Iron

Question 1

transferrin

Answer 1

protein that transports oxidized iron (Fe3+) through blood to tissues

Question 2

ferritin

Answer 2

iron (Fe2+) storage molecule within cells

Question 3

where in GI is iron primarily absorbed?

Answer 3

duodenum

Question 4

is iron ingested in oxidized or reduced form?

Answer 4

oxidized form (Fe3+). must be reduced to Fe2+ via Reductase enzyme on intestinal epithelium before absorption

Question 5

transport protein for iron into intestinal epithelia?

Answer 5

DMT1 (reduced form Fe2+)

Question 6

transport protein for iron out of intestinal epithelial into blood stream

Answer 6

Ferroportin (FPN1). transports (Fe2+), oxidase enzyme oxidizes the molecule to Fe3+ before it is bound to transferrin

Question 7

where does process of iron recycling begin?

Answer 7

within macrophages

Question 8

major source of iron for erythropoeisis

Answer 8

recycling

Question 9

iron exporter out of macrophages?

Answer 9

ferroportin

Question 10

iron regulatory hormone produced in liver

Answer 10

hepcidin

Question 11

what type of regulator is hepcidin?

Answer 11

negative regulator

Question 12

functions of hepcidin

Answer 12

inhibits intestinal iron absorption and macrophage release of iron

Question 13

stimuli that decrease hepcidin levels

Answer 13

iron deficiency, increased erythroid demand, hypoxia (all times when we need more iron)

Question 14

stimuli that increase hepcidin levels

Answer 14

iron overload, inflammation

Question 15

mechanism of hepcidin

Answer 15

binds to and down regulates ferroportin, thereby inhibiting iron release from macrophages or intestinal epithelia

Question 16

causes of iron deficiency

Answer 16

inadequate supply (nutritional & malabsorption) or increased demand (blood loss, rapid growth, pregnancy)

Question 17

what can help increase the absorption of iron?

Answer 17

eating heme iron from meat and intake of vitamin C (enhances absorption somehow)

Question 18

signs & symptoms of iron deficiency

Answer 18

pallor, weakness, fatigue, headache, irritability, pica, koionychia, angular stomatitis, blue sclerae

Question 19

koilonychia

Answer 19

spoon finger nails

Question 20

angular stomatitis

Answer 20

inflammation of corner of lips

Question 21

hematologic markers of iron deficiency

Answer 21

decreased Hb, RBC, MCV, reticulocyte count

increased RDW, platelets

Question 22

biochemical markers of iron deficiency

Answer 22

decreased ferritin, serum Fe, transferrin saturation

increased TIBC, FEP

Question 23

TIBC

Answer 23

total iron binding capacity. increased values indicate greater number of open iron binding sites on transferrin

Question 24

treatment for iron deficiency

Answer 24

correct the deficiency via oral ferrous sulfate/slow release iron/parenteral iron/red cell transfusion. then correct the underlying cause

Question 25

characteristics of anemia from chronic inflammation

Answer 25

mild/moderate anemia, normo/microcytic, normal/low reticulocytes. decreased serum Fe, normal iron stores, increased serum ferritin (weird mix of iron deficient and replete symptoms)

Question 26

general characteristic of anemia from chronic inflammation

Answer 26

abnormal systemic iron distribution.

Question 27

what is most likely cause of anemia from chronic inflammation

Answer 27

hepcidin excess due to inflammatory cytokine stimulation

Question 28

best test to distinguish iron deficiency anemia from anemia of chronic inflammation?

Answer 28

serum ferritin levels (high in ACI, low in IDA)