Microcytic Anemia

Question 1

reasons for microcytosis

Answer 1

decreased globin production
decreased heme productio
reduced Fe availabilty

Question 2

2 reasons for reduced globin producton

Answer 2

thalassemia

hemoglobinopathies

Question 3

2 reasons for reduced heme synthesis

Answer 3

lead poisioning

sideroblastic anemias

Question 4

2 reasons for reduced Fe availability

Answer 4

absolute Fe deficiency

functional Fe deficency (chronic illness/inflammation

Question 5

prevalence of Fe from most to least

Answer 5

hemoglobin
ferritin in MO, spleen, bone marrow, liver
myoglobin
bound to transferrin (in plasma)

Question 6

iron excretion

Answer 6

no physiologcial way exept 1-2 mg/day lost through desquamation (shedding skin)

Question 7

hepcidin

Answer 7

how Fe absorption is regulated at level of duodenum

Question 8

heme

Answer 8

iron complexed to protoporphyn IX

Question 9

enhances Fe absorption

Answer 9

ascorbic acid

Question 10

reduced Fe absorption

Answer 10

Ca, antacids, phyates (in brans and oats), polyphenols (in tea and some veggies)

Question 11

TS

Answer 11

how much of the transferrin is bound to Fe
decrease= decreased Fe
increase= iron overload

Question 12

best test to show if Fe deficiency is present

Answer 12

ferritin

Question 13

ferritin can be elevated by

Answer 13

inflammation

Question 14

causes of Fe deficiency

Answer 14

inadequate oral intake
inadequate absorption (messed up duodenum)
increased loss (bleeding)
intravascular hemolysis
depletion of epo

Question 15

clinical signs Fe deficiency

Answer 15

pica
restless leg syndrome
plummer-vinson syndrome

Question 16

thalaseemias

Answer 16

autosomal recessive quantitative disorder with insufficient production of alpha and beta-globin chains

Question 17

normal adults hb types

Answer 17

95-98% HgbA1 (a2b2)
2-3% HgbA2 (a2d2)
1-2% HgbF (a2,g2)

Question 18

where does B thalasemia occur?

Answer 18

SE asia (burma, thailand, cambodia, vietname, china, malaysia, indonesia, phillipines)

Question 19

B thalasemia produces no

Answer 19

HbA1- agg of alpha chans therefore decrease in RBC lifespan

Question 20

compensatory mech of B thala

Answer 20

increase in fetal Hb

Question 21

alpha thal found in

Answer 21

se asia
africa
india

Question 22

what happens in a thal

Answer 22

impaired production of alpha globin chans wth resultant excess beta globin chains that are toxc to RBC membrane skeleton

Question 23

treatment thal a

Answer 23

does not require much; sometmes splenectomy

genetc counseling can be helpful to reduce rsk of H dsease and hydrops fetalis

Question 24

comp mech of thal a

Answer 24

relative excess of other chains

Question 25

diagnoss thal a

Answer 25

dna analysis

Question 26

sideroblastic anemia

Answer 26

decrease in heme synthesis; erythroblasts accumulate Fe in mitochondra without being able to produce adequate heme

Question 27

primary sideroblastic disease

Answer 27

myelodysplasia with ringed sideroblasts

Question 28

secondary sideroblastic disease

Answer 28

nutritional: B6 or Cu deficiency
Drugs- isoniazid, chloramphenicol, phenacetin, alkylating agents
alcohol
toxins: lead, zinc poisioning

Question 29

labs sideroblasts

Answer 29

serum Fe- INC
ferritin- INC
Transferrin (total Fe)- normal/dec
TS- INC

Question 30

treatment sideroblastic anemia

Answer 30

figure out cause
try pyrdoxine or folic acid
iron chelators/PRBC transfusions`

Question 31

neurological findings with lead poisioning

Answer 31

motor neuropathy
autonomic neuropathy–> abdominal pain and lead colic
insomnia, irritability, psychosisw

Question 32

what does lead do to your body

Answer 32

inhibits both heme and globin synthesis, interefers with RNA breakdown which causes accumulaton of denatured RNA in blood cells–> basophlic stippling

Question 33

treatment lead poisioning

Answer 33

chelators

remove agent