268b Fe deficient anemia

Question 1

where is iron absorbed in intestine?

Answer 1

duodenum

“Iron Fist, Bro” = iron (duodenum), folate (jejunum, ileum), B12 (terminal ileum)

Question 2

hepcidin - fxn? decreased by? increased by?

Answer 2

degrades ferroportin, prevents ferritin from releasing iron –> can’t transport iron –> low iron, TIBC; high ferritin

decreased by: hypoxia, increased erythroid activity, Fe deficiency

increased by: inflammation (to keep bugs from getting iron), Fe sufficiency

Question 3

ferroportin

Answer 3

iron transporters in macrophages, enterocytes, hepatocytes

Question 4

what does low hepcidin result in? high?

Answer 4

hemochromatosis - iron overload

IRIDA - iron deficiency

Question 5

transferrin - fxn?

Answer 5

binds circulating Fe

takes Fe to bone marrow erythroblasts for hemoblogin (via transferrin receptor – upregulated in iron deficiency anemia)

Question 6

how is iron measured - serum ion? TIBC? ferritin?

Answer 6

serum iron - Fe bound to transferrin

total iron binding capacity - how much Fe can bind to transferrin

ferritin - measure of total body iron stores

Question 7

Fe deficient anemia -overview?

Answer 7

low iron due to chronic bleeding (GI loss, menorrhagia), malnutrition/absorption (duodenum) disorders or high demand (e.g., pregnancy) –> decreased final step in heme synthesis.

Question 8

Fe deficient anemia- serum iron findings? symptoms? RBC appearance?

Answer 8

low iron, high TIBC, low ferritin.

Fatigue, conjunctival pallor

Microcytosis and hypochromia

**can lead to Plummer-vinson syndrome (Fe def anemia, esophageal webs, atrophic glossitis)

Question 9

anemia of chronic disease/inflammation - overview

Answer 9

Inflammation (IL-6) –> increased hepcidin (released by liver, binds ferroportin on intestinal mucosal cells and macrophages, thus inhibiting iron transport) –> decreased release of iron from macrophages.

Question 10

anemia of chronic disease/inflammation - serum findings?

Answer 10

low iron, low TIBC, high ferritin.

usually normochromic and normocytic but can become microcytic, hypochromic if severe

Question 11

what iron study difference is there between anemia of inflammation and Fe deficient anemia?

Answer 11

both have reduced Fe and Fe saturation

anemia of inflammation - increased ferritin (acute phase reactant that stores Fe), EPO not high enough

Fe deficient anemia - reduced, EPO high

Question 12

hemochromatosis - overview? causes? genetics?

Answer 12

Hemosiderosis is the deposition of hemosiderin (iron); hemochromatosis is the disease caused by this iron deposition

Disease may be 1° (autosomal recessive) –> low hepcidin or 2° to chronic transfusion therapy (e.g., B-thalassemia major).

Primary hemochromatosis due to C282Y or H63D mutation on HFE gene. Associated with HLA-A3.

Question 13

hemochromatosis - serum findings

Answer 13

^ ferritin, ^ iron, low TIBC–> high transferrin saturation.

Question 14

hemochromatosis - persentation

Answer 14

Classic triad of micronodular Cirrhosis, Diabetes mellitus, and skin pigmentation –> “bronze” diabetes.

Results in CHF, testicular atrophy, and ^ risk of HCC

“hemochromatosis Can Cause Deposits (CCD)”

Question 15

Hemochromatosis - Rx?

Answer 15

repeated phlebotomy

deferasirox, deferoxamine.