Fa: Hem / Onc - Pathology (Rbc & Platelets) - 1B

Front 1

How can you categorize the types of anemias?

Back 1

- Microcytic (MCV <80 fL)
- Normocytic (MCV 80-100 fL)
- Macrocytic (MCV >80 fL)

Front 2

What are the types of microcytic anemias? Definition?

Back 2

MCV <80 fL
- Iron deficiency (late)
- Anemia of chronic disease (may initially present as a normocytic anemia)
- Thalassemias
- Lead poisoning
- Sideroblastic anemia

Front 3

What are the types of normocytic anemias? Definition?

Back 3

MCV 80-100 fL

Non-hemolytic (reticulocyte count normal or ↓)

Hemolytic (reticulocyte count ↑)
- Intrinsic
- Extrinsic

Front 4

What are the types of non-hemolytic, normocytic anemias? Definition?

Back 4

MCV 80-100 fL and reticulocyte count normal or ↓
- Anemia of chronic disease (may progress to microcytic anemia)
- Aplastic anemia
- Chronic kidney disease
- Iron deficiency (early, may progress to microcytic)

Front 5

What are the types of intrinsic hemolytic, normocytic anemias? Definition?

Back 5

MCV 80-100 fL with increased reticulocyte count
- RBC membrane defect (hereditary spherocytosis)
- RBC enzyme deficiency (G6PD or pyruvate kinase)
- HbC defect
- Paroxysmal nocturnal hemoglobinuria
- Sickle cell anemia

Front 6

What are the types of extrinsic hemolytic, normocytic anemias? Definition?

Back 6

MCV 80-100 fL with increased reticulocyte count
- Auto-immune
- Microangiopathic
- Macroangiopathic
- Infections

Front 7

What are the types of macrocytic anemias? Definition?

Back 7

MCV >100 fL

- Megaloblastic
- Non-megaloblastic

Front 8

What are the types of macrocytic, megaloblastic anemias? Definition?

Back 8

MCV >100 fL
- Folate deficiency
- B12 deficiency
- Orotic aciduria

Front 9

What are the types of macrocytic, non-megaloblastic anemias? Definition?

Back 9

MCV >100 fL
- Liver disease
- Alcoholism
- Reticulocytosis

Front 10

What is the most likely cause of this patient's conjunctival pallor?

Back 10

Anemia (possibly due to iron deficiency)

Front 11

What causes iron deficiency anemia?

Back 11

Decreased iron due to:
- Chronic bleeding (eg, GI loss or menorrhagia)
- Malnutrition / absorption disorder
- ↑ Demand (eg, pregnancy)

Front 12

What are the implications of an iron deficiency?

Back 12

Decreased completion of final step in heme synthesis

Front 13

What lab findings are associated with iron deficiency anemia?

Back 13

- MCV < 80 fL (microcytic)
- ↓ Iron
- ↑ TIBC
- ↓ Ferritin
- Hypochromia

Front 14

What other unrelated symptoms should you look for in a patient with iron deficiency anemia to check for another syndrome?

Back 14

Plummer-Vinson Syndrome:
- Also esophageal webs and atrophic glossitis

Front 15

What is the term for the triad of iron deficiency anemia, esophageal webs, and atrophic glossitis?

Back 15

Plummer-Vinson Syndrome

Front 16

What are the symptoms in Plummer-Vinson Syndrome?

Back 16

- Iron deficiency anemia
- Esophageal webs
- Atrophic glossitis

Front 17

What does this blood smear tell you?

Back 17

Iron Deficiency Anemia
- Microcytosis
- Hypochromia (central pallor)

Front 18

What is the defect in α-thalassemia?

Back 18

α-globin gene deletions → ↓ α-globin synthesis

Front 19

What kind of deletions can lead to α-thalassemia?

Back 19

- Cis deletion prevalent in Asian populations
- Trans deletion prevalent in African populations

Front 20

How many copies of the α-globin gene do you have? Implications?

Back 20

4 alleles:
- 1-2 allele deletion → no significant anemia
- 3 allele deletion → HbH disease, very little α-globin, excess β-globin forms β4 (HbH)
- 4 allele deletion → no α-globin, excess γ-globin forms γ4 (Hb Barts); incompatible with life (causes hydrops fetalis)

Front 21

What causes hydrops fetalis?

Back 21

4 α-globin allele deletion:
- No α-globin
- Excess γ-globin forms γ4 (Hb Barts)
- Incompatible with life

Front 22

What causes HbH disease?

Back 22

3 α-globin allele deletion:
- HbH disease, very little α-globin
- Excess β-globin forms β4 (HbH)

Front 23

What form of α-thalassemia is more common in Asians?

Back 23

Cis deletion of α-globin alleles

Front 24

What form of α-thalassemia is more common in Africans?

Back 24

Trans deletion of α-globin alleles

Front 25

Who is more likely to have β-thalassemia?

Back 25

Prevalent in Mediterranean poulations

Front 26

What causes β-thalassemia?

Back 26

Point mutations in splice sites and promoter sequences → ↓ β-globin synthesis

Front 27

What are the types of β-thalassemia?

Back 27

- β-thalassemia minor (heterozygote)
- β-thalassemia major (homozygote)
- HbS / β-thalassemia heterozygote

Front 28

What is the most severe form of β-thalassemia?

Back 28

β-thalassemia major (homozygote)
- β chain is absent → severe anemia

Front 29

What are the consequences of having absent β chain (β-thalassemia major)?

Back 29

- Severe anemia → requires blood transfusion
- Marrow expansion → skeletal deformities → "crew cut" on skull x-ray
- Chipmunk facies
- Extramedullary hematopoiesis → hepatosplenomegaly
- ↑ Risk of parvovirus B19-induced aplastic crisis

Front 30

What kind of infection are patients with β-thalassemia major at risk for? Complications?

Back 30

Parvovirus B19 → can induce an aplastic crisis

Front 31

What kind of hemoglobin is more common in patients with β-thalassemia major?

Back 31

HbF (α2γ2) - protective in the infant and disease only becomes symptomatic after 6 months

Front 32

What is the medium severity form of β-thalassemia?

Back 32

HbS / β-thalassemia heterozygote
- Mild to moderate sickle cell disease depending on the amount of β-globin production

Front 33

What is the least severe form of β-thalassemia?

Back 33

β-thalassemia Minor (heterozygote)
- β chain is underproduced, usually asymptomatic

Front 34

How do yo confirm diagnosis of β-thalassemia minor (heterozygote)?

Back 34

Confirm diagnosis by ↑ HbA2 (>3.5% on electrophoresis)

Front 35

What happens to RBCs in patients with β-thalassemia major?

Back 35

Note anisocytosis, poikilocytosis, target cells (arrows 1 and 2), microcytosis (arrow 3), and schistocytes (arrow 4)

Front 36

How does lead poisoning affect the blood?

Back 36

- Lead inhibits ferrochelatase and ALA dehydratase → ↓ heme synthesis and ↑ RBC protoporphyrin
- Also inhibits rRNA degradation, causing RBCs to retain aggregates of rRNA (basophilic stippling)

Front 37

Who is at risk for lead poisoning?

Back 37

High risk in old houses with chipped paint

Front 38

How does lead poisoning affect other organs besides the blood?

Back 38

LEAD:
- Lead Lines on gingivae and on metaphyses of long bones on x-ray
- Encephalopathy and Erythrocyte basophilic stippling
- Abdominal colic and sideroblastic anemia
- Drops: wrist and foot drop

Front 39

What does the arrow point at? Sign of?

Back 39

- Lead Lines on metaphyses of long bones on x-ray
- Sign of Lead Poisoning

Front 40

How does lead affect the gums?

Back 40

Lead Lines on gingivae = Burton lines
- Sign of lead poisoning

Front 41

How does lead affect the brain?

Back 41

Can cause encephalopathy

Front 42

How does lead affect the musculoskeletal system?

Back 42

Drops: wrist and foot drops

Front 43

How does lead affect the abdomen?

Back 43

Abdominal colic

Front 44

How do you treat lead poisoning?

Back 44

First line treatments:
- Dimercaprol
- EDTA

Succimer used for chelation for kids ("it sucks to be a kid who eats lead")

Front 45

What is wrong in this picture? Cause?

Back 45

Sideroblastic Anemia
- Defect in heme synthesis
- Hereditary: X-linked defect in δ-ALA synthase gene

Front 46

What causes sideroblastic anemia?

Back 46

- Genetic
- Acquired (myelodysplastic syndromes)
- Reversible (alcohol is most common, lead, vitamin B6 deficiency, copper deficiency, and isoniazid)

Front 47

What causes acquired sideroblastic anemia?

Back 47

Myelodysplastic syndromes

Front 48

What causes reversible sideroblastic anemia?

Back 48

- Alcohol is most common
- Lead
- Vitamin B6 deficiency
- Copper deficiency
- Isoniazid

Front 49

What are the lab findings in sideroblastic anemia?

Back 49

- ↑ Iron
- Normal TIBC
- ↑ Ferritin

Front 50

How do you treat Sideroblastic Anemia?

Back 50

Pyridoxine (B6, cofactor for δ-ALA synthase)