Anemias Of Decreased RBC Production ( Hypoproliferative Anemias)

Question 1

What are the general features of hypoproliferative anemias?

Answer 1

Heterogenous
Low reticulocyte count
Can have extrinsic or intrinsic causes
Subclassified by morphology

Question 2

What are the characteristics of microcytic hypochromic anemia?

Answer 2

Normal DNA synthesis
Normal nuclear maturation
Decreased RBC hemoglobin production
Cytoplasmic maturation defect

Question 3

What are the causes of microcytic hypochromic anemia?

Answer 3

1-Disorders of metabolism: iron deficiency, chronic disease
2-Disorders of heme synthesis: sideroblastic anemia
3-Disorders of globin chain synthesis: thalassemias

Question 4

What are the main causes of iron deficiency anemia?

Answer 4

1-Dietary deficiency-MC in children(breast milk has poor iron)
2-Impaired absorption (sprue, celiac)
3-Increased requirements ( growing children, pregnancy)
4-Chronic blood loss- MC in adults
Iron deficiency in post menopausal women and adult men is due to chronic blood loss until proven otherwise

Question 5

What is the normal iron metabolism?

Answer 5

Iron is absorbed in the duodenum
Ferroportin transports iron to blood
In blood iron bind to transferrin
Iron is stored by binding to ferritin or hemosiderin

Question 6

What are the physical findings suggestive of iron deficiency ?

Answer 6

Koilonychia- spooning of fingernails
Alopecia
Atrophic glossitis
Atrophic gastritis
Pica- unusual food cravings

Question 7

What are the findings in the peripheral blood smear in iron deficiency?

Answer 7

Microcytic hypochromic cells
Anisocytosis
Poikilocytosis
Low reticulocyte count
Mild thrombocytosis

Question 8

How to diagnose iron deficiency ?

Answer 8

Decreased serum iron and saturation%
Increased TIBC
Decreased serum ferritin (storage iron)
High serum soluble transferrin receptor

Question 9

What are the characteristics of anemia of chronic disease?

Answer 9

Second only to iron deficiency in incidence

Immune driven cytokine response causing disturbance in iron homeostasis and inhibition of bone marrow

Question 10

What are the findings in peripheral blood smear of anemia of chronic disease ?

Answer 10

Microcytic hypochromic or normocytic normochromic anemia
Normal RDW
Low reticulocyte count
No characteristic morphologic features

Question 11

How to diagnose anemia of chronic disease?

Answer 11

Decreased serum iron and % saturation
Decreased TIBC
Increased bone marrow iron
Normal soluble serum transferrin receptor

Question 12

What are the characteristics of sideroblastic anemia?

Answer 12

Abnormal iron metabolism within the RBC itself
Iron swells and distorts the mitochondria
Ringed sideroblasts

Question 13

How to diagnose sideroblastic anemia?

Answer 13

Increased serum iron and % saturation
Decreased or normal TIBC
Increased marrow iron
Variable soluble serum transferrin receptor

Question 14

What are the 2 classifications of macrocytic anemia?

Answer 14

Megaloblastic marrow

Non megaloblastic marrow

Question 15

What are the causes of megaloblastic marrow in macrocytic anemia?

Answer 15

Folate deficiency
Vitamin B12 deficiency
Copper deficiency
Drug effect

Question 16

What are the causes of non megaloblastic marrow in macrocytic anemia?

Answer 16

Drug effect
Alcohol abuse
Hypothyroidism
Aplastic anemia

Question 17

What are the characteristics of megaloblastic anemia?

Answer 17

Most common causes are B12 or folate deficiency
Results in defective nuclear maturation
Abnormally large peripheral blood erythrocytes and bone marrow erythroblasts
Megaloblastic myeloid precursors
Nuclear:cytoplasmic dyssynchrony of cell maturation

Question 18

What are the findings in peripheral blood smear of megaloblastic anemia?

Answer 18

Rare teardrop cells
Hypersegmented neutrophils
Oval macrocytes

Question 19

What is the bone marrow morphology in megaloblastic anemia?

Answer 19

Hypercellular marrow
Ineffective hematopoiesis
Megaloblastic features

Question 20

What are the laboratory diagnostic findings in megaloblastic anemia?

Answer 20

Serum B12 is decreased and somewhat decreased in folate deficiency
Serum folate fluctuates with diet so it is more accurate after 12 hours of fasting- normal or increased in B12 deficiency, decreased in folate and mixed deficiency
Methyl malonic acid is normal in folate and elevated in B12 and mixed deficiency
RBC folate is decreased in all

Question 21

What are the clinical features of aplastic anemia?

Answer 21

May occur at any age, either sex
Insidious onset
Pancytopenia usually develops
Can be acquired ( more common) idiopathic or inherited (Fanconi anemia,telomerase defects)

Question 22

What are the characteristics of Fanconi anemia?

Answer 22

Autosomal recessive congenital 
Defect of DNA repair
Has bone, skin and renal abnormalities 
Mental retardation 
Usually die  of marrow failure
If live long enough, at risk of leukemia

Question 23

What are the characteristics of pure red cell aplasia?

Answer 23

Primary marrow disorder in which only erythroid progenitors are suppressed
Causes can be neoplasms (thymoma),drug exposures,autoimmune diseases, parvovirus B19 infection

Question 24

What are the characteristics of inherited red cell aplasia: Blackfan-Diamond syndrome?

Answer 24

Bone marrow grossly reduced or absent erythroid precursors
Granulopoiesis is unaffected
No giant erythroblasts
Defect in generation of ribosomes in RBC precursors