Chapter 12 Flashcards
1
Q
Define the term Hematology
A
study of blood.
2
Q
When blood is seperated by centrifugation, what are they two fluid compenents?
A
- plasma- complex mixture of water, proteins, carbohydrates, lipids, electrolytes and clotting factors
- Cellular components- RBC, WBC, and platelets.
3
Q
Which organ is the principal site of blood cell formation
A
bone marrow
they contain precurors of developed cell lines [RBC, WBC and platelets], which multiple and mature.
4
Q
Define the term hematopoiesis
A
the term given to the production of blood cells. `
5
Q
what happens to bone morrow as peoeple age?
A
the number of bone caivities containing red marrow decrease but the increased size of the hemopoeitic marrow site found in the vertebare, sternum, ribs, skull and pelvic bones compensates.
6
Q
what is the name of the stem cells that become commited to production of RBC
A
erythroblasts,
they undergo 4 miotic divisions eventially producing 16 RBC (erythrocytes). When releasted into the system its called retibulocyte.
7
Q
What is the principal factor in the regulation of RBC production?
A
the hormone erythropoietin which is produced by the kidney. This hormone [ ] is ^ when O2 transport to the tissues is impaired, and it causes stem cells to commit to RBC line and increase rate of cell dividsion.
8
Q
What is the life span of a normal RBC?
how does it die?
A
120 days,
it is removed by the reticuloendothelial system which is composed of spleen, liver, bone marrow and lymph nodes.
9
Q
how are RBC’s destroyed in the bone morrow?
How are misshapen cells removed?
A
special cells called macrophages, they engulf or phacocytize the aging RBC in the bone marrow. the hemoglobin molecule is broken into iron, protoporphyrin and globin.
- by the spleen
10
Q
When protoporphyrin undergoes further degradation, it eventually becomes what?
What happens to the iron?
A
bilirubin
reincorporated into newly synthesized heme or is store for future use.,
11
Q
What is the most useful laboratory test for the evaluation of hematological processes and disorders?
A
the complete blood count. used as a diagnostic monitoring prognosis test treatment evaluation screening test.
12
Q
The CBC consists of two parts, what are they and what to they include?
A
- hemogram
- WBC, RBC, HGB, HCT, (MCV, MCH, MCHC), PLT - second part
- WBC differential and RBC morphology
13
Q
define leukocytosis and leukpenia
A
increased number of WBC and decreased number of wbc
14
Q
name 3 causes of leukocytosis
A
- acute bacterial infection
- physical stimuli such as heat, cold, pain, sugery, malignancy
- emotional stimuli such as stress
15
Q
What is leukemia?
A
elevated WBC count is permanently elevated and progresive
16
Q
When is leukpnia seen?
A
with viral or rickettsial infection or with an overwhelming bacterial infection
17
Q
what is anemia
A
a decrease in the number of circulating erythrocuts and/or the quality of these cells.
18
Q
what causes anemia?
A
- decrease in RBC production or reduction in hemmoglobin level
- an increase in RBC destruction
- dietary insufficiencies
- actual blood loss
19
Q
What is polycythemia?
A
increase in RBC
20
Q
the oxygen-carrying capacity of blood is directly proportional to what?
A
the hemoglobin concentration rather than the number of RBC.
21
Q
What causes decreased hemoglobin levels
A
anemia, hyperthyroidism, liver cirrhosis, severe hemmorhage, hemolutic reaction, and cancer.
22
Q
When do you see increased hemoglobin level
A
polycythemia,
pulmonary disorders
congestive heart failyre
23
Q
What is hematocrit?
A
is the volume of erythrocytes compared to the colume of whole blood in a sample.
it means to separate blood and is calculated as the height of the packed cells compared to the total height of the specimen after blood is centrifuged then is expressed in a percentage
24
Q
How are the red blood cell indices (MCV, MCH, and MCHC) calculated?
A
determined from the same blood sample used for the RBC count, hemoglobin and hematocrit values.
they are used to define cell size and hemoglobin content.
25
When are microcytic cells seen?
in iron deficiency anemia and thalassemia
26
When do macrocytes apepar?>
liver disoders, alcoholism, folic acid and Vit 12 deficiencies.
27
What is MCH?
the average weight of hemoglobin in each individual RBC
28
What is MCHC?
a measure of the average concentration of hemoglobin in RC.
29
Define differential
in a blood sample 100 consectutive WBC are taken which contain the 5 types of normal leykocytes and any abN cells are collectected and compared as a percentage. The ration can help determine certain disorders
30
Define normocytes
normal sized erythrocytes,
| they are uniform, circular, homogenous discs.
31
what are microcysts and macrocytes?
cells smaller than 6 mircons and cells larger than 8 microns.
32
Define the term Anisocytosis
describe an abnormal variation in cell size.
33
Define the term poikilocytosis
variation in red blood cells.
34
define the term schistocytes
cell fragments.
35
What should be considered by u/w when intepreting the CBC?
1. couse of CBC results
2. reason the test was done
3. age of the results
4. whether a dx has been made
5. is there a pattern to the results over time?
36
What part of the CBC numbers should be analyzed with anemia hx?
hemoglobin, MCV and MCH.
| Used to classify the anemia as normocytic, microcutic or macrocutic and normochormic of hypochornic
37
What are nomoccytic and normochromic anemias?
those with normal MCH and MCV values.
| 1. chronic disease, acute blood loss, and aplastic anemia anemias with decreased MCV and MCH are almost a
38
what are the characterisitics of iron decificency anemia and thalaseemia?
1. decrased MCV and MCH (microcytic, hypochromic)
| 2. very low MCV
39
What are the characterisitics for folic acid deficiency, Vit B 12 deficiency, or a problem with intrinsic factros that transport VB12 to the intestine.
Elevated MCV (macrocytic)
40
What are some sxs of anemia progreassion
1. fatigue, malaise, dyspnea an exertion, and headaches, faintness and vertigo.
the skin, eyes, tongue, lymph nodes, sleep, liver and nervouse sxs provide clues to the potential dx.
41
What other tests besides CBC can aid in the dx of anemia
reticulocyte count, blood volume studies, stool for occult blood, serum iron, ferritin, totoal iron binding capacity, VitB12 and folic acid levels and bone marrow aspipration and examination.
42
Anemia can be classified in two different manners. What are they :?
1. morphologic classification: based on microscopic observations. 3 groups
a) normocytic/normochromic anemia
b) microcutic/hypochormic anemia
c) macrocytic anemia
2. pahtophysiologic clafficication: based on cause
a) blood loss anemia
b) anemia d/t decreased production
c) anemia d/t desctruction
43
What is the most common cause of anemia?
IDA.
- common in females, and those with poor diets.
-
44
IDA can be described in a 3-stage process. Please define this/
1. storage iron is decreased or absent while serum iron levels and hemoglobing and hematocrit levels are normal. -AKA iron depletion
2. low serum iron concentration wihtout the presence of anemia occurs. This is called deficiency without anemia
3. iron deficiency anemia, which is characterized by decreased serum iron, hemoglobin and hematocrit occurs. `
45
Megaloblastic anemia is an imprecise term used to designate a group of anemias that have smiliar characteristics of morphology and funciton. define theses
. here the DNA and RNA synthesis is impaired- results in fewer but larger RBC and macrocuyic anemia.
A dificiency in VB12 and folic acid results in magaloblastic changes.
- decreased VB12 interferes with myelin synthesis = neurological sxs
46
define pernicious anemia
autoimmune disorder that causes a lack of intrinsic factor.
| - thought to be caused by abx directed agasint the mucosal cells of the stomach that produce the intrinsic facor.
47
What is Aplastic anemia?
a bone marrow disorder characterized by a reduction of hemopoietic tissue, replacement of hemopoietic tissue and depletion of all cell lines .
- most commonly causes benzene exposure and recent use if INH for TB.
- presents with pancytopenia
48
What is pancytopenia
a hypocellular bone marrow, and no abN cells in the peripheral blood.
49
Define Pure Red Cell Aplasia
similar disorder to aplastic anemia only the RBC precursors are hypoplastic.
- can be acquired or a congenital disorder.
50
How are those dx with aplastic anemia treated?
since sxs are rare, those usually have late progression of the disease prior to treatment. tx includes transfision of blood compoenents and possible bone marrow transplantaiton
* disease hass a poor progression.
51
Define the term hemolytic in hemolytic anemia.
its a process defines as a situtation in which there is shortened RBC survival.
- can be d/t intracorpuscular or extracorpuscular defects.
52
Give some examples of intracorpuscular and extracorpuscular defects.
1. intra: hereditary and results from abnormalities of the cell membranes, hemoglobin molecule or enzymatic defects.
2. extra: aquired and caused by immune and nonimmune mechanisms, infections or severe burns.
53
Define Hereditary spherocytosis, include sxs and tx
- most common group of hemolytic anemias involving the cell membrane
- RBC become sphere-shaped and are destroyed in the spleen.
- sxs of jaundice.
- tx with splenectomy, risk of mortality is related to infection from no spleen.
54
Define G-6-PD (glucose-6-phosphate dehydrogenase) deficiency
- hereditary X-linked recessive abnormalitiy in which the activity or stabiloity of the enzyme G-6-PD is markedly diminishes.
- results in hemolytic anemia following administration of oxidant drugs, during infection, during stress, fava beans or inhallation of pollen.
- tx with avoiding oxidant drugs.
55
Define hemoglobinopathies
hereditary disorders involveing the polypeptide chains of the glocin portion of the hemoglocin molecule resulting in hemolytic anemias. The normal hemoglobin is A.
- there are 4 abN hemoglobings: S, C, D, and E.
56
Define Sickle cell disease
homozygous hemoglobin S causes sickle sell
- chronic hemolytic anemia manifested in childhood.
- black population
- when O2 decreases abN hemoglobin molecule polymerizes into crystals. they deform the cell into a sicle shape that cant pass through the capillary sys.
- dx with hemoglobin electrophoresis
-
57
What is thalassemia?
caused by decreased synthesis of 1 of the polypeptide chains that make up hemoglobin > ineffective RBC production
- homozygous form is called thalassemia major
- heterrozygous form is thalassemia minor
- dx with hemoglobin electrophoresis
- characterized by decreased production of beta chains.
- tx is only suppotive with blood transfusions, folic acid administration and spleenectomy.
58
whats another name for Cooley's anemia?
| what is beta thalasemia trait?
Beta thalassemia major
and
Beta thalassemia minor *most common.
59
define polycethemia
```
General term for 'many cells"
3 types:
1. polycythemia vera,
2. secondary polycythemia
3. relative polycythemia
```
60
define polycythemia vera
myeloproliferative disorder of the bone marrow that can terminate in acute granulocytic leukemia.
- ^ in RBC count, hemoglobin, hematocrit and RBC mass
- increased platelets > high incidence of thrombosis
- 30% will develop leukemia.
- tx- phlebotomy.
61
Define phlebotomy
the practice of drawing blood from patients
62
Define secondary polycythemia
usually d/t lack of O2 d/t hormonal problems.
Decreased O2 tension in lung increases erythropoietin production and subsequent RBC production
- can be caused by respiratory disorders, high altitudes, heart diseases characterized by a venoartrial shunt or valve disorder, certain renal/neoplastic disorders, and testosterone administration.
63
Define relative polycythemia
-dehydration can cause hemoconcentration with artificially increases RBC count.
sceen with vomitting, diarrgea, severe burns, stress, exercise.
- drug reactions can increase or decrease the eythrocyte count.
- smokers have elevated hematocrit levels.
64
What are the 5 types of normal Leukocytes?
```
neutrophils
eosinophils
basophils
lymphocytes
monocytes
```
65
Which Leucocytes are considered granulocytes?
Neutrophils, eosinophins and basophils
- originate from a common precursor stem cells.
- these cells are released to neutralize infection and foreign substances
66
Define Neutrophils.
- most numorous
- nucleous is pinched off segments connected by fine filament.
- fights bateria and inflammation by phagocytizing, neutralizing and destroying cells or can inertly digest them.
- increased bands > increases neutrophil release, where cells are premature, (like bacterial infection)
67
Define Eosinophils
- cytoplasm contains large granules that stain a bright-red-orange
- make up to 1-5% of leucokules
- cells have close relation to allergies, presece of allergic diseases increases # of cells.
- pronounced eosinophilia will occur in tissues invaded by parasites.
68
define BAsophils
- rare cells
- contains heparin and histamine and appears in allergic states, chronic granulocytic leukemia and following irradiation.
69
Define lymphocytes
- second most abundant
- majority of these cells are either T or B lymphocytes. Those influences by thymys are T cells, and those influenced by bursal equivalent are B cells.
- t cells function in Cell-medicated immunity, delayed hypersensitivity, graft rehection and defence against intracellular organisms
- B cells, function in humoral immunity or the production of antibodies.
70
What is reverse differential, in terms of WBC presence?
when the number of lymphocytes exceeds the number of neutrophils in the differential.
71
Define lymphocytosis
increased number of lymphocytes
- occurs when blood shows neutropenia
- present with bacterial and viral infection, acute infection recovery and with CLL
72
What is infectious mononucleosis?
common disorder caused by EBV (virus).
| sxs: fatigue, sore throat, swollen lymph glans, and fever.
73
Define monocytes:
-largest cells of normal blood
- migrates to the tissues with it functions are macrophages.
- they ingest and destroy particles, debris and bacteria.
-
74
when do you see monocytosis?
recovery stage of acute infections and with hematologic diseases, lymphoma, and monocytic or granulocytic leukemia.
75
Define Leukemia
- malignant disorder characterized by the uncontrolled proliferation of one or more types of immature or abN leukocytes.
- categorized based on presence of immature cells.
acute: prdominance of immature cells, chronic= proliferation of mature looking cells
76
There are 4 kinds of common leukemias. Define the following
1. Acute lymphocytic leukemia
2. Chronic Lymphocytic Leukemia
3. acute myelogenous leukemia
4. chronic myelogenous leukemia.
1. most common in children and is curable
2. disorder of morphologically mature but immunologically immature lymphocytes. Manifested by the progressive accumulation of these cells.
3. characterized by the presence of myeloblast in the peripheral blood. 60-70% cases have complete remission
4. one of the myeloproliferative disorders. Gradual onet at older ages and is not curable with chemo.
77
Define platelets (thrombocytes)
- smallest blood cell
- in peripheral circulation there are represented with punched of portions of megakaryocyte.
- non-nucleated, round or oval disc shaped structures
- responsible for preservation of capillary integrity and coagulation
- 2/3 in blood, 1/3 of supply in spleen
- average life span 7.5 days.
- average coutns 150K to 350K per cubic meter.
78
What are megakaryocytes
large, multinucleated cells found in bone marrow.
| 1 cell can release several thousand plateletes.
79
Abnormally increased numbers of platelets as seen with thrombocythemia and thrombocytosis occur how?
```
cancer,
chronic myelogenous leukemia
polycythemia vera
acute infections
trauma
and following splenectomy.
```
80
What is the term given to decreased platelet counts and are seen when?
thrombocytopenia
seen in idiopathic thrombocytopenic purpura (ITP) hemolytic, aplastic, or pernicious anemia, during cancer therapy and from drug toxitiy.
81
T or F. Aspirin has been used therapeutically as an anti-platelet agent to prevent thrombosis in heart patients?
yes
| it can affect platelet function.
82
What is ITP?
a disorder of unknown cause characterized by marked thrombocytopenia and large skin discolorations due to subcutaneous hemorrhages.
83
Define Hemostasis
Prevention of blood loss through several hemostatic mechanism.
1. response to injury >vasocontriction d/t platelets releasing serotonin. Expoased collagen fibers from the injury >cause platelets to adhere > ADP release> platelets to aggregate. these then form a pletelet plug. Coagualtion factors in the plasma and form the platelets initiate a cascade of reations leading to > fibrin clot. This clot is essential for sustained hemostasis.
84
Name the several common laboratory tests that can be used to monitor anticoagulant therapy to make a dx of factor deficiency.
1. prothrombin time
2. activated partial thromboplastin time
3. international normalized ratio.
85
Name common anticoagulants that are used for treatment options.
heparin and coumadin*
*impairs the synthesis of Vit K which is needed for production of Factors 2, 7, 9, 10.
86
Coagulation disorders can involve a number of the factors of blood coagulation. Name 3 examples.
1. defects in the ability of platelets to function thus leading to aggregation disorders.
2. deficiency or inactivity of coagulation factors causing a break in the cascade chain
3. defects in which the system overreacts, resulting in a hyper coagulable state.
87
What causes Hemophilia A?
1. inherited disorder, x-linked recessive, which causes deficiency of Factor 8.
88
What causes Hemophilia B (christmas disease)?
What does it do>
- lack of factor 9. These pt have the initial plug formation but lack the ability to develop a fibrin clot. This causes persistent bleeding.
- any organ in the body can be a site of bleeding with hemmorhage having a lethal potential
89
Recurrent hemarthrosis results in what?
joint damage,
90
Define Von Willebrand's diseaSe, also called pseudohemophilia.
- hereditary disorder of hemostasis transmitted as an autosomal trait.
- characterized by long bleeding time.
- involves both platelet and factor 8 deficiencies results in problems of plate adhesion and fibrin formation.
- bleeding is usually mucosal and cutaneous.
- more common in F.
91
Define Hyper-coagulable state
- when the body does not urn off the coagulation functions. This leads to ^ risk of TIAs and CVAs, and retinal infarcts, DVT and pulmonary emboli.
- the breaking systems in place to prevent the cascade process following injury (clotting) as well as inappropriate clot formation are impaired.
92
What proteins and cells form the clot breaking system?
plasmin, antithrombin 3, protein C and protein S
93
Name some-conditions that cause a hyper-coagulable state
1. presence of antiphospholipid antibodies- including lupus anti-coagulants and anticardiolipin antibodies- cause thrombosis in arteries or viens
2. presence of Factor 5 Leiden, (mutation) ^ blood tendency to clot- hereditary disorder
*tx'ed with aspirin or Coumadin to eliminate recurrent DVT
