Anemias DDx

Question 1

What are some causes of intravascular hemolysis that would not cause an abnormal MCV?

Answer 1

• Cold Autoimmune Hemolytic Anemia
• G6PD deficiency
• Paroxysmal Nocturnal Hemoglobinuria
• Thrombotic Thromobocytopenia Purpura (TTP)
• HUS and aHUS (hemolytic uremic syndrome)

**Normal MCV means normocytic Anemia

Question 2

What are some different features on a peripheral blood smear that help to differentiate what kind of intravascular hemolysing, normocytic anemia you are dealing with?

Answer 2

Note as with all normocytic anemias (that dont involve malignancy) we should see reticulocytes forming

Cold Autoimmune Hemolytic Anemia
• Agglutination on the smear that resolves when the slide is heated up

G6P deficiency
• Blister Cells from inclusions of oxidized Hgb
• Basophilic Stippling WITH METHYLENE blue stain

TTP, HUS, or aHUS
• Schistocytes

Paroxysmal Hemoglobinurea
• Should look normal unless person is loosing so much blood so as to become iron deficient
• If iron deficient look for Hypochromia, Anisocytosis, Poikilocytosis

Question 3

What are 3 general reasons you would have a normocytic anemia?
• what is the 1 overarching reason?

Answer 3

Normocytic - Hemolysis is Happening

• Infection with hemolytic microbe
• Intravascular Hemolysis
• Extravascular Hemolysis