RBC's Flashcards
three broad categories of anemias
- blood loss
- decreased RBC survival
- decreased RBC production
example of blood loss anemia
hemorrhage
trama
example of decreased RBC survival
hereditary spherocytosis
mechanical trauma
transfusion reactions
example of decreased RBC production
B12 deficiency
iron deficiency
folate deficiency
aplastic anemia
RBC can be intravascular hemolysis or extravascualr
intravascular- in the circulation
extravascular- reticuloendothelial system including spleen
reticuloendothelial system
The cells are primarily monocytes and macrophages, and they accumulate in lymph nodes and the spleen.
example of intravascular hemolysis
mechanical trauma
key feature of intravascular hemolysis
decrease haptoglobin, low levels
example of extravascular hemolysis
hereditary sperhocytosis, sickle cell anemia, erythroblastosis fetalis
what happens in extravascular hemolysis
damaged or abnormal RBC are removed in spleen, hemoglobin is broken down. hemo breakdown products increase (hyperbilirubinemia).
high levels of bilirubin can cause what
gallstones
intrinsic defects
inherited
4 examples of intrinsic defects
membrade defects- hereditary spherocytosis
abnormal hemoglobin- sickle cell anemia
lack of globin chain- thalassemia
metabolic- G6PD deficiency
Hereditary spherocytosis
quan or qual defect in spectrin, a structural protein of cytoskeleton leads to prodution of spherocytes
spherocytes
smaller more dense RBC’s
why are spherocytes bad?
- cant flex as much to get into smaller capillaries
- more prone to rupture
- destroyed by spleen
inheritance pattern of hereditary spherocytosis
auto Dominant
what operation do people usually get with this disease
removing spleen, destruction of spherocytes is decreased
example of disease that produces abnormal hemoglobin
sickle cell anemia- auto codominant
sickle shape RBC bad because…
they get destoryed by spleen (extravascular)
clog up smaller capillaries
carriers of sickle cell disease have an increase resistance to what
malaria
what is thalassemia
inherited disorder. diminished or absent synthesis of either the alpha or beta globin chains of hemoglobin. decreased production of hemo and hemo gets destroyed more by spleen (extravascular)
decreased globin chain synthesis means decreased…
hemoglobin production
principal clinical manifestation of thalassemia
anemia
this is more common in persons of mediterranean, african, southeast asian descent
thalassemia
intrinsic metabolic defect
G6PD deficiency
what is G6PD deficiency
X linked inheritance. cells are susceptible to oxidant injury by drugs or toxins
examples of extrinsic defects and whether they are intra or extravascular hemolysis
erythroblastosis fetalis- extravasuclar
hemolytic transfusions- intravascular
mechanical trauma- RBCs going through abnormal vavles
important antigens in erythroblastosis fetalis
ABO and Rh antigens
characterized by incrased amount of schistocytes
mechanical trauma- cardiac valve prosthesis
most common cause of anemia worldwide
iron deficiency
what kind of anemia is result of low iron
microcytic anemia- smaller RBC’s containing less hemoglobin
low iron causes…
- inadequate intake (infants)
2. increased requirement- puberty, pregnancy, elderly
diagnosis of microcytic anemia by
lab test
megaloblastic anemia
vit B12 and folate deficiency- leads to impaired DNA synthesis, resulting in large red cell precursor (megaloblast)
what do you need for B12 absorption
intrinsic factor
what is pernicious anemia
when pt’s have autoantibodies against intrinsic factor so they cant absorb vit B12
aplastic anemia
decreased production of all cellular elements in blood, no predisposing cause. drugs and viral infection can cause it
STEM CELL ABNORMALITY
what is myelophthisic anemia
when normal hematopoietic cells in marrow are crowded out by tumor or fibrosis
cyanotic heart disease, living at high altitude, pulmonary disease, abnormal hemoglibin all cause what kind of polycythemia
secondary
what is secondary polycythemia
disease or environmental factors stimulate erythropoietin, increases growth of RBC
what is primary polycythemia
RBC proliferate on their own, non regulated, called polycythemia vera
polycythemia vera can cause what
neurologic and visual abnormalities
treatment of polycythemia vera
phlebotomy
what distinguishes primary from secondary
erythropoietin levels, secondary have increased levels
