Hematology Flashcards
red blood cells
transports O2 and CO2
develops in bone marrow
120 day lifespan
white blood cells
immune defense
platelets
clot formation and prevention
albumins
osmolarity and viscosity
globulins
transport - transferrin transports iron in blood
storage - iron is stored in the liver as ferritin
hematopoiesis
blood cell production
undifferentiated hematopoietic stem cells
give rise to all other different types of specialized blood elements
progenitor cells
descents of stem cells that further differentiate to create specialized cells
lymphoid cells
myeloid cells
growth inducers
controls growth an reproduction
IL3 growth inducer for all committed stem cells
induced by low O2 exposure
differentiation inducers
causes one type of committed stem cell to differentiate one or more steps towards a final adult blood cell
induced by low O2 exposure
erythropoietin (EPO)
stimulates RBC production
released by the kidneys
thrombopoiesis
platelet production
thrombopoietin
stimulates platelet production
produced in kidneys and liver
leukopoiesis
leukocyte production
lymphoid cells
migrate from bone marrow to lymphatic tissue for differentiation
lymph nodes
spleen
thymus
erythropoiesis
RBC production
why do males have a higher RBC count/hematocrit compared to women?
testosterone stimulates EPO release by the kidney which stimulates RBC production
heme groups
make by reusing iron
heme converted to bilirubin which is incorporated in bile and excreted
folic acid
needed for formation of DNA which is essential for cell division
vitamin B12
essential for DNA which is needed for production, proliferation, and maturation of RBCs
iron
component of hemoglobin
hypoxia-inducible factor-1 (HIF-1)
increases due to renal tissue hypoxia
serves as a transcription factor for EPO gene to increase EPO synthesis
non-renal sensors
norepinephrine, epinephrine, and other prostaglandins send signals to the the kidneys to produce EPO
hematocrit (Hct)
percentage of RBCs in total blood volume
depends on gender and environment
increased EPO = increased Hct
haemoglobin
globular protein that is the primary vehicle for transporting O2 in RBCs
heme + polypeptide (2alpha + 2beta chains) = hemoglobin
globin chain synthesis
occurs in the cytosol of RBCs by transcription and translation
heme synthesis
occurs in cytosol and mitochondria of RBCs
glycine + succinyl coenzyme A = protoporphyrin ring
protoporphyrin ring binds to iron ions to form heme
anemia
below normal O2 carrying capacity of blood
low hemoglobin and hematocrit
mean corpuscular hemoglobin (MCH)
average quantity of hemoglobin present in a single RBC
MCH = [Hb]/RBC
normochromic = 27-31pg
hypochromic = <25pg
hyperchromic = >50pg
mean corpuscular hemoglobin concentration (MCHC)
measure of concentration of hemoglobin in a given volume of package RBCs
MCHC = [Hb]/Hct
normochromic = 31-37%
hypochromic = <31%
spherocytosis = >37%
central decrease rate of RBCs
inside bone marrow
erythropoietic tissue destroyed
exposure to chemicals e.g. Benzene
toxicity of chemotherapies
invasion of bone marrow by cancer e.g. Leukemia
aplastic anemia
aplastic anemia
due to bone marrow aplasia, autoimmune disorders, benzene toxicity and decreased Hb
peripheral decrease rate of RBCs
outside bone marrow
low EPO and insufficient vitamin B12 (cyanocobalamin)
pernicious anemia
megaloblastic anemia
pernicious anemia
vitamin B12 deficiency
abnormal and diminished DNA
produces macrocytes - large, oval, flimsy
can carry O2 but fragile
antibodies against intrinsic factor in GIT
atrophic gastritis
conditions affecting small intestine
smooth thick red tongue
enlarged liver
megaloblastic anemia
folic acid/folate deficiency
sprue/celiac disease causes difficulty absorbing folic acid and B12 producing macrocytes and impairing DNA synthesis
knuckles and terminal phalanges hyperpigmentation
enlarged liver and spleen
signs and symptoms of folate/B12 deficiency
anemia - low Hct and Hb
macrocytes
fragile erythrocytes - yellowish skin and mucosa
iron deficiency
lack of iron intake
chronic diseases
excess blood loss - chronic bleeding in intestines (ulcers or cancer) and heavy menses
fatigue and dark stool
hemorrhagic anemia
result of acute or chronic blood loss
acute blood loss
low O2 carrying capacity - hyper stimulated bone marrow
increased reticulocytes in blood
chronic blood loss
2-3 months - high bone marrow activity
more than 3 months - decreased bone marrow activity
decreased iron absorption (Hb rapidly lost)
iron stored depleted
no reticulocytes in blood
hemolytic anemia
excessive blood cell destruction
autoimmune
infection of RBCs - malaria
fragile cells
hypersplenism
hereditary spherocytosis
