CBC Flashcards
How long does it take for RBCs to from from stem cells?
7 days
How long do RBCs live?
~120 days
How long does it take for reticulocytes to mature in circulation?
1 day
What is a normal retic count? Why?
RBC production should equal destruction.
So, RBCs are destroyed at a rate of 0.8%-1%
Normal reticulocyte count 1-2%
IF you have a high amount of reticulocytes, what will the CBC look like?
INCREASED MCV
INCREASED RDW
Normal WBC
5,000-10,000/mm3
Normal Hemoglobin
Men: 14-18 g/dL
Women: 12-16 g/dL
Hematocrit
percentage of whole blood made up of RBCs
Mean Cell Volume (MCV)
>100 = macrocytosis 80-100 = normocytic <80 = microcytosis
(fL - fenoliters)
Mean Cell Hemoglobin (MCH)
weight of the hemoglobin in the RBC
Mean Cell Hemoglobin Concentration (MCHC)
Normal: ~31-35%
Red Cell Distribution Width (RDW)
Range in cell size
Normal: 12-15%
Anisocytosis
- abnormalities of size
- correlates with RDW
Poikilocytosis
- abnormalities in shape
- suggests defect in the precursor cells
Hyperchromasia
Causes:
- dehydration
- spherocytes
Polychromasia
-blue staining RBCs
Peripheral smear: target cells
Suggests:
- Hemoglobinopathy
- Thalassemia
- Liver disease
Peripheral smear: Basophilic stippling
- represent ribosomal precipitates
1. Thalassemia
2. Alcohol abuse
3. Lead/heavy metal poisoning
Peripheral smear: Rouleaux formation
Associated with Multiple myeloma
Peripheral smear: Fragmented cells
- Schistocytes
- Helmet cells
Associated with:
- Mechanical heart valve
- DIC
- Thrombotic thrombocytopenic purpura (TTP)
Heinz bodies
Aggregates of denatured hemoglobin
Seen in:
- G6PD deficiency**
- Autoimmune hemolytic anemia
- Thalassemia
Bite cells
Removal of hemoglobin precipitate by macrophages
Seen in”
- G6PD deficiency**
- hemolytic anemia
Howell-Jolly Bodies
Small, round remnants of DNA
Seen in:
- Sickle cell
- Splenectomy
- Hemolytic anemia
- Megaloblastic anemia
Smudge cells
Indicates that the lymphocytes are fragile
Seen in:
Chronic lymphocytic leukemia (CLL)
What conclusion is to be made from seeing blasts, immature cells (ex. lymphoblasts, or myeloblasts) on peripheral smear?
ALWAYS abnormal finding
-suggests malignant hematologic disorder
If you see reticulocytosis with anemia, what should you think?
- hemolysis
- blood loss
Anemia with normal reticulocyte count. What does this suggest?
substrate problem (ex. Fe deficiency, Vitamin B 12 deficiency)
or
Maturation problem (ex. myelodysplastic syndrome)
Corrected retic count
= reticulocyte% x (patient hematocrit/45)
If corrected is >3 =normal
If corrected is <2= inadequate
Clinical pearl to see if bone marrow is compensating for the anemia
retic count + hemoglobin = should be close 15
Ex. 6.4 + 8.2 = 14.6 [this is normal! bm is compensating for anemia]
Serum Iron (Fe)
amount of iron in blood, bound to transferrin
70% of total iron
Ferritin
Measure of stored iron
30% of total iron
Total iron binding capacity (TIBC)
-total potential space available on RBC for Fe to bind
Transferrin
-protein that binds to iron and transports to the bone marrow to be incorporated in hemoglobin
Transferrin saturation
Amount of transferrin available for binding mobile iron
Ex. will be very HIGH in hemachromatosis. Also elevated in hemolytic, megaloblastic, sideroblastic anemia.
<15% in Fe deficiency anemia
Normal is 20-50%
What is the most sensitive test to detect iron deficiency
Ferritin
What does a low ferritin ssuggest
Fe deficiency
What does a high ferritin suggest?
hemochromatosis
Acute-phase reactants
Ferritin - elevated with inflammation and infection, but not iron storage issue
Transferrin - decreased (negative acute-phase reactant) with acute inflammation. Can also be decreased if liver dx since transferrin is made in the liver
What is the best iron test for hemochromatosis?
Transferrin saturation
