CLASSIFICATION OF ANEMIA

Question 1

• MCV: > 96fL
• MCHC: Normal

Answer 1

MACROCYTIC NORMOCHROMIC ANEMIA (MNA)

Question 2

• Abnormal erythroblast in BM.
• Delayed maturation of blood cell.

Answer 2

Megaloblastic MNA

Question 3

Macrocytosis but BM RBCs are normoblastic.

Answer 3

Non-megaloblastic MNA

Question 4

Causes of Megaloblastic MNA

Answer 4

✓ Vit. B12 def: pernicious anemia
✓ Folic acid def: nutritional megaloblastic anemia
✓ Abnormalities of Vit. B12 or folate metabolism
✓ Inherited disorders of DNA synthesis
✓ Drug-induced disorders of DNA synthesis

Question 5

Megaloblastic MNA lab findings

Answer 5

✓ Macrocytic RBCs: MCV >95fl & often as high as 120-140fl.
✓ Macrocytes are typically oval shape.
✓ ↓Retic ct. in relation to the degree of anemia.
✓ Moderately ↓total white cell ct. & plt cts esp. in severely anemic px.

Question 6

Megaloblastic MNA in Peripheral smears

Answer 6

✓ Normal RBC morphology despite drop of Hgb, Hct, & RBC ct.
✓ ↑BM activity (↑retic ct.) w/out ↑RBC hr hgb breakdown)

Question 7

Causes of non-megaloblastic mna

Answer 7

✓ Accelerated erythropoiesis
✓ ↑membrane surface area
✓ Obscure causes (hypoplastic & aplastic anemias)
✓ Alcohol
✓ Liver dsz
✓ Cytotoxic drugs (Ex. metronidazole for amoebiasis)
 Metronidazole is a cancer-causing agent.

Question 8

• Small RBC, ↓hgb, <80fl MCV, <32% MCHC

Answer 8

MICROCYTIC HYPOCHROMIC ANEMIA (MHA)

Question 9

Causes of MHA

Answer 9

✓ Iron def
✓ Globin synthesis disorder as in thalassemia
✓ Porphyrin & heme synthesis disorder as in sideroblastic anemia
✓ Other disorders of iron metabolism

Question 10

MHA in PBS shows

Answer 10

✓ Aniso- & Poikilocytosis
✓ Microcytic RBCs since many are smaller than nucleus of the lymphocyte.
✓ Hypochromic RBCs w/ ↑central pallor.
✓ Elliptocytic & pencil-shaped forms are present.

Question 11

• w/ effective erythropoiesis: ↑retic ct
  o Acute blood loss
  ✓ Very acutely, w/ hypovolemia, may have normal blood cts, will become anemic w/ volume replenishment.
  o Hemolytic anemia
  ✓ ↑retic ct. production cannot keep pace w/ loss of RBCs peripherally.
  o Response to specific therapy in nutritional anemias.

Answer 11

NORMOCYTIC NORMOCHROMIC ANEMIA (NNA)

Question 12

Causes of NNA

Answer 12

✓ Recent blood loss
✓ Overexpansion of plasma volume as in pregnancy
✓ Hemolytic dsz
✓ Hypoplastic BM (aplastic anemia)
✓ Infiltrated BM (leukemia)
✓ Endocrine abnormality
✓ Chronic disorders
✓ Renal disorders
✓ Liver dsz