EXAM I Hematology Flashcards
___ is the study of blood and blood-forming tissues (bone marrow, spleen, lymph system)
hematology
what are the components of blood?
- plasma - 55%
- blood cells - 45%
- three types - erythrocytes, leukocytes, thrombocytes/platelets
erythrocytes are composed of ___
hemoglobin
___ = erythrocyte production, is stimulated by ___, and is controlled by what hormone?
- erythropoiesis
- hypoxia
- erythropoietin synthesized in the kidney
___ = destruction of erythrocytes
hemolysis
during hemolysis, ___ is released into the blood stream
bilirubin
what is the normal life span of a erythrocyte?
120 days
what are the 5 types of leukocytes?
basophils, eosinophils, neutrophils, monocytes, lymphocytes
which type of granulocyte functions in phagocytosis and early phase of inflammation?
neutrophil
which type of granulocyte functions in phagocytosis and parasitic infecitons?
eosinophil
which type of granulocyte functions in the inflammatory response and allergic response?
basophil
which type of leukocyte functions in cellular and humoral immune response?
lymphocyte
which type of leukocyte functions in phagocytosis and cellular immune response?
monocyte
___ must be present for clotting to occur
thrombocytes/platelets
in order for clotting to occur, platelet count must be >___/mm3
50,000
the goal of clotting is to minimize blood loss when injured. what is the vascular response, platelet response, and what are the plasma clotting factors involved?
- vascular response - vasoconstriction
- platelet response - activated during injury, forms clumps (agglutination)
- plasma clotting factors - I-XII, intrinsic and extrinsic pathways
what is a normal WBC blood count?
4,000-11,000 u/l
associated with infection, inflammation, tissue injury, or death
___ is the term for low WBC count
leukopenia
___ is the term for low neutrophil count
neutropenia
what is a normal RBC count for males? what about females?
- males - 4.5-5.5 x 106 u/l
- females - 4.0-5.0 x 106 u/l
___ is the percent of whole blood that is composed of red blood cells; it is a measure of both the number of red blood cells and the size of red blood cells
hematocrit
what is a normal platelet count?
150,000-400,000
___ = low platelet count
thrombocytopenia
what can happen if platelet count is below 20,000?
spontaneous hemorrhage
___ is the term for a decrease in number of RBCs, WBCs, and platelets
pancytopenia
___ is a reduction in the number of RBCs, the quantity of hemoglobin, or the volume of RBCs
anemia
anemia results in varying degrees of ___
hypoxia
because the main function of RBCs is oxygenation
what are 3 prevalent conditions of anemia?
- blood loss
- decreased production of erythrocytes
- increased destruction of erythrocytes
what are the 7 clinical manifestations of anemia?
- pallor
- fatigue, weakness
- dyspnea
- palpitations, tachycardia
- headache, dizziness, restlessness
- slowing of thought
- parasthesia
what is the etiology of hypochromic microcytic iron-deficiency anemia?
- inadequate dietary intake
- found in 30% of the world’s population
- malabsorption
- absorbed in duodenum
- GI surgery
- blood loss
- 2 ml blood contain 1mg iron
- GI, GU losses
- hemolysis
what do the cells look like in hypochromic microcytic iron-deficiency anemia?
small cells, light in color
the most common clinical manifestation of iron-deficiency anemia is ___, and the second most common is ___
- pallow
- inflammation of the tongue (glossitis)
- also common is cheilitis, sensitivity to cold, and weakness and fatigue
what are some diagnostic studies that can test for iron-deficiency anemia?
- CBC; endoscopy/colonoscopy
- iron levels: total iron-binding capacity (TIBC), serum ferritin
what is the treatment for iron-deficiency anemia?
- treatment of the underlying disease/problem
- replace iron
- oral iron - feosol, dexferrum; absorbed best in acidic environment; GI effects - constipation
- parenteral iron - IM or IV; less desirable than PO
___ is an autosomal recessive geentic disorder of inadequate production of normal hemoglobin
thalassemia
thalassemia is common in ___ groups
mediterranean ethnic
what are the clinical manifestations of thalassemia?
- asymptomatic -> major retardation -> life threatening
- splenomegaly, hepatomegaly
which thalassemia requires blood transfusions with IV deferoxamine (used to remove excess iron from the body)?
thalassemia major
which thalassemia involves the body adapting to low hemoglobin levels?
thalassemia minor
what type of anemia is characterized by large RBCs which are fragile and easily destroyed (so there are fewer)?
megaloblastic macrocytic type
what are the common forms of megaloblastic anemia?
- cobalamin deficiency (pernicious anemia)
- folic acid deficiency
- alcoholics
- pregnancy evaluation is important - neural tube defects, clefting/syndromic sysceptibility
folic acid deficiency can cause ___
megaloblastic anemia
___ is required for RBC formation and maturation
folic acid
what are some causes of folic acid deficiency?
- poor dietary intake
- malabsorption syndromes
- drugs that inhibit absorption
- alcohol abuse
- hemodialysis
in folic acid deficiency, what do the cells look like?
large and fragile
how is folic acid deficiency treated?
- folate replacement therapy
- encourage patients to eat foods with large amounts of folic acid
- leafy green vegetables, liver, mushrooms, oatmeal, peanut butter, red beans
cobalamin deficiency is a deficiency in ___
vitamin B12
___ is an important water-soluble vitamin
vitamin B12
___ is required for cobalamin absorption
intrinsic factor
what are some causes of cobalamin deficiency?
- gastric mucosa not secreting intrinsic factor
- GI surgery - loss of intrinsic factor secreting gastric mucosal cells
- long-term use of H2-histamine receptor blockers
- atrophy and loss of mucosa
- nutritional deficiency
- hereditary defects of cobalamin utilization
what are the clinical manifestations of cobalamin deficiency?
- general symptoms of anemia
- sore tongue
- anorexia
- weakness
- parasthesia of the feet and hands
- altered thought processes: confusion -> dementia
you should evaluate your patient frequently for gastric carcinoma if they have a ___ deficiency
cobalamin
a schilling test is a medical investigation used for patients with ___ deficiency, and is used to determine if the patient has ___
- cobalamin
- pernicious anemia
- intranasal form of cyanocobalamin (nascobal) is available
___ is an underproduction of RBCs and shortening of RBC survival, is the 2nd most common cause of anemia after iron deficiency anemia, and generally develops after 1-2 months of sustained disease
normochromic normocytic anemia (chronic disease)
the following are causes of which type of anemia?
impaired renal function
chronic, inflammatory, infectious or malignant disease
chronic liver disease
folic acid deficiencies
splenomegaly
hepatitis
normochromic normocytic anemia (chronic disease)
aplastic anemia is characterized by ___
pancytopenia (reduction of all blood cell types)
aplastic anemia affect ___ out of every 1 million people
4
aplastic anemia is manageable with ___ or ___
erythropoietin or blood transfusion
in what ways can aplastic anemia be a critical condition?
risk of hemorrhage and/or sepsis
what does acquired aplastic anemia result from?
exposure to ionizing radiation, chemical agents, viral and bacterial infections
anemia is caused by ___
blood loss
describe anemia caused by acute blood loss
- result of suddne hemorrhage
- trauma, surgery, vascular disruption
- replacing blood volume
- identifying source of hemorrhage
- stopping blood loss
describe anemia caused by chronic blood loss
- sources/symptoms
- similar to iron deficiency anemia
- GI bleeding, hemorrhoids, menstrual blood loss
- diagnostic studies - identify source, stop bleeding, supplemental iron administration
what are 3 types of hemolytic anemia?
- sickle cell disease
- acquired hemolytic anemia
- hemochromatosis
___ is caused by destruction or hemolysis of RBCs at a rate that exceeds production
hemolytic anemia
hemolytic anemia is the ___ major cause of anemia
third
which type of anemia (intrinsic or extrinsic) is characterized as abnormal hemoglobin, enzyme deficiencies, and RBC membrane abnormalities?
intrinsic hemolytic anemia
which type of anemia (intrinsic or extrinsic) is characterized as normal RBCs that are damaged by external factors (liver, spleen, toxins, and mechanical injury [heart valves])?
extrinsic
___ is an overproduction of red blood cells
polycythemia
what is polycythemia a result of?
- a primary process in the bone marrow (a myeloproliferative syndrome)
- or it may be a reaction to chronically low oxygen levels or malignancy
what are complications of polycythemia?
increased viscosity of blood, can lead to hemorrhage and thrombosis
what is the treatment for polycythemia?
- phlebotomy
- myelosuppressive agents
- interferon alpha-2b (intron A) therapy
- agents that target platelet number (anagrelide Iagrylin) and platelet function (aspirin)
platelet count in thrombocytopenia is <___
150,000
what are causes of thrombocytopenia?
- low production of platelets
- increased breakdown of platelets
what are symptoms of thrombocytopenia?
- bruising
- nosebleeds
- petechiae
describe immune thrombocytopenic purpura
- abnormal destruction of circulating platelets
- autoimmune disorder
- destroyed in hosts spleen by macrophages
describe thrombotic thrombocytopenic purpura
- increased agglutination of platelets that form microthrombi
what are diagnostic studies that can be performed to diagnose thrombocytopenia?
- platelet count
- prothrombin time (PT)
- activated partial thromboplastin time (aPTT)
- Hgb/Hct (hemoglobin/hematocrit)
what is the treatment for thrombocytopenia?
- based on cause
- corticosteroids
- plasmaphoresis
- splenectomy
- platelet transfusion
what is bleeding dyscrasia?
another term for bleeding abnormality
what things might you look for when determining if a patient has a history of bleeding?
- epistaxis (nose bleeds)
- easy bruising
- hematuria (bloody urine)
- heavy menstrual
- spontaneous bleeding
- medications - anticoagulants or antiplatelet agents
what would be included in the workup of a patient with a bleeding disorder?
- CBC; differential
- extrinsic vs intrinsic pathways (PT vs PTT); liver profile
- INR
- hemoglobin types: A, B, C, von willebrands disease (factor 8 c)
- are platelet problems qualitative or quantitative; numbers or other issues?
what are some local hemostatis measures can be taken with patients with bleeding disorders?
gelfoam, surgicel, thrombin/flowseal
what are the treatment options for a patient with a bleeding disorder whose INR is >3?
may need bridging with lovenox (low dose heparin); 2-3 ok to either stop coumadin or proceed with concern for hemostasis
INR will vary depending on reason for coumadin therapy
what is the protocol for treatment of patients receiving antiplatelet therapy like plavix?
anti-platelet therapy should not be stopped depending upon amount of surgery needed
ie a quadrant of extractions does not require stopping of plavix
