Hematolgy I - DONE Flashcards
What is hematocrit?
Percentage of whole blood that is comprised of red blood cells
- HCT (%) = MCV(fL) x RBC(mln/µL) / 10
- Reference ranges: 26-50%
What is hematocrit used for?
- Identify and evaluate the severity of anemia (low RBCs, low hemoglobin, low hematocrit) or polycythemia (high RBCs, high hemoglobin, high hematocrit)
- Monitor the response to treatment of anemia or polycythemia and other disorders that affect RBC production or lifespan
- Help make decisions about blood transfusions or other treatments if anemia is severe
- Evaluate dehydration
MCV =
Mean Corpuscular Volume
What is Mean Corpuscular Volume (MCV)?
A measurement of the average size of a single red blood cell
- MCV (fL) = HCT (%) x 10 / RBC (mln/µL)
- Reference ranges: 80-96 fL (depends on age)
What is the factor 3 rule?
Physiologically RBC count, hemoglobin and hematocrit are related to one another by a factor 3
- RBC (x10^6/ul)x3=Hemoglobin (g/dL)
- Hemoglobin (g/dL)x3= Hematocrit (%)
MCH =
mean corpuscular hemoglobin weight
What is Mean Corpuscular Hemoglobin weight (MCH)?
A calculation of the average amount of hemoglobin inside a single red blood cell
- Reference ranges: 26-38 pg
- MCH = HGB (g/dL) x10 / RBC (mln/µL)
MCHC =
Mean Corpuscular Hemoglobin Concentration
What is Mean Corpuscular Hemoglobin Concentration (MCHC)?
A calculation of the average concentration of hemoglobin inside a single red blood cell
- Reference ranges: 31-37 g/dL
- MCHC = HGB(g/dl) x100 / HCT(%)
What does high MCHC indicate?
High MCHC is indicative for hereditary spherocytosis
What is indicative for hereditary spherocytosis?
High MCHC is indicative for hereditary spherocytosis
What is the maximal value of MCHC? And what does higher values than that indicate?
Maximal value 38 g/dL
- higher values are indicative for autoimmune hemolytic diseases
- a CBC should be measured in warm (37C) sample
RDW =
red blood cells distribution width
What is red blood cells distribution width (RDW)?
a calculation of the variation in the size of RBCs
- RDW CV (%) = SD x 100% / MCV
- RDW SD (fL) = MCVmax – MCVmin
What is anisocytosis?
Variable size of red blood cells is called
What are reticulocytes?
Immature red blood cel with network of ribosomes and endoplasmic reticulum
- Reference ranges: 0.5-1.5%
ESR =
Erythrocytes sedimentation rate
What is Erythrocytes sedimentation rate (ESR)?
the rate at which red blood cells sediment in a period of one hour
What results in elevated Erythrocytes sedimentation rate (ESR)?
If the ESR is elevated, it is typically a result of two types of proteins, globulins or fibrinogen
What can can increase Erythrocytes sedimentation rate (ESR)?
- dextran
- methyldopa
- oral contraceptives
- penicillamine procainamide
- theophylline
- vitamin A
What can can decrease Erythrocytes sedimentation rate (ESR)?
- aspirin
- cortisone
- quinine
What is anemia?
Decrease of hemoglobin concentration below reference ranges for age and gender
What does anemia do?
It stimulates several compensatory mechanisms:
- tachypnoe
- tachycardia
- EPO
How is anemia classified?
- Classification based on pathophysiology
- Classification based on MCV
(SE TABLE page 4/11)
What are the markers of hemolysis?
- ↑ LDH
- ↑ Bilirubin (unconjugated)
- ↓ haptoglobin
- ↑ plasma hemoglobin
- Hemoglobin in urine
- Hemosiderin in urine
What are the symptoms of hemolytic anemia?
- Jaundince
- fatigue
- tachycardia
- pallor
- pigmented gallstones
- back pain
- dark urine
- splenomegaly
Intravascular hemolysis:
- Schistocytes
- ↑LDH
- ↓haptoglobin
- ↑ free hemoglobin, urine hemoglobin
- hemosideruria
Extravascular hemolysis:
- Microspherocytes
- ↑LDH
- N or ↓haptoglobin
- ↑indirect bilirubin
- ↑urine and fecal urobilinogen
Autoimmune hemolytic anemia:
- Antibody attaches to red blood cell
- Opsonins cause RBCs destruction in spleen
- Others activate complement Warm autoimmune hemolytic anemia IgG antibodies that bind RBC in 37°C
Opsonins (google def:)
it is any molecule that enhances phagocytosis by marking an antigen for an immune response or marking dead cells for recycling
Cold autoimmune hemolytic anemia
- IgM antibodies that bind RBC in 0-22°C
- Diagnosis: positive DAT
Post-transfusion autoimmune hemolytic anemia:
Transfusion of red blood cells bearing an antigen foreign for recipient
Hemolytic disease of newborns diagnosis:
blood group typing of mother, father and neonate, DAT, indirect AT during pregnancy, fetal RBC in maternal blood enumeration
Hereditary spherocytosis:
- genetic defects of spectrin, ankiryn, band 3 protein, protein 4.2 and/or others erythrocytes plasma membrane proteins.
- Deficiency of cytoskeleton proteins results in characteristic red blood cell’s shape
What are spherocytes?
they are small, globulous, hyperchromic cells
Hereditary spherocytosis diagnosis:
- high MCHC
- high RDW
- spherocytes in blood film
- EMA test
- osmotic fragility test
- (SDS-PAGE) of RBC plasma membrane proteins
Thalassemia:
Mutation that leads to reduced production of a structurally normal globin chains
Thalassemia diagnosis:
- ↑RBC
- ↓ Hgb
- ↓↓ MCV
- hemoglobin electrophoresis shows ↑HbA2 and HbF
- target cells
- basophilic stiplings
What is sickle cell anemia (hemoglobinopathies)?
Mutation that leads to production of structurally abnormal globin chains
sickle cell anemia (hemoglobinopathies) symptoms?
The lack of tissue oxygen can cause attacks of sudden, severe pain, called pain crises
For how long does the sickle cells last?
only 10 to 20 days
What is sickle cell anemia (hemoglobinopathies) resistant to?
Plasmodium falciparum
Sickle cell anemia (hemoglobinopathies) diagnosis:
- blood film
- electrophoresis of Hb
What is Microangiopathic hemolytic anemia?
Disorder that share the ability to create a microvascular environment capable of shreding cells
What does Microangiopathic hemolytic anemia cause?
- Inducing endothelial injury, thrombosis
- Disseminated intravascular coagulation (DIC)
- thrombotic thrombocytopenic purpura
- hemolytic uremic syndrome (HUS)
- pregnancyassociated syndrome of hemolysis
- elevated liver enzymes
- low PLT (HELLP)
Microangiopathic hemolytic anemia diagnosis:
- schistocytes
- anemia
Glucose-6-phosphate dehydrogenase deficiency
- Red cel enzyme defect
- G6PD produce glutathion that absorbs free radicals, protecting HbF against oxidation
- Under the influence of excess oxidants RBCs hemolyse (broad beans, nitrofuarantoin)
Glucose-6-phosphate dehydrogenase deficiency diagnosis:
- Heinz bodies
- bite cells
- low G6PD activity
PK =
Puryvate kinase deficiency
Puryvate kinase deficiency (PK):
- PK is an important enzyme in glycolytic pathway, its activation leads to ATP production
- Progressive RBCs dessication
Puryvate kinase deficiency (PK) diagnosis:
- echinocytes
- NADH conversation to NAD
Paroxysmal nocturnal hemoglobinuria
Mutation in PIG-A gene of hematopoietic stem cell, that cause decrease production of GPI (glycosylphosphatidylinositol)
What is GPI is an anchor for?
GPI is an anchor for CD16, CD55, CD59 on RBC that protect cell against complement lysis
Paroxysmal nocturnal hemoglobinuria diagnosis:
- Ham test
- Flow
- Cytometry
Test for hemolytic anemias DAT:
Antihuman globulin binds to Fc of IgG on RBC and agluttinate RBCs – positive in AIHA, HDN, Post transfusion hemolysis
Test for hemolytic anemias EMA (eosin-5’-maleimide) test
<81% of ctrl fluorescence typical for HS
Test for hemolytic anemia osmotic fragility
used to measure erythrocyte resistance to hemolysis while being exposed to varying levels of dilution of a saline solution
Increased osmotic fragility:
- Hereditary spherocytosis
- Autoimmune spherocytosis
- Poisoning, Severe burns
Decreased fragility:
- Thalassemias
- Iron deficiency anemia
- Sickle cell anemia
Iron deficiency anemia symptoms:
- fatigue
- pallor
- pica (a desire to ingest solids such a rock, dirt or ice)
- atrophic glossitis
- koilonychias
- esophagal webs
Iron deficiency anemia diagnosis:
- ↓RBC
- ↓MCV
- ↓MCHC
- ↑RDW
- Anulocytes, microcytes, hypochromic RBCs, scattered elliptocytes
- ↓ ferritin (<15 µg/L), ↑TIBC, ↑sTfR
TIBC =
Total Iron binding capacity
ACD =
Anemia of chronic disease
What does Anemia of chronic disease (ACD) lead to?
It leads to normocytic, normochromic anemia
What does the bone marrow biopsy of Anemia of chronic disease (ACD) show?
Bone marrow biopsy shows abundant iron stores in the face of decreased iron uptake by erythroid precursors
Anemia of chronic disease (ACD) def:
Sustained systemic inflammation alters iron utilization in the marrow, suppresses hematopoiesis, and blunts the response of EPO
What does vitamin B12 deficiency lead to?
- megaloblastic anemia
- May produce a degenerative neurologic syndrome
What is Pernicious anemia (Addison-Biermer anemia)?
Pernicious anemia (Addison-Biermer anemia) is a deficiency of gastric intrinsic factor
Pernicious anemia =
Addison-Biermer anemia
What does folate deficiency lead to?
megaloblastic anemia
Folate deficiency:
- Nuclear maturation of bone marrow precursors lags behind cytoplasmic maturation
- Impairment of DNA synthesis
Where is dietary folate absorbed, and for how long does the body store it?
Dietary folate is absorbed in duodenum and the body stores are for 4-5 months
Megaloblastic anemia diagnosis:
- MCV > 115 fL
- Oval macrocytosis
- ↓ folate or vitamin B12
- Hypersegmented neutrophils
- Large platelets
- Schililing test for vit B12 deficiency diagnosis (rarely used)
Sideroblastic anemia:
- Iron is incorporated within mitochondria into porphyrin – heme is made
- Abnormal sequestration leads to development of ringed sideroblasts
Sideroblastic anemia diagnosis:
Two population of RBC normochromic macrocytes and hypochromic microcytes, >15% of ringed sideroblasts in BM (at least 10 siderotic granules that surround one third of nucleus)
Acute blood loss anemia:
Result of surgery, trauma, gastrointestinal pathology
Acute blood loss anemia more:
- Hemodilution and ↓hematocrit
- Normocytic anemia with marked reticulocytosis
- Neutrophilia
Aplastic anemia def:
- Complete absence of hematopoiesis
- May be isolated to single cell line
- Normocytic anemia with reticulocytopenia
What causes aplastic anemia?
Due to thymoma, EPO therapy, infection of parvovirus B19
Blackfan-Diamond syndrome:
aplastic anemia
congenital pure red blood cells displasia (aplasia?)
Erythrocytosis
Persistent elevation in the RBC mass
Hgb in men and women
> 18.5 g/dL (men) and >16.5 g/dL (women)
Primarily Erythrocytosis:
myeloproliferative neoplasm
Secondary Erythrocytosis:
low PaO2 states, abnormal H variants, neoplasms that produce EPO
Polycythemia vera:
- Clonal neoplastic proliferation of erythroid precursors
- Normocytic erythrocytosis, neutrophilia, basophilia, thrombocytosis
Criteria for diagnosis of Polycythemia vera:
- A1+A2+ any other A criterion or
- A1+A2+ any two B criteria
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