Laboratory Medicine

kukuhkjhh's version from 2017-02-12 22:35

Section 1

Question Answer
What determines how test rests are reported ?lab organization determines how test results are reported
What are lab results segregated into ?chemistry or hematology
What is panel testing ?group testing run on sequential anazlyers / named by instrument or number of tests
What are panel tests intended to focus on ?intended to focus on organ system ( liver, cardiac)
What are the 4 purposes of lab testing ?1. to monitor organ and metabolic function 2. to establish the presence and follow the course of a disease process 3. to establish etiologies 4. to establish identities
What is the purpose of lab testing (2)?1. to CLASSIFY subjects with or without a characteristic (blood type, HLA) 2. to QUANTIFY an analyte known or suspected to be present (Glucose, liver enzymes)
What is normal in lab medicine ?There are NO standard "normals", reference values vary
How do you determine normal lab results ?each lab is responsible for establish and publishing its normal values for the population serves and the person ordering the test is responsible for knowing these values
When interpreting lab results what detrmines diagnosis and indicates a threatening situation mandating immediate treatment "high" , "low" or "critical value" determines diagnosis ...
What is sensitivity ?a positive test result for the disease the test is intended to reveal ( a "true" positive)
what is specificity ?a negative test result for the disease that the test is intended to reveal (a "true" negative )
What is a positive predictive value ?probability that a patient with a positive test result actually has the disease
what is a negative predictive value ?probability that a patient with a negative test does not have the disease
What are the 4 medical considerations in dentistry ?1. risk of infection 2. risk of bleeding 3. drug interactions and actions 4. risk of acute medical emergency in dental office

Section 2

Question Answer
What is red vacutainer?chemistry , type and cross, serology
What is blue vacutainer?coags
What is purple vacutainer?hematology
What is green vacutainer?cortisol, ammonia, Ca++
What is gray vacutainer?lactic acid

Section 3

Question Answer
What are the 5 white blood cells ?1. neutrophils 2. lymphocytes 3. monocytes 4. eosinophils 5. basophils
What are the 3 elements of blood ?1. RBC 2. WBC 3.platelets
Where do myeloid stem cells and lymphoid stem cells come fromPleuripotent stem cells
What do myeloid stem cells form ? (4)1. RBC 2. platelets 3. granulocytes and 4. monocytes
What does lymphoid stem cells form (2)?1. lymphocytes 2. plasma cells
What does a CBC (complete blood count) consists of ? (9) 1. hemoglobin (Hgb) 2. Hematocrit (Hct) 3. red cell count (RBC) 4. Meant corpuscular volume (MCV) 5. Mean corpuscular hemoglobin (MCH) 6. Mean corpuscular hemoglobin concentration (MCHC) 7. red blood cell distribution width (RDW) 8. platelet count (Plt) 9. white cell count (WBC)
What is the mean red blood cell count ?4.7-6.6 x 10 ^6/mm3
What is the fair (F) red blood cell count ?4.2-5.4 x 10^6/mm3
What is a high RBC called ?polcytehmia vera (primary and secondary )
what is the low RBC called ?anemia
What is anemia ?a reduction the oxygen carrying capacity of blood (resulting from a decreased conc. of hemoglobin contained within RBCs) or (resulting from a decreased # of circulating RBCs)
What is the mean hemoglobin ? what is the fair (f) hemoglobin? mean: 14-18 gm/dl and Fair: 12-16 gm/dl
What is it called if you have low hemoglobin? high hemoglobin?high: polycythemia vera / lowanemia
What is the mean hematocrit? what is fair hematocrit ?mean: 42-54% fair: 37-47%
What is it called if you have low hematocrit? high hematocrit ?High: polycythemia vera / Low: anemia
What is hematocrit ?the volume of packed erythrocytes per 100mL of blood
What is the mean corpuscular volume ?the average volume of RBCs /// the ratio of hematocrit to RBC count ///// it is NOT equal to the high or low hematocrit
what is the of the mean corpuscular volume (MCV) ?range: 90+/-7 fl
What is it called if you have a HIGH MCV ? LOW MCV(mean corpuscular volume)?High= macrocytosis / Low= microcytosis
What is the mean corpuscular hemoglobin?average weight of Hgb contained in a RBC
What is the range of the mean corpuscular hemoglobin?29+/-2pg
What is it called if you have high MCH? low MCH(mean corpuscular hemoglobin)?High= hyperchromia / Low= hyochormic anemia
What is the mean corpuscular hemoglobin concentration (MCHC)?the average concentration of hemoglobin in a given volume of RBCs
What is the range of MCHC (mean corpuscular hemoglobin volume)? 34+/-2gm/dl
What is a high MCHC (mean corpuscular hemoglobin concentration) called ?what is a low MCHC called ?high: hereditary spherocytosis Low: hypo chromic anemia
What ist he red blood cell distribution width?A description of the regularity of cell diameters // measured by the coulter counter /// stand. dev. of RBC size/MCV
What is the range of the red blood cell distribution width?11.8-14.1%
What happens to the red blood cell distribution width (RDW) during anemia ?it is increased in anemias
What is anisocytosis ?variation in RBC size
Is the Red blood cell distribution width a low %? Never low, either normal or high
What is the erythrocyte sedimentation rate (ESR) ?a non-specific test that measures the rate at which anti-coagulated blood forms rouleau
What is a normal erythrocyte sedimentation rate ? 20mm/hr
what happens the ESR (erythrocyte sedimentation rate) during disease/inflmmation?it is increased with disease/inflammation
What is the platelet count?thrombocytosis vs. thrombocytopenia
*****What is the range for the platelet count ?150,000 - 400,000 cells/mm3
What does it mean if you have a high platelet count ?inflammatory reactions, blood d/o, malignancy , post-splenectomy
what does it mean if you have a low platelet count ?immune/idiopathetic , viral diseases , SLE, drugs
***What does it mean if you have below 60,000 platelets ?increased risk of clinical bleeding
***what does it mean if you have below 20,000 platelets ?spontaneous bleeding
****What is the range of white blood cell count?4,500-11,000/mm3
What does it mean if you have a HIGH white blood cell count?infection, malignancy
what does it mean if you have LOW white blood cell count?neutropenia, hematologic neoplastic disease, drugs, viral infection

Section 4

Question Answer
What is a peripheral blood smear for ?gives info on size and shape of RBC
What will a peripheral blood smear allow for ? (3)1. ID of sickle cell anemia 2. normocytic, microcytic and microcytic anemia 3. normochromic or hypochrmoic anemia
What is leukocytosis ? elevated white blood cells count
What are physiologic causes for leukocytosis ? (3)1. extreme temperature 2. muscular activity 3. pregnancy
What are the pathologic reasons for leukocytosis ?1. infection 2. tissue death 3. allergy 4. leukemia 5. inflammation 6. cancer
What is leukopenia ?low white blood cell count
What are 5 causes of leukopenia ?1. megaloblastic anemias 2. diurnal or familial variation 3. bone marrow depression 4. malignant neutropenia or myeloproliferative syndromes 5. viral infections (influenza)
what is the largest cell % of WBCs?neutrophils 50-70 % / 3,000-7,000
What is the % of WBCs that are lymphocytes ?20-40% (1,000-3,500)
what % of WBCs are monocytes ?0-7% (0-700)
What % of WBCs are eosinophils ?0-5% (0-500)
What % of WBCs are basophils ?0-1% (0-100)
What tells you the age of neutrophils ?nuclear lobulation gives indication of cell age
What is the indicator that a neutrophil is mature? What is the indicator that a neutrophil is NOT mature ?segs= mature /// bands = immature
What does a LEFT shift in neutrophils mean?increased immature PMNs (1-2 lobes) /// >20% bands or segs and bands //// >80% of total WBC
what does RIGHT shift in neutrophils mean?increased mature PMNs (4 lobes)
What does a left shift in neutrophils indicate?acute bacterial infection, physical/emotional stimuli, toxemia, hemorrhage , leukemia, diabetes
What does a right shift in neutrophils indicate ?chronic inflammation, autoimmune disease, megaloblastic anemia, iron deficiency
What is neutropenia ?a mild decrease in PMNs
What is agranuloyctosis ?severe decrease of PMNs
When would you do an antibiotic prophylactic due to PMN count ?Ab prophy when below 500 cell/mm3
What 6 conditions would warrant an AB prophy due to low PMNs? 1. metastes/cancer 2. connective tissue diseases 3. hereditary 4. drugs 5. radiation 6. leukemia

Section 5

Question Answer
What is the purpose of the serum electrolyte lab analysis ?organ and metabolic function
What are the 2 methods for organ and metabolic functions ?1. measures an elaborated product (i.e. hormone, protein) 2. measures the elimination of a waste material
What will organ and metabolic function tests tell us?these tests can only describe without telling weather the failure is the restful of continuos injury or the result of terminal destruction
What does the "chemistry 7" panel test for ?1. sodium 2. chloride 3. potassium 4. CO2 5.blood urea nitrogen 6. creatinine 7. glucose
What 3 inorganic ions do we test for ?1. calcium 2. magnesium 3. phosphorous
What is the normal range for sodium?135-145 mEq/I
**What is high sodium called ?Hypernatremia (excess water loss)
****What does hypernatreamia cause ?Hypernatreima (high sodium ) = excess water loss, vomiting , diarrhea
What is low sodium called ?hyponatrermia
What does hyponatremia cause ?CHF, arenal insufficiency and excess use of diuretics
What is the range of chloride ?980106 mEq/I
**What does high chloride cause ? low chloride cause ?High= excess water loss, vomiting, diarrhea /// LOW= Committing (
What will cause bulimia (2)?HIGH sodium // LOW chloride
What is the range for potassium ?3.5-5 mEq/I
What is it called if you HIGH potassium?LOW potassium ?HIGH=hyperalkemia // LOW= hypoalkemia
What does hyperalkemia (high potassium )) cause ?renal failure, acidosis , crush injuries
What does hypoalkemia (low potassium) cause ?poor intake, vomiting , diarrhea
What is the range for CO2?21-30 mEq/I
What does high CO2 mean ?metabolic ALKALOSIS, respiratory ACIDdosis
what does low CO2 mean ?metabolic ACIDOSIS , respiratory ALKALOSIS
What is the range for blood urea nitrogen?Range: 10-20mg/dl
What does high BUN mean ?azotemia, decreased GFR, renal failure
What does low BUN mean ?ESLD , malnutrition
What is creatinie ?metabolic byproduct in muscle
How much creatinine is excited by the kidneys?100% excited by kidney
What does a HIGH creatinine level mean ?severe muscle disease , renal impairment
What is a normal range of glucose ?70-1110 mg/dl
What does high glucose indicate?DM, pancreas removal, Cushing's, glucocorticosteroid therapy, pheochromocytoma
What does low glucose indicate?hepatic disease, Addison's disease, excess insulin, insulin-secreting tumors, ESLD, pituitary hypo function
What is the range of calcium?9-10.5mg/dl
What does high calcium mean?Vit K excess, lytic/ metastic bone tumors, hyperparathyroidism , sarcoid , TB
What does low calcium mean?hypoparrahyroidism, vit. D deficiency, renal failure
What is the normal range of magnesium?1.3-2.1 mEq/I
what does high magnesium indicate ?renal failure, excess antacids
What does low magnesium indicate?alcoholism, malabsorption, diabetic acididos
What is the range of phosphorous ?3.4-5mg/dl
What is low phosphorous ?hyperparathyroidism, increased carb metabolism
What is high phosphorous ?renal disease, hypoparathyroidism, healing bone fractures, increased growth hormone
What doe triglycerides and cholesterol tell us risk factor for CAD , HTN
What is the range for triglycerides ?30-170 mg/dl
What is the range for cholesterol ?120-200mg/dl

Section 6

Question Answer
What does creatinine phophkinase (CPK) tell you?*peaks at 24h following MI, returns to normal in 3-4 days
***** What isoenzyme is cardiac mm specific ?MP isoenzyme (troponin) !! is cardiac mm specific
What does lactate dehydrogenase (LDH) tell you ?peaks 3-6 days following MI, returns to normal 8-14days later
When will alanine aminotransferase (ALT) tell you?only elevated with accompanying liver disease or CHF
What does an increased total of creatine phophokinase tell you ?MI , mm necrosis , CVA or hypothyroidism
What is greater in viral hepatitis ?ALT 10x > AST in viral hepatitis
What is greater in alcohol related liver disease?AST > ALT in alcohol related liver disease
T/F liver enzymes = liver function FALSE
What is the best test to assess liver function ?INR
What do liver enzymes correlate to ?only related to destruction of liver cells
What do B-cell lymphocytes make antibodies out of ?make Abs out of proteins
What does it mean if you are malnourished ?you are immunosuppressed

Section 7

Question Answer
What are the main renal function tests ?1. BUN and 2. serum creatinine