Wk 3: Hematology Flashcards
1) Define CBC
2) Is it easy to do?
1) Series of tests of the blood that provides information about RBCs, platelets, and WBCs
2) Easy, quick, inexpensive
What are included in a CBC?
1) RBC
2) Hemoglobin
3) Hematocrit
4) Platelets
5) RBC indices: MCV, MCH, MCHC, RDW
6) WBC count
6) CBC with diff.: differential WBC
(i.e. the five white blood cell types:neutrophils, lymphocytes, monocytes, eosinophils, and basophils.)
1) What 3 things does a blood smear include?
2) Is it on the CBC?
1) WBC, RBC, PLT
2) Not on CBC
What is the reference range for erythrocyte count (RBC)s?
[don’t need to memorize]
Male: 4.7 – 6.1; female: 4.2 – 5.4 (x1012/L)
1) What does RBC count?
2) Describe the general population/ demographic trends in RBC count
1) Measures the number of RBCs in 1mm3 of peripheral blood
2) Females have lower values than males and RBC count decreases with age
What is a decreased RBC count called?
Anemia
List 3 categories of conditions that can cause anemia (decreased RBCs) and give examples of each
1) Conditions that decrease production by bone marrow
-Myelofibrosis, leukemia, renal disease, dietary deficiencies
2) Conditions that involve increased loss
-Hemorrhage, hemolysis
3) Dilution of body fluids
-i.e., pregnancy, overhydration
Too many RBCs is called what?
Polycythemia
1&2) List 2 potential causes of polycythemia and give examples.
3) What may factitiously increase RBCs?
1) Physiologically induced due to increased O2 requirements
-i.e., living at high altitudes
2) Chronic hypoxia
-i.e. COPD
3) Dehydration factitiously increases
List 3 subgroups of anemia and their causes
1) Macrocytic anemia: Megaloblastic anemia
2) Microcytic anemia: Small RBCs
3) Pancytopenia: Aplastic anemia
1) What is Megaloblastic anemia?
2) What does it result in?
3) What are some potential causes?
1) DNA synthesis impairment during RBC production
RBCs continue growing without dividing
2) Larger RBCs but fewer of them
3) Many causes but usually Vit B12 or folate deficiency
(Folate = natural B9; folic acid = synthetic B9)
1) Define microcytic anemia
2) What is the most common cause?
3) What are some common roots of that cause?
4) What happens if stored iron is eventually depleted?
1) Small RBCs
2) Many causes, Fe intake is most common cause
*don’t assume it’s Fe just bc it’s the most common
3) Insufficient intake, increased need, insufficient absorption, or increased blood loss
4) Hgb drops.
True or false: you can assume the cause of microcytic anemia is reduced Fe intake
FALSE (!!)
What does pancytopenia include?
Leukopenia, anemia, thrombocytopenia
1) What is the most common cause of pancytopenia?
2) What is pancytopenia?
3) List some conditions that can cause this
1) Aplastic anemia most common cause
2) Deficiency of all blood cell types
3) Toxin exposure, hereditary, autoimmune disorder. Often idiopathic.
What is the most common cause of aplastic anemia?
Cancer
Retic count/ reticulocytes:
1) What is it?
2) What is the reference range?
1) Percentage of immature RBCs
2) Reference range in adults: 0.5% - 2.0%
1) Increased retic count indicates what?
2) What are the causes of this consistent with?
3) What does the body do to cause this?
1) Indicates that marrow is putting more RBCs into circulation
2) Causes consistent with ongoing loss of RBCs (hemolysis, hemorrhage)
3) Body attempts to compensate by increasing RBC production, which pushes out immature RBCs “retic-ing”)
1) Low (or even normal) retic count in patient with anemia indicates what?
2) If anemia is still present, bone marrow should be doing what?
3) Give 2 potential causes
1) Inadequate bone marrow response to the anemia
2) Correcting it or pushing out retics trying to correct it
3) Chemotherapy, aplastic anemia (body stops producing new blood cells)
Hemoglobin (Hgb)
1) What are the reference ranges? [don’t need to memorize]
2) What are critical values?
3) What is hemoglobin?
1) Male: 14-18; female: 12-16 g/dL
2) Less than 5 or greater than 20
3) RBC protein that carries oxygen (and CO2)
1) What does hemoglobin (Hgb) reflect?
2) Increased and decreased levels of Hgb point to what?
3) What is low hemoglobin also called?
1) The number of RBCs in the blood
2) Similar causes as RBCs
3) “Anemia”
Hematocrit (Hct):
1) What are the reference ranges?
2) What are critical values?
[don’t need to memorize]
1) Male: 42-52%; female: 37-47% /“crit”
2) Less than 15% or greater than 60%
1) What is hematocrit (Hct)?
2) What does it closely reflect?
3) Compare it to Hgb values
1) Percent of total blood volume made up of RBCs
2) Closely reflects RBC values
3) Normally 3x Hgb value
1) Altered hematocrit (Hct) values reflect what?
2) Extremely elevated ___________ can decrease Hct
1) Same pathologic states and are affected by hydration in the same manner
2) WBC
Platelet Count (Plt):
1) What are the reference ranges?
2) What are critical values?
[don’t need to memorize]
1) 150,000-400,000/mm3
2) Less than 50k or greater than 1 million
1) What is platelet count?
2) What are platelets essential for?
1) Number of thrombocytes per cubic mm
2) Blood clotting
Decreased platelets is called what?
Thrombocytopenia
What are some causes of thrombocytopenia?
1) Reduced production (bone marrow failure, cancer)
2) Hypersplenism sequestration (platelets trapped in spleen)
3) Increased destruction (antibodies, infections, drugs, prosthetic heart valves)
4) Consumption (DIC)
5) Hemorrhage
Differentiate between thrombocytosis and thrombocythemia
1) Thrombocytosis: pt is making too many platelets
2) Thrombocythemia: pt has too many platelets
Give 3 potential causes of thrombocythemia
1) Iron deficiency anemia
2) Cancer
3) Various hematologic conditions
1) Define Mean Platelet Volume (MPV)
2) What is the mechanism that effects this?
3) Which are larger, immature platelets or mature?
1) Measurement of the average size of platelets
2) Bone marrow will release immature platelets to maintain normal count
3) Immature platelets are larger (“reticulated platelets”)
What are 2 potential causes of increased MPV (larger average platelets)?
Massive hemorrhage, leukemia
1) Decreased MVP indicates what?
2) Give 3 potential causes
1) Bone marrow underproducing platelets, fewer immature platelets too
2) Chemotherapy, myelosuppression, aplastic anemia
Red Blood Cell Indices provide what info? (3 things)
Size of RBCs, their hemoglobin content, and the concentration of hemoglobin
Red Blood Cell Indices:
1) What are the 3 categories of cell size?
2) What are the 3 categories of hemoglobin content?
3) What are the 4 RBC indices?
1) Normocytic, microcytic, macrocytic
2) Normochromic, hypochromic, hyperchromic
3) MCV, MCH, MCHC, RDW
1) What is Mean corpuscular volume (MCV)?
2) What is it useful for?
3) What may cause it to increase? What is this called?
4) What may cause it to decrease? What is this called?
1) RBC version of MPV; average size of RBCs
2) Useful in classifying anemias.
3) Increased MCV (macrocytic): Megaloblastic anemias like B12 or folic acid deficiency
4) Decreased MCV (microcytic): Iron deficiency anemia or thalassemia
1) What is Red blood cell distribution width (RDW)?
2) What is it useful for?
1) Variation of RBC sizes in the sample
2) In classifying anemias
If a pt has an increased MCV what do you need to test next?
For B12 or folic acid deficiency
True or false: you cannot assume that microcytic anemia is an iron issue
True (could also be thalassemia)
Red blood cell distribution width (RDW) will be ________ if a pt is hemorrhaging
high
1) What is Mean corpuscular hemoglobin (MCH)?
2) ____________ cells have more Hgb than __________ cells so values consistent with MCV
1) Average amount of hemoglobin in an RBC
2) Macrocytic; microcytic
1) What is Mean corpuscular hemoglobin concentration (MCHC)?
2) What words mean high or low MCHC?
1) Average concentration of Hgb in 1 RBC relative to volume of the cell
2) Hypochromic RBCs and hyperchromic RBCs
1) What may cause hypochromic RBCs?
2) What may cause hyperchromic RBCs?
3) What indice is this related to?
1) Hgb deficiency
2) Probably a machine error or hemolyzed sample; could indicate altered RBC shape which allows them to fit more Hgb
3) MCHC
Would MCHC be high or low with macrocytic anemia?
Low; because there’s more space inside the cells
What are the two components to the leukocyte portion of the CBC?
1) WBC count
2) WBC differential
WBC count (reference range: 5,000-10,000/mm3) “white count” “5”:
1) What are the critical values?
2) What is it used for?
1) Critical values: less than 2,500 or greater than 30,000
2) Routinely used to diagnose and track infections
1) What may cause increased WBC count? (leukocytosis)
2) What may cause decreased WBC count? (leukopenia)
1) Infection, inflammation, cancer, leukemia, necrosis
-Trauma, emotional stress, physical stress, pain
2) Bone marrow failure, cancer treatment, autoimmune diseases, cancer
-Overwhelming infections
1) What does leukocytosis mean?
2) What abt leukopenia?
1) High WBC count
2) Low WBC count
True or false: in real life WBC does not guarantee infection. Explain.
True; typically an assumption on assessments
1) What is the White Blood Cell Differential?
2) What do neutrophils (55-70%) do and what do increased values indicate?
1) Percent of each type of leukocyte
2) Phagocytize bacteria. Increased values indicate bacterial infection.
1) What lymphocytes does a WBC differential combine?
2) What do high lymphocytes indicate?
1) T and B lymphocytes
2) Chronic bacterial or acute viral infections
Significant production of neutrophils can lead to what? What is this called?
Immature neutrophils; bands
Explain left shifts and right shifts
1) Significant WBC production can lead to immature neutrophils = bands; this is called “left shift” and represents an ongoing bacterial infection
2) “Right shift” represents return towards normal values
True or false: you can’t see bands with a typical CBC, you need to add on to the order
True
1) What do monocytes (2-8%) do?
2) What is unique about them?
1) Fight bacteria like neutrophils
2) Remain in circulation longer and are produced more rapidly
1) Eosinophils (1-4%) and basophils (0.5-1%) represent what?
2) What might basophilia on its own indicate?
1) Represent a response to parasite or allergens
2) Leukemia
True or false: basophils and eosinophils do not respond to bacterial or viral infections
True
1) Is a blood smear a part of CBC? Explain
2) What is it?
3) When is it often done?
1) Part of the CBC-ordered separately
2) Manual microscopic examination of RBCs, platelets, and WBCs by pathologist or technician
3) When automated cytometer detects abnormal values
Blood smear verifies what?
1) Quantities of RBCs, platelets, WBCs
2) Size, shape, color of RBCs
3) Size and granulation of platelets
4) WBC counts
List and define 3 WBC inclusions and when they’re seen
1) Hypersegmented neutrophils: Neutrophils with 6 or more lobes
Highly sensitive and specific for megaloblastic anemias (B12/folic acid deficiency)
2) Dohle bodies: Oval inclusions due to severe stress (like burns) causing improper maturation
3) Auer rods: Acute myeloid leukemia
1) Define leukemia
2) What are the 2 categories?
1) WBC cancer in the blood
2) Divided into acute and chronic
Chronic leukemia:
1) What makes it different from normal leukocytes?
2) What is the presentation?
1) Difficult to tell from normal mature leukocyte except that there are many
2) Presentation is asymptomatic with severely elevated WBC
Differentiate chronic myeloid leukemia (CML*) and chronic lymphocytic leukemia (CLL)
1) CML: Elevated PMNs (neutrophils, eosinophils, basophils, mast cells)
2) CLL: Elevated lymphocytes only
1) What is the next step in diagnosing CML or CLL?
2) What do CML and CLL have in common?
1) Bone marrow biopsy
2) Both geriatric cancers
Acute leukemia:
1) What is it?
2) What are the Sx/ presentation?
3) What is the next step after CBC?
1) Blast cells (type of immature WBC) cause bone marrow dysfunction
2) Infections and fever (no WBCs), anemia (no RBCs), bleeding (no platelets), bone pain
3) Bone marrow biopsy
Acute leukemia:
1) What would elevated PMNs indicate on a blood smear?
2) What about elevated lymphocytes?
1) Acute myeloid leukemia (AML)
2) Acute lymphoBLASTIC leukemia (ALL)
Acute lymphoblastic leukemia (ALL) is more common in _____________ whereas acute myeloid leukemia (AML) is more ________________ (but the other group can get it too)
pediatrics; geriatric
1) What are lymphomas?
2) There are many subtypes, but what are the 2 main categories?
1) Cancers arising from lymphocytes
2) Non-Hodgkin’s lymphoma (NHL) and Hodgkin’s lymphoma (HL)
1) Why is distinction between the two categories of lymphoma important?
2) What are the 2 categories? What % is each?
1) Distinction is important because their treatments are effective but only if correct type is identified
2) Non-Hodgkin’s lymphoma (NHL) 90%
*Hodgkin’s lymphoma (HL) 10%
Which type of lymphoma does this describe? “Marked by the presence of Reed-Sternberg cells on biopsy. Mutated B-cells with “moth-eaten” appearance”
Hodgkin’s lymphoma
1) Iron Panel consists of what?
2) Abnormal serum iron levels are characteristic of many diseases including what?
1) Serum iron, TIBC/transferrin, transferrin saturation, and ferritin (often separate)
2) Iron deficiency anemia and hemochromatosis
____% of iron is in Hgb of RBCs, remaining ______% stored as ferritin (and hemosiderin)
70%; 30%
1) What is Total iron binding capacity (TIBC) /transferrin?
2) What does a high TIBC indicate?
1) Measurement of all proteins available for binding iron (mostly transferrin)
2) Iron deficiency
1) Transferrin saturation tells you what?
2) When is it decreased?
3) When is it increased?
1) Percentage of TIBC (mostly transferrin) that is saturated with iron
2) Iron deficiency anemia
3) Increased in other anemias, iron overload, or poisoning
1) What is ferritin?
2) What does serum ferritin represent?
1) Major storage protein for iron
2) Serum ferritin represents iron stores in the body
1) What does decreased ferritin do to iron stores? Explain.
2) what does increased ferritin represent? Explain/ give examples
1) Decreased ferritin represents depleted stores; Iron deficiency anemia
2) Iron excess: Iron overload, recent blood transfusion, hemosiderosis, hemochromatosis, anemias, hepatitis (and some anemias)
1) Ferritin can be factitiously elevated in chronic disease states; why?
2) Give examples
1) Positive acute phase reactant (serum concentration rises significantly with inflammation)
2) Cancer, infection, liver disease, alcoholism
Total iron in body is equal to what two things put together?
Ferritin (stored iron) + TIBC (transferrin)
Balance of iron-out vs iron-in:
1) Too much iron-out causes what?
2) Too much iron-in causes what?
Balance of iron-out vs iron-in
1) Ferritin decreases, TIBC increases
2) Ferritin increases, TIBC decreases
1) What is Erythrocyte Sedimentation Rate (ESR)?
2) Describe why increased sedimentation rate is a sign of inflammation
1) The rate at which RBCs settle
2) Proinflammatory conditions (infection, cancer, necrosis) increase protein content for plasma (positive acute phase reactants)
-Pushes RBCs closer together, which causes them to stack
-Stacks of RBCs settle more rapidly than single RBCs
1) What can ESR be used for?
2) How should it be applied irl?
3) When is it ordered?
1) Can be used to detect or track inflammation
2) Focus on the trend, not one number
3) Frequently ordered to detect presence of infection but is very nonspecific
1) C-reactive Protein (CRP) is commonly ordered with what?
2) What is this protein? Is it specific?
3) When does it not rise consistently?
1) ESR
2) Acute phase reactant protein secreted by liver in the presence of inflammation or bacterial infections; nonspecific
3) With viral infections
CRP is more sensitive to ESR and responds more quickly; disappearance of _______ precedes __________ returning to normal
CRP; ESR
1) What is CRP used to determine? Why?
2) What is the disadvantage of using CRP?
1) Cardiac risk factors (elevated: 3xs increased risk MI)
2) Many causes for elevated CRP
Give examples of the many causes for elevated CRP
HTN, increased BMI, DM, low HDL, high triglycerides, smoking, chronic gingivitis
1) What is a Coagulation Panel?
2) What is it commonly ordered with?
3) What does it include? (4 things)
1) Combination of tests used to provide broad understanding of hemostatic mechanisms
2) Commonly ordered with CBC (platelets esp important) and LFTs (covered later)
3) Bleeding time, PT/INR, PTT, Fibrinogen
1) Bleeding time: what is it?
2) What does increased time indicate?
1) Causing superficial puncture wound and blotting skin every 30sec until it stops bleeding
-Normal time depends on specifics of method.
2) Platelet dysfunction.
1) What is prothrombin made by? What is it?
2) What does protime/prothrombin time (PT) tell you?
1) Liver; the inactive form of thrombin which turns fibrinogen into fibrin
2) Time it takes for blood to clot via extrinsic clotting pathway; factors 1, 2, 5, 7, 10
Decrease in factors [affecting PT] can be due to many causes; list 3 and explain why for each
1) Liver disease (affects production)
2) Obstructive biliary disease (affects bile secretion which is needed for fat soluble Vit K which is needed for factors 2, 7, 9, 10)
3) Anticoagulant administration (warfarin)
1) International normalized ratio (INR) is calculated from what? Why?
2) Target INR varies depending on what?
3) What is it essentially a measure of?
4) What is the INR reference range? [don’t need to memorize]
1) Calculated from PT in order to assess risk of bleeding/coagulation
2) Condition being treated
3) How much longer it takes for blood to clot
-1.5 = 50% longer for blood to clot (blood is “thinner”)
4) 1.0-1.3
True or false: PT and INR communicate the same thing
True
If INR is 5 (aka high) what does that mean?
Their blood is too thing, taking too long to clot
1) Partial thromboplastin time (PTT) measures what?
2) What factors are involved?
1) Speed of blood clotting via intrinsic pathway
2) 8, 9, 11, 12
1) Fibrinogen assay measures what? What is this?
2) When is it decreased? (3 scenarios)
1) Factor I; common pathway factor
2) Liver disease, consumptive coagulopathy, recent transfusion (banked blood does not have fibrinogen)
Fibrinogen assay:
1) When is it positive (acute-phase reactant)?
2) What 4 things is fibrinogen assay also associated with?
1) Bleeding disorders & Inflammation or necrosis
2) CAD, stroke, MI, PAD
1) PT/INR vs PT can help identify what?
2) What factor(s) would be altered if only PT was affected?
1) Which factors are deficient and associated conditions
2) 7 (plus 1,2, 5, 10 to lesser extent; extrinsic plus common pathways)
1) What factors are measured in PTT only?
2) What abt in both PT and PTT?
1) PTT only: 8, 9, 11, and 12
2) PT and PTT: 1, 2, 5, and 10
1) D-dimer is produced by what?
2) When do levels increase? Give examples.
3) What is it useful in?
1) Degradation of fibrin
2) Levels increase when a clot is degrading and therefore elevated d-dimer increases suspicion of a clot in the body (DVT, PE)
-Cancer, inflammation, infection, COVID-19; sickle cell disease (sickle cells make fibrin resistant to fibrinolysis)
3) Screening for DVT before sending patient for ultrasound
Why should you be hesitant to order a D-dimer?
Extremely sensitive (essentially 100%) for clots but notoriously nonspecific.
(i.e. you will get sued if you don’t pursue an elevated d-dimer)
