Laboratory Investigations PDF

Laboratory Investigations Asooc. Prof. Dr. Maha Abdelkawy Fahmy Oral Medicine and Periodontology Department Faculty of dentistry ,Beni-suef university  Laboratory Investigations 1-Haemogram (CBC) I Red blood cell count (RBC/mm3)...

Laboratory Investigations Asooc. Prof. Dr. Maha Abdelkawy Fahmy Oral Medicine and Periodontology Department Faculty of dentistry ,Beni-suef university  Laboratory Investigations 1-Haemogram (CBC) I Red blood cell count (RBC/mm3) 2- Tests for Haemostasis II Hemoglobin concentration (Hb %) III Total white blood cell count 3- Tests for Diabetes Mellitus (WBC/mm3) IV Differential white blood cell count 4- Blood Chemistry V Platelet count VI Erythrocyte Sedimentation Rate (ESR) 5-Biopsy  Laboratory Investigations 1-Haemogram (CBC) I Red blood cell count (RBC/mm3) 2- Tests for Haemostasis II Hemoglobin concentration (Hb %) I. Testing Capillary Function III Total white blood cell count 3- Tests for Diabetes Mellitus II - Testing Platelet Function (WBC/mm3) IV III. Differential white blood Testing the Clotting cell count Factors 4- Blood Chemistry V Platelet count VI Erythrocyte Sedimentation Rate (ESR) 5-Biopsy  Laboratory Investigations 1-Haemogram (CBC) 1) Test Paper Strips: 2) Blood Glucose Level: 2- Tests for Haemostasis 3) Glucose Tolerance test: 4) Urinary Glucose: 3- Tests for Diabetes Mellitus 5) Glycosylated Haemoglobin 4- Blood Chemistry (HbA1C) 6) Ketoacidosis 5-Biopsy 7) Self assessment tests  Laboratory Investigations 1-Haemogram (CBC) I1) RedTest Paper blood cell Strips: count (RBC/mm3) 2- Tests for Haemostasis II2)Hemoglobin Blood Glucose Level: (Hb %) concentration I. Testing Capillary Function A. Tests to check 3)Total Glucose Liver function III whiteTolerance test: blood cell count 3- Tests for Diabetes Mellitus II 4)- Testing (WBC/mm3) B. Urinary Platelet Function Glucose: Tests to check Kidney function IV III. 5) Differential Testing white the Clotting Glycosylated blood cell count Factors Haemoglobin 4- Blood Chemistry C. Tests for patients with multiple jaw V(HbA1C) Platelet count bone lesions VI Erythrocyte Sedimentation Rate (ESR) 5-Biopsy 6) Ketoacidosis 7) Self assessment tests  Laboratory Investigations 1-Haemogram (CBC) I1) RedTest Paper blood cell Strips: count (RBC/mm3) 2- Tests for Haemostasis II2)Hemoglobin Blood Glucose Level: (Hb %) concentration I. Testing Capillary Function A. Tests to check 3)Total Glucose Liver function III whiteTolerance test: blood cell count 3- Tests for Diabetes Mellitus II 4)- Testing (WBC/mm3) B. Urinary Platelet Function Glucose: Tests to check Kidney function IV III. 5) Differential Testing white the Clotting Glycosylated blood cell count Factors Haemoglobin 4- Blood Chemistry C. Tests for patients with multiple jaw V(HbA1C) Platelet count bone lesions VI Erythrocyte Sedimentation Rate (ESR) 5-Biopsy 6) Ketoacidosis 7) Self assessment tests  · Red blood cell count (RBC/mm3) It 1-Haemogram includes: · Hemoglobin concentration (Hb %) · Total white blood cell count (WBC/mm3) (Complete Blood Count) · Differential white blood cell count · Platelet count · Erythrocyte Sedimentation Rate (ESR) Why needed by dentist? 1. Some blood diseases show oral manifestations (anemia, leukemia) 2. Some blood diseases require certain precautions and management during dental procedures for the patient’s safety (bleeding disorders...). 3. It shows the systemic response of the patient to oral infection. 4. It shows specific changes that may denote bacterial, viral and parasitic infections as well as immunologic and malignant diseases.  I. Red Blood Corpuscles (Erythrocytes) 1 - The main function of RBCs  I. Red Blood Corpuscles (Erythrocytes) under control of pituitary Erythropoietin produced production of RBCs from gland. by the kidney bone marrow Any decrease in O2 tension in will lead to increased tissues Thus decreasing increased level of production of the O2 carrying or erythropoietin RBCs, by the bone capacity decrease in Hb % in leading to marrow. RBCs  I. Red Blood Corpuscles (Erythrocytes) Maturation of R.B.Cs: New born RBCs, are known as reticulocytes (1-2 % of RBCs count in peripheral blood) which are still carrying remnants of RNA and ribosomes, mature RBCs, are unnucleated and contain no RNA. Its life span is 120 days then become destroyed in liver and spleen. Normal mature RBCs, are biconcave discs, 2 microns in thickness. I. Red Blood Corpuscles (Erythrocytes) (A) Count (B) (C) Indices Morphology I. Red Blood Corpuscles (Erythrocytes) (A) RBCs count: Males 5.5 ±1 Females 4.8 ± 1 millions/mm3 millions/mm3 I. Red Blood Corpuscles (Erythrocytes) (A) RBCs count: Polycythemia more than 6.5 millions /mm3) Erythrocytopenia or Anemia (less than 4 millions/mm3  I. Red Blood Corpuscles (Erythrocytes) (A) RBCs count: Erythrocytopenia or Anemia (less than 4 millions/mm3 Decreased production Decreased maturation Increased destruction /loss Aplastic pernicious Hemolytic anemia, anemia, anemias, bone marrow folic acid deficiency hemorrhage disease anemia, Renal iron deficiency disease anemia I. Red Blood Corpuscles (Erythrocytes) (A) RBCs count: Anemia 1- Decreased production (aplastic anemia, bone marrow disease, renal disease) (1) Decreased RBC count (2) Decreased reticulocyte count (normally: 1-2% of RBCs count). (3) No or little change in RBCs morphology (normocytic, normochromic anemia). I. Red Blood Corpuscles (Erythrocytes) (A) RBCs count: Anemia 2- Decreased maturation (pernicious anemia, folic acid deficiency anemia, iron deficiency anemia) (1) Decreased RBC count (2) Increased reticulocyte count (3) Change in RBC morphology: - Macrocytic anemia in pernicious and folic acid deficiency anemias Microcytic anemia in iron deficiency anemia. I. Red Blood Corpuscles (Erythrocytes) (A) RBCs count: Anemia 3- Increased destruction /loss (hemolytic anemias, hemorrhage) (1) Decreased RBC count (2) Increased reticulocyte count (bone marrow is actively producing immature forms to compensate the loss of RBCs). (3) RBC morphology: - No changes in cases of anemia due to increase blood loss. - Certain morphologic changes are observed in hemolytic anemias as Sickle shaped RBCs in Sickle cell anemia and Fragments of RBCs (Schistocytes).  I. Red Blood Corpuscles (Erythrocytes) (A) RBCs count: Erythrocytopenia or Anemia (less than 4 millions/mm3) Decreased production Decreased maturation Increased destruction /loss Increas Increas Decreas ed Decreas ed Decreased No or Change in RBC ed RBC reticulo RBC morphology: reticulocy ed RBC reticulo little morphology: count cyte te count count cyte Decreas change count (normally: count ed RBC in RBCs count 1-2% of morpho RBCs logy count). Certain Macrocytic Microcytic No morpho anemia anemia change logic s change I. Red Blood Corpuscles (Erythrocytes) morphologic features of RBCs: Anisocytosis: variation in RBCs size Normocytic: normal RBCs size. Microcytic: abnormally small RBCs Macrocytic: abnormally large RBCs. Megalocytes: extremely large RBCs. Poikilocytosis: variation in RBCs shape Sickle-shaped RBCs in sickle cell anemia. Spherocytosis: the loss of typical biconcave RBCs shape. I. Red Blood Corpuscles (Erythrocytes) morphologic features of RBCs: Anisocytosis: variation in RBCs size Normal: Mean corpuscular diameter = 6.7 - 7.9 microns (7.2). Variations: (Anisocytosis) Microcytes: small cells < 6.7 µ Macrocytes: large cells 8 - 12 µ Megalocytes: extremely large cells 12 - 25µ Schistocytes: small fragments 2 - 3 µ Poikilocytosis: variation in RBCs shape Normal: RBCs : Biconcave discs Variations: (Poikilocytosis) e.g. Sickle cells, Spherocytes , Ovalocytes  I. Red Blood Corpuscles (Erythrocytes) (C) R.B.Cs. Indices: 1- Hematocrit value [packed cell volume (PCV)] It is the volume of packed red cell relative to the total blood volume. Normal: Males 47 + 7 % Females 42 + 5 % Decrease in: Anemia Increase in: Polycythemia 2- Mean corpuscular volume (MCV) It is calculated as follows: Hematocrit value (PCV) x 10 No. of RBCs in millions/ mm3 Normal: 90 + 10 femtoliter (Fl) Increase in: Macrocytic anemia (pernicious, folic acid deficiency) Decrease in: Microcytic anemia (iron deficiency) I. Red Blood Corpuscles (Erythrocytes) (C) R.B.Cs. Indices:: 3- Mean corpuscular hemoglobin : (MCH) Hb concentration in gm/dl x 10 No. of R.B.Cs in millions / mm3 4- Mean corpuscular hemoglobin concentration (MCHC): Hb concentration in gm/dl x 100 hematocrit Average normal = 34% < 30% → Hypochromic anemia 30 - 33% → Normochromic anemia II- Hemoglobin concentration: Anemia Normal: Males: 15 ±12.5 mg/dl Females: 14 ± 12.5 gm/dl Polycythemia Children: (> 1 year) 13 ± 11.5 gm/dl (< 1 year) 12 ± 11.5 gm/dl  III- Total White Blood Cell count (WBC/mm3)  Neutrophils: 1st line of defense against bacterial and fungal infection. Eosinophils: Defense against parasitic infection and III- Total has role in allergic diseases. White Blood Basophils: Has a role in allergic diseases. Cell count Lymphocytes: (WBC/mm3) B-cell----plasma cells ----Ab production (Humoral immunity) T-cells ---------Cell-mediated immunity Monocytes: Change when reaching tissues into macrophages (Phagocytosis + antigen presentation)  In normal adults: 4,000- III- Total White 11,000/mm3 Blood Cell count (WBC/mm3) In children: slightly higher leukocytosis III- Total White Blood Cell count (WBC/mm3) a) In physiologic conditions: a) Decreased production: - Exposure to extreme temperature Due to Bone marrow depression - Exercise Aplastic anemia - Stress Iron deficiency anemia Cytotoxic drug administration b) In pathologic conditions: Metastases to bone marrow. Leukopenia - Infections (most cases) - Pancreatitis b) Increased destruction: - Drug induced (e.g. corticosteroids) Hypersplenism - Haemorrhage. Autoantibodies against WBCs (as in SLE) Bacterial infections as typhoid Viral infections as measles, HAV, HIV Protozoal infection as malaria III- Total White Blood Cell count (WBC/mm3) WBC Quantitative leukocytosis, disorders: (abnormal number) leukopenia (neutropenia, agranulocytosis Qualitative genetic diseases immunosuprresive (poorly functioning drugs cells) diabetes, HIV. malignancy IV. Differential white blood cell count Leukocyte type l Absolute Relative 1. Neutrophils Bands 0-2000/mm3 50-70% Segmented 3000-6000/mm3 2. Basophils 0-100mm3 0-1% 3. Eosinophils 100-700/mm3 1-3% 4. Lymphocytes 1000-4000mm3 20-35% 5. Monocytes 100-900/mm3 2-6% III- Total White Blood Cell count (WBC/mm3) 1. Neutrophils Decrease production as in: 1-Acute bacterial infection 1) Aplastic anemia Neutrophilia 2) cytotoxic drug therapy 2-Sterile inflammation (as that associated with tissue 3) B12 and folate deficiency necrosis in burns and 4) Idiopathic neutropenia myocardial infarction) Neutropenia 5) Bone marrow depression after irradiation. 3-Myeloid leukemia Increase destruction as in: 1-Hypersplenism. 2-Peripheral use ( overwhelming bacterial or fungal infections.) 3-Infection with some viruses III- Total White Blood Cell count (WBC/mm3) Lymphocytosis 2. Lymphocytes 1-Aplastic anemia 1-Chronic infections 2-Immunodeficiency Lymphocytopenia 2-Lymphocytic disorders leukemia Primary 3-Some viral infections Acquired (e.g. HIV infection ) e.g. mumps III- Total White Blood Cell count (WBC/mm3) Eosinophilia 3. Eosinophils Allergic disorders Aplastic anemia Parasitic infections Typhoid. Drug reactions Chronic Myeloid leu Eosinopenia  IV. Differential white blood cell count 4. Basophils Their increase is known as basophilia; It is a rare condition, occurs in chronic Myeloid leukemia. 5. Monocytes Increase ( monocytosis) Chronic infections (e.g. T.B) Decrease (monocytopenia) Infectious mononucleosis. Bacterial endocarditis Malaria Aplastic anemia Monocytic leukemia IV. Differential white blood cell count Leukocyte type l Absolute Relative 1. Neutrophils Bands 0-2000/mm3 50-70% Segmented 3000-6000/mm3 2. Basophils 0-100mm3 0-1% 3. Eosinophils 100-700/mm3 1-3% 4. Lymphocytes 1000-4000mm3 20-35% 5. Monocytes 100-900/mm3 2-6%  V. Platelets Count ( thrombocytes) Platelets function is mainly related to hemostasis: So both number and function are important. Normal platelet count: 150,000 - 500,000/mm3 Decrease in number = Thrombocytopenia (less than 150,000 /mm3) 20,000 - 50,000: Bleeding occurs only with trauma and surgery Less than 20,000: spontaneous bleeding may occur Less than 5,000: profuse spontaneous hemorrhage occurs. Increase in number = thrombocytosis or thrombocythemia (may reach 1,000,000 /mm3) Bleeding occurs with thrombocytosis due to abnormal function despite the increase in number.  V. Platelets Count Thrombocytopenia Idiopathic B12 and folate deficiency Secondary to drugs Secondary to diseases e.g. multiple myeloma. Hypersplenism Thrombocytosis Idiopathic Secondary to diseases as polycythemia Hemogram, complete bood count (CBC)  IV. Erythrocyte sedimentation rate (E.S.R.) It is the rate by which RBCs sediment to the bottom of a tube containing the patient’s citrated blood (Rouleau formation) It is non-specific, only indicating an active disease process (but not its nature) Used only for monitoring disease severity and response to therapy. Normal: Male: 2 - 7 mm ( 1 st hr.) Female:3 - 9 mm ( 1 st hr.)  Laboratory Investigations Asooc. Prof. Dr. Maha Abdelkawy Fahmy Oral Medicine and Periodontology Department Faculty of dentistry ,Beni-suef university 2nd lect  2- Tests for Haemostasis Three Mechanisms Cooperate in Haemostasis: 1- Blood vessel contraction and integrity 2- Platelets: adhesion, aggregation and release phenomena 3- The clotting cascade &Fibrinolytic system. Bleeding Tendency may Result From: 1) Increased blood vessels fragility (tested for by Hess test) 2) Platelet deficiency or dysfunction Tested for by a) Platelet count b) Platelet function analyzer c) Bleeding time d) Clot retraction 3) Coagulation mechanisms disorders Tested for by: a) Clotting time b) Prothrombin time (PT) c) Partial thromboplastin time (PTT) & activated partial thromboplastin time (APTT). d) Coagulation factors assays.  DENTAL EVALUATION Family HX Personal HX Medications Past & Present Illness Spontaneous Bleeding Observation of excessive Good thorough Physical Screening clinical bleeding medical history examination lab tests following surgical procedures Laboratory Investigations Related to Haemostasias & Blood Coagulation I. Testing Capillary Function Hess Test (Tourniquet test):  When the venous flow is obstructed, and the capillary walls are not normal, blood will get extravasated from the capillaries leading to petechial hemorrhage.  Technique: 10 petechiae means increased capillary fragility. Laboratory Investigations Related to Haemostasias & Blood Coagulation II - Testing Platelet Function 1 ) Platelet count: Hess test 2 ) Platelet function analyser (PFA)100) The PFA test result is dependent on: *platelet function *plasma *von Willebrand Factor level *platelet number, *the hematocrit. Laboratory Investigations Related to Haemostasias & Blood Coagulation II - Testing Platelet Function 1 ) Platelet count: Hess test 2 ) Platelet function analyser (PFA)100) Prolongation of test results:  Anemia (hematocrit 110 mg/dl and < 126 mg/dl = impaired fasting. FPG > 126 mg/dl =provisional diagnosis of DM.  2) Blood Glucose Level: c) Post-challenge plasma glucose (PCG) (2 hours after the administration of a standard 75 g oral glucose load) For the 2 hrs post-challenge glucose, sustained values > 200 mg/dl are considered diagnostic for DM. 3- Tests for d)Postprandial glucose (PPG) Diabetes (2 hours after the patient’s regular breakfast). Mellitus For the 2 hrs post-challenge glucose, sustained values > 200 mg/dl are considered diagnostic for DM. Categories of 2 hours post-prandial glucose (2h PPG) include: 2h PPG < 140 mg/dl = normal glucose tolerance. 2h PPG > 140 mg/dl and < 200 mg/dl=impaired glucose tolerance. 2h PPG > 200 mg/dl = provisional diagnosis of DM.  3- Tests for Diabetes Mellitus 2) Blood Glucose Level: c) Post-challenge plasma glucose (PCG) (2 hours after the administration of a standard 75 g oral glucose load) For the 2 hrs post-challenge glucose, sustained values > 200 mg/dl are considered diagnostic for DM. d)Postprandial glucose (PPG) (2 hours after the patient’s regular breakfast). For the 2 hrs post-challenge glucose, sustained values > 200 mg/dl are considered diagnostic for DM. d)Postprandial glucose (PPG) (2 hours after the patient’s regular breakfast). Categories of 2 hours post-prandial glucose (2h PPG) include: 2h PPG < 140 mg/dl = normal glucose tolerance. 2h PPG > 140 mg/dl and < 200 mg/dl=impaired glucose tolerance. 2h PPG > 200 mg/dl = provisional diagnosis of DM.  3- Tests for Diabetes Mellitus 3) Glucose Tolerance test: It is an accurate method for detection of the response of the pancreas to a measured oral or I.V. dose of glucose. Advantages: 1 ) Detects patients prone to develop diabetes ( border line patients) 2 ) It can differentiate between diabetes mellitus and other causes of high glucose level as hyperthyroidism. Disadvantages: 1 ) Time consuming (2 - 3 hrs). 2 ) Expensive ( 5 readings of blood glucose level). 3 ) Exhausting for the patient.  3- Tests for Diabetes Mellitus 3) Glucose Tolerance test: Procedure: 1 ) 3 days of unrestricted (high carbohydrate ) diet + physical exercise. 2 ) 10 - 16 hours of fasting (nothing except water). 3 ) Fasting blood sample is taken. 4 ) A measured dose of glucose is administrated either: Orally : 75 gm glucose in solution or I.V. : 0.5 mg glucose /kg body wt. 5) Blood samples are taken at ½ hour intervals for 2-3 hours, thus giving 5 - 7 samples: But usually: ½ hr, 1 hr , 2 hr , then 3 hr. samples are taken.  3- Tests for Diabetes Mellitus Normal Results: Fasting = ~ 100 mg /dl. ½ hr. = 120- 160 mg / dl. 1 hr. = 160 mg /dl. 2 hr. =