Anemia Lecture

Question 1

Acute anemia increase in RBC production

Answer 1

3x within 7-10 days

Question 2

Chronic anemia increase in RBC production

Answer 2

6x - 8x

Question 3

Average adult blood volume

Answer 3

5 L total = 3 L plasma + 2 L blood cells

Question 4

Hb

Answer 4

Hemoglobin concentration (g/L)

Question 5

Hematocrit

Answer 5

Packed red cell volume (%)

Question 6

MCV

Answer 6

• Mean corpuscular volume

- Average size of a RBC

Question 7

MCH

Answer 7

• Mean corpuscular hemoglobin
• Average amount/mass of Hb in a RBC
• = Hb/RBC count

Question 8

RDW

Answer 8

• Red cell distribution width

- Coefficient of variation of RBC volume, variation in cell size

Question 9

MCHC

Answer 9

• Mean corpuscular hemoglobin concentration

- Proportion of each red cell taken up by Hb (%)

Question 10

Microcytic anemia

Answer 10

Decreased MCV, MCH, MCHC

Question 11

Normocytic anemia

Answer 11

Normal MCV, MCH, MCHC

Question 12

Macrocytic anemia

Answer 12

• Increased MCV

- Variable MCH and MCHC

Question 13

Transferrin saturation

Answer 13

TRF = Concentration Fe / TIBC

Question 14

Megaloblastic anemia and folate

Answer 14

Folate treatment partially corrects B12 deficiency but does NOT affect neurologic defecits

Question 15

Production deficit anemias include

Answer 15

• Aplastic anemia

- Pure red cell aplasia → Diamond - Blackfan syndrome

Question 16

Aplastic anemia

Answer 16

Acquired causes:

• Viral infections: hepatitis, EBV, HIV, parvovirus
• MOST COMMON CAUSES: autoimmune suppression by a T cell mediated mechanism

Hereditary causes - FANCONI’S ANEMIA:

• AR
• Defects in DNA REPAIR MECHANISM = chromosomal instability
• Congenital anomalies (hypoplastic radii, thumbs and organs)
• May be pre-malignant: evolves into myelodysplasia, AML, CML

Question 17

Pure red cell aplasia

Answer 17

• Autoimmune disease mediated by T lymphocytes of IgG antibody VS red cell precursors
• Associated with: SLE, CLL, lymphomas, THYMOMAS
• Diamond-Blackfan syndrome
• Drugs: phenytoin, azathioprine, isoniazid

Question 18

Sideroblastic anemia - nutritional deficiency

Answer 18

Pyridoxine (B6) and copper

Question 19

Hemolytic anemia

Answer 19

ACUTE SYMPTOMS: fatigue, fever, pallor, jaundice, LOW BACK PAIN, splenomegaly, CONGESTIVE HEART FAILURE

CHRONIC SYMPTOMS: acute + gallstones, abnormal bone growth, fractures

LAB FINDINGS:

• ↑ unconjugated bilirubin
• ↓ serum haptoglobin concentration (which take up free Hb)
• ↑ serum LDH (RBC enzyme release
• Reticulocytosis

INTRAVASCULAR HEMOLYSIS:
- Free hemoglobin released → haptoglobin released: excessive free Hb = hemoglobinuria and hemoglobinsiderinuria; EXPECT ↓ SERUM HAPTOGLOBIN CONCENTRATION

Question 20

Beta thalassemia VS Iron deficiency anemia

Answer 20

• Iron therapy improves iron deficiency anemia, worsens beta thalassemia
• Increased or normal serum iron and bone marrow iron in thalassemia

Question 21

Hereditary spherocytosis treatment

Answer 21

Treat with FOLIC acid supplements or SPLENECTOMY

Question 22

G6PD deficiency smears between attacks

Answer 22

Between attacks peripheral smears are normal

Question 23

WAHA and disease

Answer 23

WAHA may antedate the onset of disease by months or years

Question 24

CAD causes

Answer 24

ACUTE: associated with atypical pneumonia (against big I) and infectious mononucleosis (against little i)

CHRONIC: due to lymphoid malignancy or idiopathic, may be unremitting

Question 25

Paroxysmal cold hemoglobinuria

Answer 25

- IgG autoantibody (Donath-Landsteiner Ab) = biphasic hemolysis - AT LOW TEMPS binds to cells without causing hemolysis - WARMING binds complement → intravascular hemolysis, hemoglobinuria - No jaundice or splenomegaly Test for Donath-Landsteiner Ab → differentiates PCH from CAD - Mix patients serum (with antibody) with test RBCs - First chill them then warm them to 38C - Lysis of RBCs indicates PCH

Question 26

Test for hemolytic transfusion reaction

Answer 26

Coombs test

Question 27

Microangiopathic hemolytic anemias

Answer 27

Due to abrnomalities in microcirculation → fibrin deposition and vessel narrowing - DIC - HUS - Thrombotic-thrombocytopenia purpura (TTP) - Preeclampsia, HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets)

Question 28

Paroxysal nocturnal hemoglobinuria

Answer 28

- CD59 (MIRL, membrane inhibitor of reactive lysis) and CD55 (DAF) need GPI membrane - Can evolve into: aplastic anemia, myelodysplasia, AML - TREATMENT: iron supplement, prednisone, BM transplant

Question 29

Mechanical and physical factors that cause nonimmune hemolytic anemia

Answer 29

- Prosthetic heart valces - BURN INJURY: microspherocytes, barbell shapes, rod shapes - MARCH HEMOGLOBINURIA: marching, marathon running, drum beating; hemoglobinuria after exercise; normal peripheral blood smear; anemia is rare in these individuals