Anemia 1 Flashcards
Define hematocrit.
- ratio of the volume of RBCs to that of whole blood
- 3x[Hb] approximately
4 components of peripheral blood.
-RBC, WBC, platelets, plasma
MCV vs. RDW
- MCV: mean cell volume; average volume of red cell in specimen
- RDW: red cell distribution; measure of the variation of the RBC volume in specimen
Parameters of microcytic, normocytic, and macrocytic.
-micro: MCV100
What does it mean if a RBC is hypochromic?
-increased central pallor so that it is greater than 1/3 of the RBC diameter
T/F: A reticulocyte has a nucleus while an erythrocyte does not.
-False, neither have nuclei. The reticulocyte is slightly larger and blue-er because it still contains rRNA
Define anemia and give its overall result.
- decrease in the # of RBCs or less than the normal quantity of Hb in the blood
- overall reduction in O2 carrying capacity of the blood, leading to tissue hypoxia
3 general mechanistic categories of anemia.
- decreased production
- increased destruction
- loss due to bleeding
What does a high or low reticulocyte count suggest about an anemia patient?
- high: destructive problem or bleeding problem; marrow is appropriately trying to compensate for reduction in O2-carrying capacity by making more RBC
- low/normal: suggests production problem; marrow is not responding appropriately to the low O2-carrying capacity, so suggests it is the cause of problem
An anemic patient’s MCV came back to be <80, what is on your differential diagnosis? Do the same for normocytic and macrocytic anemias.
Micro: iron deficiency anemia, thalassemia, anemia of chronic disease, sideroblastic anemia
Normo: hemolytic anemia, hemorrhage/blood loss, sickle cell disease, anemia of chronic disease, aplastic anemia
Macro: megaloblastic anemia ( due to meds, B12/folate deficiency), liver disease, alcohol, toxins, myelodysplastic syndrome
Who is at risk for iron deficiency anemia? What will their blood smear look like? What is the follow up for these patients?
- toddlers, adolescent girls, women of childbearing age, older adults with occult blood loss
- microcytic, hypochromic anemia, high RDW; can see pencil cells occasionally
- iron studies and bone marrow (usually not needed but will show decreased iron stores)
How will thalassemia appear on a blood smear? How can you tell this apart from other smears with potentially the same characteristics?
- microcytic, hypochromic anemia like iron deficiency anemia BUT often has VERY low (<70) MCV and not as high of a RDW
- target cells seen
What type of anemia can Hereditary Spherocytosis cause? What does its peripheral smear look like?
- hemolytic anemia due to tendency for hemolysis in spleen
- normochromic, normocytic anemia with high retic count and spherocytes are present
What does a spherocyte look like?
- RBC that has lost membrane and taken on spherical shape
- lack of central pallor
Describe the surface area: volume ratios of normal RBCs, spherocytes, and target cells.
- Normal is baseline
- Spherocytes is low SA:V
- Target cell is high SA:V
Megaloblastic anemia is on the differential for what RBC size? Give 3 things that can cause it.
- macrocytic: most common type of macrocytic anemia
- B12 deficiency, folate deficiency, medications
Give 2 characteristics seen on peripheral blood smear from someone with megaloblastic anemia.
- macrocytic RBCs
- hypersegmented neutrophils
Common causes of global anemias
- iron deficiency
- other nutritional deficits like Vit A, B, folic acid
- infectious disease: malaria, hookworm, HIV/AIDS, TB
- congenital causes: hemoglobinopathies
4 consequences of anemia
- increased risk of maternal and child mortality
- adverse effects on cognitive and physical development of children
- decreased work productivity
- increased postoperative morbidity
3 things mature RBCs lack.
-nucleus, mitochondria (only glycolysis), ribosomes (no longer makes Hb)
How many hemes does a molecule of Hb contain?
-4; one on each a2B2 subunit
If one were to classify an anemia off of mechanistic approach vs. a morphologic approach, what would they analyze for either approach?
- mechanistic: retic count
- morphologic: MCV
Reticulocyte count vs. corrected reticulocyte count.
- RC: % of circulating RBCs which appear to be reticulocytes
- CRC: in anemia, the total RBC is low and therefore, we need to be a correction to judge the actual number of retics being made by BM; = % retics x (actual HCT)/(ideal HCT)
4 categories of decreased RBC production
- lack of building blocks: Fe, folate, B12 deficiency
- inability to use iron: anemia of chronic disease
- EPO deficiency: renal disease
- Lack of RBC precursors: aplastic anemia, toxins, immune-mediated
