin A1C Test (Hb A1C), cont.
Glucose has sticky quality Sticks to protein making up hemoglobin (glycosylation) Hemoglobin: found in red blood cells (RBCs) Function: transports oxygen to tissues of body 86

87 Hemoglobin A1C Test (Hb A1C), cont.
Glycosylation: the process of glucose attaching to hgb Occurs in all individuals Both diabetic and normal Forms a compound: hemoglobin A1C 87

88 Hemoglobin A1C Test (Hb A1C), cont.
Amount of glucose that attaches to hgb: Proportional to amount of glucose in an individual's blood Undiagnosed or poorly controlled diabetic patients Have a higher than normal blood glucose level More Hb A1C forms in these patients What are some things diabetic patients do that lead to poorly controlled diabetes? 88

89 Hemoglobin A1C Test (Hb A1C), cont.
Hb A1C test: measures the percentage of Hb A1C Attachment of glucose to hemoglobin: permanent for life of RBC (90 to 120 days) Provides overall picture of blood glucose for the past 3 months 89

90 Hemoglobin A1C Test (Hb A1C), cont.
Interpretation of Results Normal individuals: 4% to 6% Diabetic individuals: Recommendation: Less than 7% Better chance of delaying or preventing diabetic complications If higher than 8%: change in diabetic management plan required What do IDDM and NIDDM mean? 90

91 Hemoglobin A1C Test (Hb A1C), cont.
Testing recommendations When patient is first diagnosed with diabetes Several times after management plan has been prescribed for a newly diagnosed patient To verify blood glucose control is being achieved HbA1c is run using what specimen? 91

92 Hemoglobin A1C Test (Hb A1C), cont.
c. For diagnosed diabetic patients: to evaluate effectiveness of mgt plan Stable diabetic patients under good control: At least 2 times a year (every 6 months) Patients who have difficulty maintaining control: Test ordered more frequently d. After physician makes an adjustment to diabetic management plan To assess effectiveness of change in treatment 92

93 Glucose Meters Quantitatively measures blood glucose

94 Glucose Meters, cont. On-site testing Provides immediate results
Physician can make decisions regarding: Diagnosis Treatment Follow-up care The MA will perform the test using the glucose meter. 94

95 Glucose Meters, cont. Reagent Test Strips
Plastic strip with a reaction pad Pad contains chemicals: react with glucose in blood Why is it important not to touch the pad on the chemical strip?

96 Glucose Meters, cont. Results displayed as a digital readout in mg/dL

97 Glucose Meters, cont. Storage: cool, dry area at room temperature with cap tightly closed: Chemicals on strip: sensitive to heat, light, and moisture Causes deterioration of chemicals Leads to inaccurate test results Where would be a proper place to store the equipment in the medical office? 97

98 Glucose Meters, cont. Strips that are discolored or have darkened: discard To prevent inaccurate test results Container includes desiccant Absorbs moisture to promote dryness Strips have an expiration date. Why is it important not to use if expiration date has passed? 98

99 Glucose Meters, cont. Care and Maintenance of Glucose Meter
Handle carefully Physical jar could result in malfunction Do not place in high humidity area (e.g., bathroom) 99

100 Glucose Meters, cont. Do not expose to severe variations in environmental temperature Example: Leaving in a vehicle on a hot/cold day 100

101 Glucose Meters, cont. Clean meter properly Exterior of meter:
Use a soft, clean cloth dampened with mild cleaning agent Dry thoroughly Do not let water run into glucose meter Could damage internal components Why is it important to clean the monitor? 101

102 Glucose Meters, cont. Replace battery
Screen displays alert of low battery Directions for installation: specified in operator's manual 102

103 Glucose Meters, cont. Calibration Procedures Purpose of calibration:
Ensures the glucose meter is functioning properly Ensures accurate and reliable test results Programs the electronics of the glucose meter to match reactivity of strips in current use (compensates for variables in the manufacturing process of the reagent strip) Where would you find the calibration device that matches the strips? 103

104 Calibrating the Meter The code should match the numbers on the strips.

105 Glucose Meters, cont. Control Procedure Ensures:
Test results are reliable and valid Errors are eliminated Commercially available glucose control solutions Use two of the following levels of controls High Low What would you do if control levels were out of range? (See slide 107.) 105

106 Glucose Meters, cont. -Solution is sensitive to heat, light, moisture
c. Control solution Effective for 3 months from date opened After opening: write date on label Can be used for (whichever comes first): 3 months from date opened Expiration date stamped on label Store control in cool, dry area at room temperature -Solution is sensitive to heat, light, moisture Why is it important to write the date on the label once opened? 106

107 Glucose Meters, cont. d. If control results not within acceptable range: Check expiration date of test strips and control solution Make sure test strips were stored at room temperature Make sure code on meter matches code on test strips Review technique used to run control procedure Correct any errors and run control again If still not in acceptable range: contact manufacturer

108 Glucose Meters, cont. e. Should be performed
Daily, before using meter for first time When new container of reagent strips is opened If cap left off vial of strips for a length of time If meter is dropped If test has been repeated and result is lower or higher than expected 108

109 Serology Study of the serum of the blood
Specifically deals with the study of antigen and antibody reactions Antigen: a substance capable of stimulating the formation of antibodies Examples: Bacteria, viruses, bacterial toxins, allergens, blood antigens Antibody: a substance capable of combining with an antigen Results in an antigen-antibody reaction 109

110 Serology, cont. Use of serology tests
Assess the presence of a substance Example: ABO blood typing Diagnosis of disease Example: Mononucleosis testing Follow the course of a disease Why would we perform the test for ABO blood typing? 110

111 Serologic Tests Hepatitis Test: detection of viral hepatitis
Five types of viral hepatitis: A, B, C, D, E Determines specific type of hepatitis For what type of hepatitis can we be immunized? 111

112 Serologic Tests, cont. Syphilis Test
Sexually transmitted disease caused by Treponema pallidum Screening tests most commonly used VDRL (Venereal Disease Research Laboratory) RPR (Rapid Plasma Reagin) Is there a cure for syphilis? 112

113 Serologic Tests, cont. Syphilis results reported as:
Nonreactive: negative Weakly reactive: positive Reactive: positive Positive result warrants more specific testing Is syphilis contagious? 113

114 Serologic Tests, cont. Mononucleosis (mono) Test
Detects presence of infectious mononucleosis Rheumatoid Factor (RF) Rheumatoid arthritis (RA): chronic inflammatory disease that affects joints Blood of individual with RA: contains rheumatoid factor (RF) Test detects presence of RF antibodies Assists in diagnosis of rheumatoid arthritis What is mononucleosis? What are symptoms of RA? 114

115 Serologic Tests, cont. Antistreptolysin O test Detects ASO antibodies
Used to detect conditions resulting from strep infections and secondary strep infections: Rheumatic fever Glomerulonephritis Bacterial endocarditis Scarlet fever What does it mean when we have a “secondary” strep infection? 115

116 Serologic Tests, cont. C-Reactive Protein (CRP)
CRP appears in blood: during inflammation and tissue destruction Used to diagnose and determine progress of: Rheumatoid arthritis Acute rheumatic fever Widespread malignancy Bacterial infections A rheumatoid factor and CRP may be run together. 116

117 Serologic Tests, cont. Cold Agglutinins
Detect presence of cold agglutinin antibodies Cold agglutinins found in patients with: Infectious mononucleosis Mycoplasmal pneumonia Chronic parasitic infections Lymphoma Name a chronic parasitic infection. 117

118 Serologic Tests, cont. ABO and Rh Blood Typing
Determines ABO and Rh blood type Purpose Prevent blood transfusion or transplant reactions Identify problems (e.g., hemolytic disease of newborn) 118

119 Serologic Tests, cont. Rh Antibody Titer
Determines amount of Rh antibodies in the blood Can occur in a pregnant woman Rh-negative woman carrying Rh-positive fetus Most frequent use of test: Detect Rh incompatibility problem with a mother and an unborn child The father may also need to be tested for the Rh antibody. 119

120 Rapid Mononucleosis Testing
Infectious mononucleosis: acute infectious disease caused by Epstein-Barr virus (EBV) Most frequently affects children and young adults Transmitted: saliva by direct oral contact Often called "kissing disease" Describe Epstein-Barr virus to the students. 120

121 Rapid Mononucleosis Testing, cont.
Symptoms Mental and physical fatigue Fever Sore throat Severe weakness Headache Swollen lymph nodes What are some medications that may help alleviate the symptoms of mono (mononucleosis)? 121

122 Rapid Mononucleosis Testing, cont.
Rapid mononucleosis test: often performed in medical office Assists in diagnose of infectious mononucleosis Individuals with mononucleosis: produce heterophile antibody Usually by sixth to tenth day of the illness Test detects this antibody How would you describe to the patient how you are going to obtain the specimen? 122

123 Rapid Mononucleosis Testing, cont.
A positive mononucleosis test and patient symptoms Basis for diagnosis of infectious mononucleosis What might be some patient teaching points for avoiding the spread of mono (mononucleosis)? 123

124 Blood Typing Blood Antigens Each individual has a blood type
Depends on antigens on the surface of RBCs Blood antigen: A protein present on the surface of RBCs that determines a person's blood type Inherited through genes Programs the body to produce a particular antigen 124

125 Blood Antigens, cont. Blood antigens: Grouped into categories known as blood group systems ABO and Rh blood group systems: Most likely to cause problems in: Blood transfusions Rh disease of newborn Most commonly tested for in medical laboratory 125

126 Blood Antigens, cont. ABO blood group system:
Type A blood: A antigen present Type B blood: B antigen present Type AB blood: A and B antigens present Type O blood: Neither A or B antigen is present 126

127 ABO Blood Antigens

128 Blood Antibodies Blood antibody: A protein present in the plasma that is capable of combining with its corresponding blood antigen To produce an antigen-antibody reaction 128

129 Blood Antibodies, cont. Body never produces an antibody to combine with its own blood antigen Example: If blood type is A: Plasma does not contain the A antibody B antibody naturally occurs in this patient's plasma B antibody cannot combine with A antigen 129

130 Blood Antibodies, cont. If a blood antigen and its corresponding antigen combine: A serious antigen-antibody reaction takes place 130

131 Blood Antibodies, cont. Antibodies present Type A blood: B antibody
Type B blood: A antibody Type AB blood: Neither A or B antibody Type O blood: Both A and B antibodies 131

132 The Rh Blood Group System
Discovered by Landsteiner and Weiner While working with rhesus monkeys (1940) Rh-positive: Have Rh antigen present on the surface of RBCs Most of population is Rh-positive Unlike the A and B antibodies, the Rh antibodies do not normally occur in the plasma. 132

133 The Rh Blood Group System, cont.
Rh-negative 15% of white population do not have Rh antigen 7% of black population do not have Rh antigen 133

134 Blood Antigen and Antibody Reactions
When blood antigen and its corresponding antibody unite Results in clumping of RBCs: known as agglutination Can be serious or fatal if occurs in the living body (in vivo) Clumped RBCs cannot pass through small tubules of kidneys Results in kidney failure Eventually leads to hemolysis Can occur if wrong blood type administered during transfusion When would a patient receive a blood transfusion? A person can bank his or her own blood for transfusion. 134

135 Agglutination and Blood Typing
Agglutination of RBCs: basis for ABO and Rh blood typing Antigen-antibody reaction occurs in vitro What does “in vitro” mean? 135

136 Agglutination and Blood Typing, cont.
To perform blood typing: Commercially prepared antiserum used Antiserum: a serum containing antibodies Added to an unknown blood specimen Example: Antiserum with A antibody added to unknown blood specimen If A antigen present: combines with A antibody Results in agglutination: indicates type A blood What does agglutination look like? 136

137 Antigen Antibody Reaction

138 POSTTEST True or False Serum is required for most blood chemistry tests. The buildup of plaque (due to high cholesterol) on the walls of arteries is known as thrombophlebitis. An HDL cholesterol level greater than 50 mg/dL is a risk factor for coronary heart disease. The triglyceride test requires that the patient not eat or drink for 12 hours before the test. The normal range for a fasting blood sugar is 120 to 160 mg/dL.

139 POSTTEST, CONT. True or False
The glucose tolerance test is used to assist in the diagnosis of diabetes mellitus. Before meals, it is recommended that the blood glucose level for a diabetic patient fall between 60 to 80 mg/dL. The recommended A1C level for an individual with diabetes is 4 % to 6%. The RPR test is a screening test for syphilis. The varicella virus causes infectious mononucleosis


Download ppt "BLOOD CHEMISTRY AND SEROLOGY"

Similar presentations


Ads by Google