Hematology Flashcards
Basic Hematology is the
STUDY OF FORMED ELEMENTS OF BLOOD AND BLOOD FORMING TISSUES
- screen, diagnosis, monitor hematologic diseases to give overall health idea
What is the composition of blood?
6-8% of total body weight & equals approx. 5 liters
Serum vs. Plasma
Both fluid portions
Plasma
From ANTICOAGULATED BLOOD
- HAS CLOTTING FACTORS
- MAKES UP ABOUT 45-60% OF BLOOD’S VOLUME
Serum
FROM CLOTTED BLOOD
- HAS NO CLOTTING FACTORS
- (USED UP IN THE CLOTTING PROCESS)
Cellular elements
remainder of BV
- Erythrocytes/RBCs 4/6 million
- transport O2 & carbon dioxide
Leukocytes/WBCS
- 4800-10,800 in blood, many more in tissues
- IMMUNITY, defend against bacteria, viruses, all foreign materials (includes, allergens like pollen)
What are some specific tests?
CBC, ESR (erythrocyte sedimentation rate), glycosolated Hemo (HgB A1C), Hemoglobin Electophoresis, Tests of coagulation
Specimen Collection
Venipuncture using a 22 gauge needle or larger
Lavender usually anticoagulant hema tube.
Blood for a CBC should be fresh,
< 3 hours
In infants and pediatric patients, a CBC may be collected through a heelstick
CBC consists of
White Blood Cells (WBC) Red Blood Cells (RBC) Hemoglobin (Hgb) Hematocrit (HCT) Mean Corpuscular Hemoglobin (MCH) Mean Corpuscular Hemoglobin Concentration (MCHC) Mean Corpuscular Volume (MCV) Red Cell Distribution Width (RDW) Platelets (PLT)
WBC
White Blood Cells or Leukocytes are cells produced by the immune system and defend against infection/foreign materials.
Produced by the bone marrow.
There are 5 types of leukocytes - neutrophil, eosinophil, basophil, lymphocyte, monocyte.
Average cell life of 3-4 days.
Leukocytosis: elevation in leukocytes above the normal range. (mostly due to neutrophil increase)
Leukopenia: decrease in leukocytes from the normal range.
What are types of granulocytes?
Neutrophils->Acute bacterial, inflammation
Basophils->Rare allergic reactions
Eosinophils->Asthma/allergies/parasitic
Lymphocytes are for
Acute viral, certain bacterial
Lymphoma, leukemia
Monocytes are for
CHRONIC INFECTIONS
WBC & differential
LAVENDER TUBE
Normal Adult: 4.5-11.0 x10 3rd/mm3
Breaking It Down (Differential)
Manual Differential Count:
Smear is scanned under low power magnification, fair cell distribution is found, examined under oil immersion magnification
Automated count:
Use laser light beam, low and high angle light, and analysis of volume
Ranges are affected by age
Useful to diagnose infection, inflammatory disorders, malignancies, drug effects.
Neutrophils (PMN)
Predominant White Blood Cell (40-76% of cells in humans)
Defend against bacterial and fungal infection. They are the “first responders” to infection.
Active and dead neutrophils in large numbers form PUS.
Average life cycle of 5 days. Cells die after phagocytosing a few pathogens.
Neutrophils have a multilobed nucleus that may appear like multiple nuclei. The degree of nuclear lobulation indicates cell age.
Shift to the LEFT means
predominance of immature cells (one or two nuclear lobes) separated by a thick chromatin band.
Common reasons for a left shift include: bacterial infection, toxemia, hemorrhage, myeloproliferative disorders
ACUTE!.
Shift to the right means
predominance of cells with four nuclear lobes.
Common reasons for a right shift include: liver disease, megaloblasticanemia, iron deficiency anemia, glucocorticoid use, stress reaction.
CHRONIC
Eosinophils
Bi-lobed Nucleus Age Dependent = 0-450 Lifetime of 8-12 days Elevated in parasitic infections and allergies PARASITIC INFECTIONS AND ALLERGIES (such as asthma, hay fever and hives). Make up 1-3% of leukocytes.
Basophils
Commonly elevated in allergic and antigen responses.
Release the chemical HISTAMINE resulting in vasodilation.
Bi or Tri-lobed nucleus.
Lifetime of a few hours to a few days.
Make up <1% of leukocytes.
0-1%
Lymphocytes
More common in the lymphatic system. Have a deep staining nucleus. Make up 24-44% of leukocytes. There are three types of lymphocytes: -T cells -B cells -Natural Killer Cells Lymphocyte subsets are useful in the diagnosis of HIV/AIDS and various types of leukemia/lymphoma.
B cells
make antibodies that bind to pathogens to enable their destruction.
T cells
CD4+ T cells
CD8+ cytotoxic cells
CD4+ T Cells
the helper cells. They bind antigens to the surface of cells, activating B cell antibodies to destroy the cell.
used in acute HIV infection to identify an individual’s immune response.
CD8+ Cytotoxic Cells
able to kill virus infected or tumor cells.