Iron

Question 1

where is iron bound to porphyrin ring

Answer 1

mitochondria

Question 2

what state is iron found in in mitochondria

Answer 2

Fe3+

Question 3

where is iron mostly stored

Answer 3

in Hb

Question 4

other places iron is found

Answer 4

plasma
erythroid marrow
macrophages
liver stores

Question 5

where is iron abdorbed from

Answer 5

duodenum

Question 6

through what transporter does iron enter enterocyte

Answer 6

DMT1

Question 7

how is iron transported out of enterocyte

Answer 7

ferroportin

Question 8

what picks up iron in blood

Answer 8

transferrin

Question 9

what can affect expression of ferroportin

Answer 9

hepcidin - decreases expression of ferroportin

traps iron in enterocytes and macrophages

Question 10

when is hepcidin produced

Answer 10

protein produced with increased iron load and in inflammation

Question 11

what form is it easier to absorb iron in

Answer 11

ferrous Fe2+

Question 12

what does ferritin act as

Answer 12

acute phase protein (increased in infection, malignancy, inflammation etc

Question 13

why do people with chronic diseases become anaemic

Answer 13

increased ferritin as response to acute inflammation
hepcidin released in response
prevents iron binding to transferrin
less iron to marrow causing hypochromic red cells

Question 14

measurement of functional iron

Answer 14

Hb conc

Question 15

measurement of transport iron/iron supply to tissues

Answer 15

%transferrin saturation (normal is 20-50%)

Question 16

measurement of storage iron

Answer 16

serum ferritin (requires tissue biopsy)

Question 17

what kind of iron is transported by transferrin

Answer 17

Fe3+

Question 18

what is holotransferrin

Answer 18

transferrin + iron

Question 19

what is apotransferrin

Answer 19

unbound transferrin

Question 20

epithelial changes of iron deficiency

Answer 20

koilonychia

angular stomatitis

Question 21

what kind of anaemia does iron deficiency cause

Answer 21

microcytuc

Question 22

causes of iron deficiency

Answer 22

insufficient diet
bleeding (menorrhagia, tumours, ulcers, NSAIDs)
malabsorption

Question 23

how much blood loss can occur per day with no symptoms

Answer 23

8-10 ml

Question 24

gene mutated in haemochromatosis

Answer 24

HFE

Question 25

pathophysiology of haemochromatosis

Answer 25

decreased hepcidin production

increased unopposed iron absorption

Question 26

clinical manifestations of haemochromatosis

Answer 26

weakness/fatigue
joint pain 
impotence
arthritis
cirrhosis 
diabetes
cardiomyopathy

Question 27

penetrance of haemochromatosis

Answer 27

incomplete

Question 28

management of haemochromatosis

Answer 28

weekly venesection (exhaust iron stores)

Question 29

what are secondary causes of iron overloading

Answer 29

repeated cell transfusions
ineffective erythropoiesis (thalassaemia, sideroblastic anaemia)
hypoplasic anaemia

Question 30

treatment of secondary iron overload

Answer 30

iron chelating agents -
desferrioxamine
deferiprone
deferasirox