Hematology Flashcards
Define Neutrophilia
Elevated neutrophils- caused by physical or emotional stress, myelocytic leukemia, inflammatory disorders
Define Neutropenia
Decreased neutropenia- caused by dietary deficiencies (B12 and B9), some overwhelming bacterial infections, viral infections, and radiation & chemotherapy
Define lymphocytosis
Elevated lymphocytosis- caused by chronic bacterial infections, viral infections, and lymphocytic leukemias
Define lymphocytopenia
Decreased lymphocytes- caused by immunodeficiency diseases and radiation therapy
Define monocytosis
Elevated monocytes- caused by chronic inflammatory disorders & TB
Define monocytopenia
Decreased monocytes- this is very uncommon
Define eosinophilia
Elevated eosinophils- caused by parasitic infections, allergic reactions, and Hodgkin’s lymphoma
Define eosinopenia
Decreased eosinopenia- this is very uncommon
Define basophilia
Elevated basophils- caused by myeloproliferative diseases
Define basopenia
Decreased basophils- this is very uncommon
What is the most common cause of atypical lymphocyte findings in a blood test?
viral infection
If you see an increase in neutrophils and a shift to the left what type of infection is this?
Bacterial infection
What type of infection decreases the number of neutrophils?
Viral
What is a shift to the left?
Any increase in the numbers of immature neutrophils observed in the peripheral circulation. Often indicative of acute infection or other causes of neutrophilia.
An immature form of neutrophil which is observed both within and outside of the bone marrow is known as what?
Band neutrophils- aka PMN leukocytes
Will we ever see any neutrophils that are less mature than band neutrophils?
No
What is megakaryopoiesis?
the production of thrombocytes (platelets)
What does granulopoiesis refer to?
The maturation of leukocytes that contain granules (eosinophils, basophils, neutrophils)
What are the 3 steps for evaluation of hematopoiesis?
Complete Blood Count
Reticulocyte Count
Bone Marrow Aspiration & Biopsy
What 3 tests from the CBC are redundant with one another? What are they measuring?
RBC, HGB, and HCT- all 3 tell us whether or not the patient has normal amount of RBCs in different ways
Which test of the CBC is most widely used to evaluate a patient for anemia? What does this measure?
Hemoglobin concentration (HGB) This measures the weight of hemoglobin in blood
What is Packed Cell Volume also known as?
Hematocrit
What are other names for bone marrow?
Myeloid
Myelogenous
Intramedullary tissue
What is hematopoiesis?
The formation and development of ALL types of blood cells from their parental precursors
What is the very first blood forming organ during human development?
The yolk sac (during the first trimester)
After the first trimester, what organs take over blood formation?
Liver & spleen- then about hallway through pregnancy, the bone marrow takes over
True or False- Full grown adults produce blood primarily from the bone marrow of the axial skeleton?
True
The ratio of the volume of RBCs after centrifugation to that of whole blood is known as what?
Hematocrit or Packed Cell Volume
In a hematocrit test, what is a buffy coat?
the coating between the WBCs and RBCs due to the migration of the WBCs during centrifugation
What are the 3 clinical applications of altered RBC, HGB, and HCT?
Anemia
Erythrocytosis
Polycythemia
What does polycythemia mean?
Elevated blood cells including RBCs, WBCs, and platelets.
What does secondary polycythemia refer to?
Polycythemia that comes about as a result from another condition (hypoxia), example: smoking polycythemia, or living at high altitude, COPD
There is no increase in WBCs or platelets- it should actually be called secondary erythrocytosis
What 3 exams are included in an RBC indices?
Mean Corpuscular volume (MCB)
Mean Corpuscular Hemoglobin (MCH)
Mean Corpuscular Hemoglobin Concentration (MCHC)
What is MCV? (mean corpuscular volume)
the measure of intracellular volume of the average circulating RBC (relates to the size of the average circulating RBC)
What is the classic cause (definition) of microcytic anemia?
decreased MCV defines microcytic anemia
What is the classic cause (definition) of macrocytic anemia?
Increased MCV defines macrocytic anemia
What is the classic cause (definition) of normocytic anemia?
Normal MCV defines normocytic anemia
What defines anemia?
Decreased RBC, HGB, and HCT
What is MCH? (mean corpuscular hemoglobin)
the measure of the weight of hemoglobin within the average circulating RBC
- relates to the intensity of the coloration of the RBCs when stained with Wright stain on peripheral blood smear
What are the 3 categories of MCH?
Hypochromic RBC
Normochromic RBC
Hyperchromic RBC
What is MCHC? (mean corpuscular hemoglobin concentration)
the percent of the intracellular volume of the average circulating RBC that is hemoglobin- basically provides the same info as the MCH
What is the clinical application of the RBC indices?
Used to categorize the three main types of anemia
What would iron deficiency anemia present like with a CBC and RBC indices?
Decreased RBC, HGB, HCT
Decreased MCV, MCH, MCHC
= microcytic and hypochromic anemia
What would a B12 and Folate deficiency anemia present like with a CBC and RBC indices?
Decreased RBC, HGB, and HCT
Increased MCV, Normal MCH and MCHC
- macrocytic anemia
What would a chronic illness present like on a CBC and RBC indices?
Decreased RBC, HGB, HCT
Normal MCV, MCH, & MCHC
- normocytic and normochromic anemia
What is RDW?
Red Cell Distribution Width
- the index of RBC size differences, or the variability in RBC size populations
In health, what is the RDW?
There is minimal variation
When does an increased RDW occur?
Certain types of hematologic conditions–> anemia (can be early sign of anemia)
Increased RDW correlates with increased anisocytosis
When does a decreased RDW occur?
This is not observed
How is RBC morphology observed?
Microscopic evaluation of RBCs from a Wright stained peripheral blood smear
What are the most common RBC abnormalities?
Macrocytosis Microcytosis Hypochromia Polychromatophilia Poikilocytosis Anisocytosis
Define WBC count
The absolute quantification of the total number of circulating WBCs in a unit volume of blood
Defines the existence of leukocytosis or leukopenia
What is the Relative WBC differential count?
the relative percentage of each type of circulating WBC as determined by counting 100 WBCs on a stained peripheral blood smear
= the traditional method used during microscopic evaluation of RBC morphology
What is the Absolute WBC differential count?
Determined by either direct absolute quantification of each type of leukocytes via a modern hematology instrument- the more useful & accurate method
If the absolute WBC differential is not provided, how would you calculate it?
relative % x total WBC
What is a Platelet count?
the absolute quantification of the number of circulating thrombocytes in a unit volume of blood
- considered a hemostatic test not a hematologic test
Decreased numbers and/or function of platelets may result in what?
Platelet associated bleeding
What does platelet count tell you about platelet function
Nothing
What platelet count would indicate a risk for spontaneous bleeding?
40-50! In both conventional and international units
ex: 40-50 x 10 (to the third) mm (cubed)
What is MPV?
Mean platelet volume is a calculated index of the internal volume of the average circulating platelet= the size of the average platelet
What types of disorders might be seen with altered MPV?
Autoimmune disorders:
- systemic lupus erythematosus
- idiopathic thrombocytopenic purpura
- RA
- pernicious anemia
- some hematologic malignancies
- MPV is not imperative to ddx
Is the reticulocyte count a routine test or a special test?
Special test
What is a reticulocyte count most commonly used for?
To determine if the bone marrow is responding therapy in factor deficiency anemias such as iron, folate, and vitamin B12 deficiencies
Describe the timeline of RBC maturation
5-6 days from rubriblast to mature RBC
4-5 days within the bone marrow (intramedullary)
1 day in the peripheral circulation
Describe the relationship between anemia and the time of intramedullary maturation
The greater the degree of anemia, the shorter the time of intramedullary maturation
How do you calculate the reticulocyte % from the routin reticulocyte count?
of reticulocytes x 100
divided by
1000 RBCs observed
accepted reference range: 0.5-2.5%
What is bone marrow aspiraton and biopsy used for?
Rendering the definitive diagnosis in most myeloproliferative and lymphoproliferative disorders such as leukemia & other hematologic disorders
Who studies aspirated marrow?
by an MD clinical pathologist