Hematology Flashcards
____ are responsible for the production of myeloid and lymphoid cell lines.
stem cells
The lymphoid line leads to production of the _____, and the myeloid line is responsible for the production of ____
lymphocytes
- the remainder of WBC types,
- RBC and
- thrombocytes
Describe the progression of hematopoiesis
Stem cell–> Myelodi progenitor and lymphoid progenitor
-Myloid progenitor–> Megakaryocytes (–> thrombocyte/platelet), reticulocytes (–> erythrocyte), myelobast (–> Neutrophils, basophils, eosinophils and monocytes)
-Lymphoid progenitor–> lymphoblast–> lymphocyt
Notice that the reticulocyte ___ the erythrocyte, and all of us have a small percentage (~___%) of these in our peripheral blood under normal conditions
precedes
(<2%)
*Higher percentages of reticulocytes will make it out into peripheral circulation under high demand situations.
the preceding cell to the thrombocyte, or platelet, is the___. We won’t have these circulating in the periphery, but in times of high demand, the ___ will break down into larger, immature ___
megalokaryocyte
megalokaryocyte
platelets
CBCs is full of helpful information with regard to
- BM function
- renal fxn
- nutrition
- hydration status
- infection response
Describe a methodical approach to CBCs with anemias
- look at at cell lines, (WBCs, RBCs and platelets) as an evaluation of the patient’s bone marrow and RBC’s provide a look at renal fxn
- look at Hgb and Hct
- MCV (mean corpuscular volume)
- Peripheral blood smear for abnormal shapes of RBC’s, evaluate an increased number of WBCs, or in the case of lymphoblastic leukemia, lymphoblasts may be present in the peripheral blood
Patients can have a normal RBC count, but if the cells are poorly configured, such as in a hemoglobinopathy, or an iron deficient state, then the amount of hemoglobin in those RBC’s will be ____
low
___ often mirrors ___
hematocrit
hemoglobin
*i.e. if the hemoglobin is low the hematocrit is low
The hematocrit represents ___
the percentage of the whole blood that consists of RBC’s with their hemoglobin.
In patients with iron-deficiency anemia, the Hgb, Hct, and RBC will be ___
- Hgb will be low,
- Hct will also be low because the RBC’s are smaller due to the smaller hemoglobin, and
- therefore the RBC’s are taking up less space in the whole blood.
in an iron-deficient patient who also has acute dehydration, the Hgb and Hct will be __
- Hgb will still be low but
- the Hct may be normal
*due to the decrease in overall blood volume from the dehydration
Causes of leukocytosis (increased WBCs)
- Platelet clumping/lab error
- Acute infection
- Chronic Inflammation (JIA, Kawasaki)
- Down Syndrome
- Chronic myelogenous leukemia (CML)
- Recent steroid use (40mg/d +)
*In primary care, we look at WBC almost exclusively as an evaluation of fever
Recent high dose steroid use causes ___ so that more are present in the periphery
demargination of WBCs,
Causes of leukopenia (low WBCs)
- Post-infectious bone marrow suppression
- HIV, Parvovirus, EBV, CMV , Varicella - Bone Marrow Failure- Aplastic anemia or leukemia
- Cyclic neutropenia- occurs every 21 days
- Autoimmune neutropenia
- African ancestry
Causes of post-infectious bone marrow suppression that lead to leukopenia
- HIV
- Parvovirus
- EBV
- CMV
- Varicella
Causes of thrombocytosis
Almost exclusively reactive:
- Infection
- Kawasaki syndrome
- Inflammatory/Autoimmune Disorders
- Trauma
- Post-steroids
Causes of thrombocytopenia
- Immune thrombocytopenic purpura (ITP)
- Viral suppression of platelet production
- Bone marrow failure- ALL, CML, aplastic anemia
- Thrombocytopenia of the newborn
Other causes of unusual bleeding:
- Inherited bleeding disorders-Factor deficiencies (hemophilia), Von Willebrand
- Acquired bleeding disorders- DIC, Liver dz, Vit K deficiency
- HSP
What should you do when you find thrombocytopenia in a patient, if they are not having problems with bleeding in the form of nosebleeds, petechial or purpuric rashes?
no further investigation is usually warranted