109 Anemia And Polycythemia Flashcards
Anemia defined
Absolute decrease in circulating RBC
RBC structure
quaternary structure w/ 4 heme polypeptide subunits
bound to an iron molecule that is contained in porphyrin rin
RBC transport of o2 depends on what 3 things?
Hemoglobin
Affinity of oxygen
Flow of blood
What does a left shift of the oxy hemoglobin cube indicate?
Higher binding affinity of o2 and poor offload of tissues
What factors may cause a left shift of the oxy hemoglobin curve to the left (ie high o2 affinity and poor offload at the tissues?)
decrease temp
decrease 2-3 dpo (genetic sometimes)
decrease H ions (ie more basic)
CO
methemoglobin
fetal hbg
What factors may cause a RIGHT shift of the oxy hemoglobin curve to the left (ie low o2 affinity and greater offload at the tissues?)
incr temp
incr 2-3 dpo
incr H –> acidosis
What hormone does anemia stimulate and what does this do?
epo regulates production of rbc and differentiation of erythroid cells to this
stimulated by tissue hypoxia and rbc destruction products
What 4 main cells does the BM stem cells make?
erythroid
myeloid
megakaryocytic
lymphoid
Erythroid cells in BM make ?
rbc
Myleoid cells in BM make ?
granulocyte - baso, neutro, eosinophil and monocytes which in turn go into macrophage
Megakaryocyte cells in BM make ?
plt
Lymphoid cells in BM make ?
t and b cells from small lymphocytes, as well as NK cells
How long do RBC last in circulation?
110-120
Reticulocytes: released every ? d, MCV of __
normal range? (%)
1-3d
mcv 60
1-3%
DDX of MCV <81 (microcytic anemia)
TAILS
thal, anemia ckd, id anemia, lead intox, sideroblastic anemia (ie aud or heavy metals poison)
DDX MCV 81-100 (normocytic anemia)
ABCD: ac bl loss, bm fail, chr dis, destruction (hemolysis)
acute blood loss
ckd
chronic disease overall
hypothyroidism
bm suppression
hemolysis
g6pd
aplastic anemia
DDX of macrocytic anemia
FAT-RBC (fetal hb, alc, thyrd, reticulocytosis-sev hemolysis, b12, cirr)
b12 defic
folate defic
liver disease
reticulocytosis
myelodyspl syndromes
etoh abuse
drugs: hydroxyurea, AZT, chemo agents
What will the findings be for iron, TIBC and ferritin in microytic anemia, with iron deficiency cause?
decr iron
incr tibc
decr ferritin
What findings of ldh and haptoglobin will hemolysis and g6pd present with?
inc ldh
decr haptoglobin
If a coombs test is +, what kind of hemolytic anemia?
autoimm
If a peripheral smear has large oval shaped rbc, hypersegmented neutrophils, think…
b12 or folat defic
If a peripheral smear has schisocytes, helmet cells spherocytes or bite cells, think…
hemolysis
g6pd
If a peripheral smear has microcytic or hypochromic rbc, think…
IDAnemia
thal
sideroblastic anemia
chronic/late disease
What is sideroblastic anemia?
inherited x linked or acquired (isonaizid, chronic etoh, lead poison) where iron accumulates in mitochondria or erythryocyte precursors and heme synthesis is impaired