Anemia - Johns Flashcards
Define Anemia
Reduction in one or more of the following RBC concentration measurements:
Hemoglobin
Hematocrit
RBC Count
What is the key test for anemia?
Reticulocyte Count (adjusted for hematocrit)
What are two causes of anemia?
Low RBC Production
Too Much RBC Destruction
What are reticulocytes?
Early precursors of mature blood cells
What is an increase reticulocyte count and when is it seen?
100,000 or more than 2-3% seen in blood loss and hemolytic processes
If the reticulocyte count is normal, this signals an issue with RBC…
Production
If the reticulocyte count is high, this signals an issue with RBC…
Increased Destruction
How do you determine RBC size?
MCV = Mean Corpuscular Volume
What is the MCV for Macrocytic Anemia?
MCV > 100
What are the two main causes for Macrocytic Anemia?
Vitamin B12 and Folic Acid Deficiencies
What causes a Vitamin B12 Deficiency?
Decreased gastric secretion of intrinsic factor (rarely diet)
What causes a Folic Acid Deficiency?
Poor diet, alcohol, malabsorption, increased demand due to pregnancy or hemolytic anemias
What are Vitamin B12 and Folic Acid used for in the body?
DNA synthesis of deoxyuridate to thymidylate
Treatment for Vitamin B12 Deficiency
B12 1mg/month IM or 1-2 mg/day po
Treatment for Folate Deficiency
Diet, Folate 1 mg/day
What is a secondary cause of Macrocytic Anemia?
Drugs that impair DNA synthesis such as AZT, Chemo, alcohol
What is the MCV for Microcytic Anemia?
MCV
What are the causes of Microcytic Anemia?
Iron Deficiency
Thalassemia
Anemia of Chronic Disease
Sideroblastic Anemia
What labs should be seen for Iron Deficiency Anemia?
Decreased Hemoglobin Decreased Serum Iron Decreased Iron Saturation (Fe/TIBC) Decreased Ferritin Normal/Increased TIBC - total iron binding capacity
Thalassemias
Genetic defect found in Africans, Asians, and Mediterraneans in hemoglobin synthesis leads to ineffective erythropoiesis
What is the MCV for Normocytic Anemia?
MCV = 80-100
What are the causes for normocytic anemia?
Anemia of Chronic Disease (SLE, RA)
Mixed deficiencies
Renal Failure
What labs should be seen for Anemias of Chronic Disease?
Decreased serum iron
Decreased serum TIBC
Normal/Increased Ferritin
Normal Fe/TIBC
Define Sideroblastic Anemias
Heterogenous grouping with presence of ringed sideroblasts in the bone marrow
