iron deficiency anaemia W8

Question 1

anaemia definition?

Answer 1

serum haemoglobin levels are 2 standard deviations below the normal

Question 2

iron deficiency definition?

Answer 2

total body iron is low as a result of absorption not matching demand

Question 3

IDA epidemiology?

Answer 3

iron deficiency anaemia in 2-5% adult males and non-menstruating females
10% of these with have underlying malignancy
if iron deficient but not anaemic, around 1% will have an underlying malignancy

Question 4

causes of IDA?

Answer 4

poor intake of dietary iron
reduced absorption (malabsorption) eg coeliac, post surgery
increased iron (blood) loss eg menstruation, cancer
increased demand eg pregnancy, adolescence

Question 5

IDA symptoms?

Answer 5

often none

common symptoms - tiredness, dyspnoea, headache

common signs - pallor, atrophic glossitis

rarer signs - koilonychia, leukonychia, tachycardia, angular cheilosis

Question 6

iron absorption?

Answer 6

2 forms:
Fe2+ = haem iron (found in red meat, sea food. readily absorbed by the body.)
Fe3+ = non-haem iron (less absorbable, needs to be converted to Fe2+.)

Question 7

iron absorption - enhancers?

Answer 7

vit C
fructose
sorbitol
alcohol

Question 8

iron absorption - inhibitors?

Answer 8

tannins
oxalates
polyphenols
phytates
egg, pulse proteins
calcium
copper
manganese

Question 9

what part of the body is iron used in? what is it essential for?

Answer 9

muscle, liver, bone marrow, spleen
essential for enzymes

Question 10

enterocyte iron absorption

Answer 10

Fe3+ harder to absorb than Fe2+
body stores iron within cells as ferritin, this is what is measured for total body iron stores.

Question 11

main condition IDA is confused with?

Answer 11

anaemia of chronic disease

Question 12

mechanism of anaemia of chronic disease (AoCD)?

Answer 12

caused by ongoing inflammation.
-increases hepatic synthesis of hepcidin (inhibits release of iron from RES)
-inhibits erythropoietin release
-inhibits erythroid proliferation
-augments hemophagocytosis

Question 13

what is a marker of total body iron stores?

Answer 13

ferritin (not serum iron)

Question 14

how to tell the difference between iron deficiency anaemia and AoCD?

Answer 14

low ferritin = IDA
transferrin high = IDA
transferrin normal/low = AoCD

Question 15

explanation of transferrin levels?

Answer 15

body’s iron is low, therefore more transferrin is made to move more iron

body has full iron stores (eg in AoCD), transferrin levels normal/low as don’t need to move iron around the body

Question 16

iron deficiency anaemia defined as?

Answer 16

low haemoglobin in the presence of either
-low ferritin (best diagnostic marker)
-low serum iron in the presence of transferrin >3.0

Question 17

what can iron deficiency anaemia be caused by

Answer 17

loss of iron (menstrual, GI, renal)
malabsorption (previous gastric surgery, coeliac disease)
poor dietary iron intake (poor diet, lifestyle choices, cultural beliefs)

Question 18

what test should everyone get in IDA?

Answer 18

coeliac disease (anti tTG antibodies)

Question 19

commonest cause of IDA?

Answer 19

menstrual blood loss

Question 20

transnasal endoscopy positives/negatives?

Answer 20

positive -
better tolerated
usually only under local anaesthetic
biopsy standard equivalency
endoscopy only test able to adequately visualise the stomach

negative -
unable to perform most therapeutic procedures

Question 21

standard colonoscopy positives?

Answer 21

remains gold standard
able to take biopsies and perform polypectomy

Question 22

standard colonoscopy negatives?

Answer 22

invasive
can be uncomfortable
need to take prep
can miss lesions
possibilities of complications - bleeding/perforation

Question 23

CT colonoscopy positives?

Answer 23

mostly non-invasive
min prep for frail patients
fast
less risks
effective as colonoscopy for polyps >5mm

Question 24

CT colonoscopy negatives?

Answer 24

still need to take prep
radiation dose
if shows lesion will still need colonoscopy
can result in incidentalomas

Question 25

capsule endoscopy shows what area of the bowel?

Answer 25

small intestine

Question 26

treatment of IDA?

Answer 26

optimise diet
oral iron supplementation for 3 months after iron deficiency corrected
main side effects are constipation, GI upset, dark stools

if unable to tolerate then some evidence to suggest once daily dosing/alternate day dosing is effective

if unable to tolerate that then IV iron