Erythropoiesis Flashcards
Define erythropoiesis.
Production of RBCs in the bone marrow
What hormone controls erythropoiesis?
EPO- erythropoietin
Where is EPO synthesized?
Renal cortex
List the stimuli for EPO release.
Hypoxemia Decreased oxygen saturation Severe anemia L-shift oxygen binding curve High altitude
What inhibits EPO release?
Increased oxygen content
What drug is commonly used by athletes to enhance performance. This drug is also used to treat anemia associated with renal failure, chronic disease, and chemotherapy.
Epoetin alfa
What are ectopic sources of EPO?
Renal cell carcinoma
Hepatocellular carcinoma
What is a reticulocyte?
Newley released RBC from the bone marrow
What does the reticulocyte count measure?
Effectiveness of erythropoiesis
What is effective erythropoiesis?
Good bone marrow response to anemia, i.e. increased synthesis/release of of reticulocytes
What is a normal reticulocyte count?
Using the percentage reticulocyte count in anemia gives a falsely increased percentage, thus, you must correct the reticulocyte count for the degree of anemia. Give the formula for the corrected reticulocyte count.
Corrected reticulocyte count = (Pts Hct/45)*reticulocyte count
In what situation do you need to make an additional correction to the reticulocyte count?
If polychromasia is present- divide corrected reticulocyte count by 2
In the setting of anemia, what does a corrected reticulocyte greater than, and less than 3% indicate?
Greater than 3%: effective erythropoiesis
Less than 3%: ineffective erythropoiesis
Define extramedullary hematopoiesis.
RBC, WBC, and platelet production that occurs outside the bone marrow
