Hematologic System (week6) Flashcards
Leukemia
a. type of cancer of the hematopoietic system in which there is uncontrolled proliferation of leukocytes, causing over-crowding of bone marrow & decreased production of normal
hematopoietic cells
b. S&S
1) leukocytosis; ex. of a WBC count you might see on a blood test– 50,000 (norm count = 6 to 10,000)
2) thrombocytopenia-> easy bleeding & bruising
3) anemia-> fatigue, SOB.
4) ease of infection because the WBC immunocyte function is impaired.
- classified according to predominant cell (myeloid vs lymphoid) and the onset (either acute or chronic)
Multiple myeloma
- overview
a. a type of cancer that is mostly idiopathic etiologically, but also may have genetic component
b. predominant cell involved in becoming cancerous is B-lymphocytes, specifically the plasma cells.
- pathogenesis
a. normally, plasma cells (the cells that develop from B-cells and secrete immunoglobulins) selectively produce immunoglobulins
on as-needed basis.
b. with multiple myeloma, some of the plasma cells become malignant and begin overproducing immunoglobulins.
c. these immunoglobulins infiltrate bones (and certain organs as well, but mainly bones), causing multiple malignant tumors that increase osteoclastic activity
1) remember that osteoclasts are hematopoietic cells that normally migrate along bone capillary walls and “chew up” bone cells when calcium is needed in the body
2) in multiple myeloma, osteoclasts go into overdrive and chew up more bone cells than normal
3) thus the bones get weaker & there is a pathologically high
amount of calcium in the blood (hypercalcemia).
- S&S / tx
a. osteoporosis, which leads to pathological fractures (bone breakage that occurs with minimal stimulus).
b. hypercalcemia with its S&S of confusion, lethargy, weakness, kidney stones & kidney failure
e. tx – chemotherapy, radiation, bone marrow transplantation
anemia
- overview
a. anemia definition
1) anemia = less than normal number of total circulating erythrocytes and /or a decrease in the quality or quantity of Hgb.
2) anemia is the RESULT of a disease processes; it is a “state” or “condition,” and/ or can be considered a SIGN of a disease, but only in certain cases is it considered a disease process
in itself
b. general etiologies; anemia can be a result of disorders that precipitate a:
1) decrease in erythropoiesis, such as bone marrow dysfunction, leukemias, or hypersplenism.
and/or
2) loss of RBCs via hemorrhage and/or pathologic hemolysis
c. classifications of anemias are according to the changes in shape, substance, or size of RBC
1) shape— there are several anemia disorders which are caused by abnormalities in shape; ex– sickle cell anemia
2) substance—if there is reduced hemoglobin content, an anemia may be classified as hypochromic—ie, less “color”
3) size– microcytic (“tiny cell”), normocytic, or macrocytic (“big cell”) anemias.
anemia S&S
S&S of most types of anemia, in general:
a. fewer and/or deranged RBCs or Hgb means disruption in the effectiveness of O2 getting to cells of our tissues & organs for use in cellular metabolism
b. therefore, an anemic patient will usually have S&S related to hypoxemia (lack of oxygen in the blood)
c. these S&S can be
1) slow & subtle if there is slow process & body is able to compensate
or
2) immediate and severe if cause is sudden
d. reduced blood O2 (hypoxemia) -> tissue hypoxia ->
1) SOB
2) weakness & fatigue, muscle cramps
3) CNS effects: slowed mentation, dizziness, lethargy, syncope (fainting)
4) pallor of the skin because less RBCs traveling in skin capillaries – less pinkness of the skin
- diagnosis of an anemia AND its classification by a blood test called a CBC (complete blood count)
a. steps in classification according to RAW NUMBERS & SIZE of cell:
1) first look at RBC count–normal is 4 to 6 million/L (males); patient has anemia when the RBC count is <4 million.
2) to NAME the type of anemia, next look at the MCV (mean corpuscular volume), which is the size of each RBC; normal range = 80 to 95
a) pt. has microcytic anemia when the MCV is
<80.
b) pt. has normocytic anemia when the MCV is
in normal range.
c) pt. has macrocytic anemia when the MCV is
>95.
b. other numbers you might see in an anemic person’s CBC:
1) low hemoglobin (Hgb); normal Hgb = 14-18 gm / L, so < 14 may be seen in anemia.
2) low hematocrit (Hct) – the percentage of RBCs in the blood; normal = 42 to 52%, so < 2% may be seen in anemia.
microcytic anemia
1) an anemia in which the size (MCV) is smaller than normal, so CBC would show RBCs of <4
million__ and MCV of <80.
2) patho:
a) something causes the body to slowly, chronically, lose RBCs and thus it begins to “run
low” on material to make enough full-sized replacement RBCs
(1) so over period of time, the bone marrow tries to “catch up” by churning out RBCs that are smaller (less mature).
(2) this compensatory response is not enough to bring the RBC numbers up all the way to normal, but it is better than nothing.
b) examples of chronic, steady loss of RBCs: (1) women with heavy menses
(2) occult (hidden) GI bleeding
c) sometimes microcytic anemia is called “iron deficiency anemia” because iron (Fe) is an essential part of the Hgb molecules which are lost with the RBCs.
3) S&S of microcytic anemia
a) in common with MOST anemias are: RBC <4million, fatigue, weakness, sometimes SOB
& dull mentation.
b) particular to its classification you would also see low MCV & low Hgb_.
4) treatment—stop blood loss if possible and give iron supplements
normocytic anemia
1) an anemia in which the size of the RBC is normal, so CBC would show RBCs of <4 million
and MCV that is normal.
2) patho; two possibilities:
a) something causes RAPID blood loss, so that there is no time for compensatory response of smaller RBCs; ex—traumatic hemorrhage.
OR
b) a chronic disease cause a slow-down in production of RBCs—they get produced in their
normal size, but just more slowly & in less numbers; ex– AIDS, lupus, chronic renal failure
3) S&S of normocytic anemia
a) in common with MOST anemias are: RBC <4million, fatigue, weakness, sometimes SOB
& dull mentation.
b) particular to its classification you would see normal MCV.
4) treatment
a) for acute blood loss– stop blood loss if possible and give units of blood as needed to replace.
b) for chronic disease– give a type of growth hormone called erythropoietin to stimulate bone marrow to make more RBCs.
macrocytic anemia
1) an anemia in which the size (MCV) is larger than normal so CBC would show RBCs of <4
million and MCV of >95 .
2) patho:
a) certain disease processes cause faulty DNA coding of RBC size so that the RBCs are
larger than normal (but don’t function right!)
b) most common example of a macrocytic anemia is pernicious anemia.
(1) mostly seen in the elderly, in patients with GI absorption disorders, and in people with inadequate nutrition (eg, alcoholics)
(2) often begins with diminished production of intrinsic factor, a hormone made by parietal cells in stomach.
(3) without intrinsic factor, vitamin B12 cannot be adequately absorbed from digested food
(4) without vitamin B12, DNA malfunctions & makes coding error in RBC creation-> too few RBCs made AND they are larger than normal (but don’t function right!).
3) S&S of macrocytic anemia
a) in common with MOST anemias are: RBC <4 million, fatigue, weakness, sometimes SOB & dull mentation.
b) particular to its classification you would see
(1) MCV >95.
(2) glossitis (“inflammation of tongue”) swollen, beefy red, smooth, painful tongue
(3) neuropathies, most often of the legs, such as paresthesia
(a) often described as “pins and needles” or burning
(b) caused from lack of B12 as an important nerve modulator
4) treatment—usually B12 as an injection.
frank or occult bleeding
a. frank bleeding (“frank” = obvious or easily visible); examples:
1) under the skin:
a) petechiae – pinpoint red spots that don’t blanche
b) purpura – larger areas that look purplish
c) ecchymosis—general term for collection of blood under skin greater than~1cm
2) GI bleeding—stools can be bloody or black and tarry_.
3) mucous membranes especially may begin to bleed; ex—nose bleeds
b. FYI: occult bleeding – “hidden” bleeding; ex– in GI tract if the bleeding is slow & not in areas where blood can be digested, stools may appear normal but actually have blood in them.
- two subcategories of clotting deficiency—platelets & factors
a. platelets (AKA thrombocytes) deficient in number—
thrombocytopenia
1) causes
a) congenital problems (rare)
b) nutritional
c) certain drugs & chronic diseases
d) autoimmune:
(1) IgG attacks platelets, diminishing their
effectiveness
(2) called idiopathic thrombocytopenia purpura –ITP
2) S&S
a) usually platelet count on CBC is less than 100,000 (normal is between 150,000 – 400,000)
b) bleeding as noted above.
hemophilia
—refers to several possible different hereditary
deficiencies of coagulation factors, usually X-linked recessive problem
a) S&Ss— spontaneous bleeding or bleeding that is out of proportion to amount of trauma
b) txs:
(1) transfuse plasma—plasma has clotting factors
(2) transfuse concentrates of whichever clotting
factor is deficient.
von Willebrand disease (vWD)
a) von Willebrand Factor (vWF) is found in the blood and in the tissue in various forms.
(1) one example—a type of vWF is released by
injured tissue
(2) it “calls” platelets and binds to them and to
fibrinogen to promote clotting—a “platelet plug.”
b) vWD, like hemophilia, is an inherited disorder & it is the most common clotting disease – every 1 in 100 person has a variation of it.
c) S&S—various types of vWD cause varied severity of S&S
(1) mostly very mild clotting deficiency with mild incidences of “easy bleeding.”
(2) ex—some women manifest very heavy periods due to a type of vWD.
d) tx—usually none needed, or symptomatic; certain more severe forms receive transfusions of vWF.
liver disease (such as cirrhosis)
a) liver is site of protein synthesis, including coagulation factors
b) liver disease -> coagulation factors -> decreased ability to clot -> easy bleeding.
thrombocytosis
platelet count greater than 400,000
a. can be from a genetic myeloproliferative disorder or from secondary cause such as RA, cancer, or after splenectomy
b. causes hypercoagulation which can manifest as thrombotic disorder– proliferation of blood clot formation
thromboembolic disorders
any combination of thrombocytosis and
clotting factor overactivity.
a. thrombus – an arterial or venous clot attached to vessel wall
b. embolus— an arterial or venous thrombus that has broken loose and travels in the circulatory system.
Splenomegaly
enlargement of spleen
1. causes can be categorized as hematologic, infectious, malignancies,
or physiologic:
a. hematologic: any time there is increased hemolysis of RBC’s,
the spleen can enlarge because it has more RBC “debris” to
process; examples:
1) Rh blood type incompatibility (erythroblastosis fetalis)
2) ABO blood type incompatibility
3) hemolytic problems from:
a) drug reactions and autoimmune diseases in which
there is a triggering of antibody attack on RBCs
b) infections in which RBCs are attacked, such as
malaria
b. infection/inflammation
a) viral –hepatitis, mononucleosis (Epstein-Barr virus), CMV
b) bacterial– TB
c. malignancies, especially leukemia; huge numbers of WBCs
come through spleen & it swells.
d. physiologic splenomegaly—usually an individualistic quirk;
idiopathic etiology & no S&S.
2. S&S of splenomegaly:
a. palpably large spleen (normally you can’t palpate it)
b. may have pain
c. may have hypersplenism.
