NR 507 Final Exam Study Guide – Normocytic
Anemias & Hemoglobinopathies
Basic Principles of Normocytic Anemia - ANS -Anemia with normal RBC size (MCV = 80 -100 fL)
Due to increased peripheral destruction or underproduction -- count reticulocytes to distinguish
What are Reticulocytes? What do they look like on a blood smear? What is a normal
Reticulocyte count? - ANS -Young RBCs released from Bone Marrow. Identified on blood smear
as larger cells with bluish cytoplasm. Normal reticulocyte count is 1 -2 %
Why are Reticulocytes falsely elevated in anemia? - ANS -Properly functioning marrow responds
to anemia by increasing the RC to > 3%. But because RC count is percent it seems falsely
elevated.
How to we correct the false Reticulocyte count? - ANS -Multiply RC count by Hct/45
Corrected count > 3% - ANS -marrow is doing its job properly so anemia must be due to
peripheral destruction, not marrow underproduction
Corrected count < 3% - ANS -marrow is underproducing
What is the difference between extravascular peripheral destruction and intravascular
hemolysis? - ANS -Both result in anemia with good marrow response. Extravascular Hemolysis =
RBC destruction by reticuloendothelial system (macrophages of spleen, liver and lymph nodes)
Intravascular Hemolysis = RBC destroyed in vessels
, Clinical and Lab findings of extravascular hemolysis? - ANS -1. Anemia with splenomegaly,
jaundice due to unconjugated bilirubin (bc increased destruction of RBC) and increased risk for
gall stones (bc increased saturation of bile).
2. Marrow hyperplasia with corrected reticulocyte count > 3%
Clinical and Lab findings of intravascular hemolysis? - ANS -Hemoglobinemia
Hemoglobinuria
Hemosiderinuria
Decreased Serum Haptoglobin
Why is Hemosiderinuria observed in Intravascular hemolysis? - ANS -Renal tubular cells pick up
some of the hemoglobin that is filtered into the urine and break it down into iron , which
accumulates as hemosiderin. Tubular cells are eventually shed resulting in hemosiderinuria.
Why is there decreased serum Haptoglobin in intravascular hemolysis? - ANS -Haptoglobin is
responsible for binding Hb in the blood when it is released from RBC. Haptoglobin transfers Hb
to spleen. If RBCs are getting destroyed, more Hb is being released into the blood and
Haptoglobins bind therefore there is less free haptoglobin.
List the predominantly extravascular hemolytic anemias - ANS -Hereditary Spherocytosis
Sickle Cell Anemia
Hemoglobin C (?)
List the predominantly intravascular hemolytic anemias - ANS -Paroxysmal Nocturnal
Hemoglobinuria (PNH)
Glucose 6 Phosphate Dehydrogenase Deficiency
Immune Hemolytic Anemia
Microangiopathic Hemolytic Anemia
Anemias & Hemoglobinopathies
Basic Principles of Normocytic Anemia - ANS -Anemia with normal RBC size (MCV = 80 -100 fL)
Due to increased peripheral destruction or underproduction -- count reticulocytes to distinguish
What are Reticulocytes? What do they look like on a blood smear? What is a normal
Reticulocyte count? - ANS -Young RBCs released from Bone Marrow. Identified on blood smear
as larger cells with bluish cytoplasm. Normal reticulocyte count is 1 -2 %
Why are Reticulocytes falsely elevated in anemia? - ANS -Properly functioning marrow responds
to anemia by increasing the RC to > 3%. But because RC count is percent it seems falsely
elevated.
How to we correct the false Reticulocyte count? - ANS -Multiply RC count by Hct/45
Corrected count > 3% - ANS -marrow is doing its job properly so anemia must be due to
peripheral destruction, not marrow underproduction
Corrected count < 3% - ANS -marrow is underproducing
What is the difference between extravascular peripheral destruction and intravascular
hemolysis? - ANS -Both result in anemia with good marrow response. Extravascular Hemolysis =
RBC destruction by reticuloendothelial system (macrophages of spleen, liver and lymph nodes)
Intravascular Hemolysis = RBC destroyed in vessels
, Clinical and Lab findings of extravascular hemolysis? - ANS -1. Anemia with splenomegaly,
jaundice due to unconjugated bilirubin (bc increased destruction of RBC) and increased risk for
gall stones (bc increased saturation of bile).
2. Marrow hyperplasia with corrected reticulocyte count > 3%
Clinical and Lab findings of intravascular hemolysis? - ANS -Hemoglobinemia
Hemoglobinuria
Hemosiderinuria
Decreased Serum Haptoglobin
Why is Hemosiderinuria observed in Intravascular hemolysis? - ANS -Renal tubular cells pick up
some of the hemoglobin that is filtered into the urine and break it down into iron , which
accumulates as hemosiderin. Tubular cells are eventually shed resulting in hemosiderinuria.
Why is there decreased serum Haptoglobin in intravascular hemolysis? - ANS -Haptoglobin is
responsible for binding Hb in the blood when it is released from RBC. Haptoglobin transfers Hb
to spleen. If RBCs are getting destroyed, more Hb is being released into the blood and
Haptoglobins bind therefore there is less free haptoglobin.
List the predominantly extravascular hemolytic anemias - ANS -Hereditary Spherocytosis
Sickle Cell Anemia
Hemoglobin C (?)
List the predominantly intravascular hemolytic anemias - ANS -Paroxysmal Nocturnal
Hemoglobinuria (PNH)
Glucose 6 Phosphate Dehydrogenase Deficiency
Immune Hemolytic Anemia
Microangiopathic Hemolytic Anemia
