Term
| most common iron assessment tools |
|
Definition
| hemoglobin and hematocrit |
|
|
Term
| first stage of iron deficiency |
|
Definition
| iron stores in liver, spleen, and bone marrow are diminished |
|
|
Term
| first stage iron def. assessments |
|
Definition
| 1)measure bone marrow plasma ferritin (<12mcg/L def), not a good indicator cuz depedent on other factors; better is iron content of ferritin, or % saturation of iron |
|
|
Term
|
Definition
-stores remain low and transport of iron, decreases
-circulating iron decreases
-transferrin sat decreases to <16%
-[serum iron] decreases to <50 mcg/dL |
|
|
Term
|
Definition
[serum iron] x 100/ TIBC
where TIBC = total iron binding capacity, normally it's 250-400 mcg/dL, levels >400 def. |
|
|
Term
|
Definition
-cellular iron becomes limiting
-free [pprotporphyrin] in erythrocytes rise
-proto >70mcg/dL RBS def.
-# of transferrin receptors on cells increase
-serum transferrin receptors increase to >8.5 mg/L |
|
|
Term
|
Definition
-anemia occurs
-hemoglobin and hematocrit decrease
-[hemoglobin] <12g/dL and 13g/dL
-[hematocrit] <37 and <40% |
|
|
Term
|
Definition
-mean corpuscular volume
-size of RBCs
=(hematocrit/RBC #) x 100 |
|
|
Term
|
Definition
-mean corpuscular hemoglobin []
-avg hemoglobin content of each RBC
= (hemoglobin/hematocrit) x 10 |
|
|
Term
|
Definition
-mean corpusculare hemoglobin []
-amount of hemoglobin in g/dL of RBC
=(hemoglobin/hematocrit) x 100 |
|
|
Term
|
Definition
| hypochromic and microcytic |
|
|
Term
|
Definition
| -genetic disorder characterized by increases (at least 2x normal) iron absorption; body can't accurately assess iron stores; absorbed iron deposited in liver, heart and pancrease, causing organ damage |
|
|
Term
| hemochromatosis treatment |
|
Definition
| usually involves frequent phlebotomy (blood letting) and may require administration of deferroxamine (kelating agent) |
|
|
Term
| Ppl at risk for iron toxicity |
|
Definition
| those with iron-loading anemia, thalassemia, and sideroblastic anemia |
|
|
Term
|
Definition
| ascorbic acid enhances absorption |
|
|
Term
|
Definition
| role of copper containing ceruloplasmin is a ferroxidase, and it's needed to mobilize iron from ferritin stores |
|
|
Term
|
Definition
| only affected with supplement intake (not seen from just food ingestion), 25:1 of nonheme (ferrous sulfate): zinc diminished absorption of zinc from H2O by 34% |
|
|
Term
|
Definition
| decreasing A status alters iron distribution among tissues, low plasma [retinol] are associated with decreased plasma iron and blood hemoglobin and hematocrit as well as increased hepatic iron accumulation |
|
|
Term
|
Definition
| lead inhibits activity of zinc-dependent aminolevulinic acid dehydratase required in heme synthesis; lead also inhibits ferrochelatase which incorporates iron into heme |
|
|
Term
|
Definition
| iron def. is associated with decreased selenium -> glutathione peroxidase requires selenium and catalyzes reduction of H2O2 to H2O |
|
|
Term
| Why does body need to conserve iron? |
|
Definition
| Because we don't absorb enough from diet |
|
|
Term
| How is hemoglobin degraded? |
|
Definition
| primarily by phagocytes of reticuloendothelial system (in liver, spleen, and bone marrow) |
|
|
Term
|
Definition
| About 120 days; old are taken up by macrophages in spleen and degraded; reticuloendotheilial cell macrophages in bone marrow and Kupffer cells in liver |
|
|
Term
|
Definition
1) heme catabolized by heme oxygenase to biliverdin and bilirubin
2) biliverdin and bilirubin excreted into bile for excretion in feces |
|
|
Term
| Hemoglobin degradation leads to how much iron release? |
|
Definition
|
|
Term
| Iron degradation that occurs within blood |
|
Definition
| haptoglobin and hemopexin remove and release hemoglobin and any free heme from blood, then liver does further degradation |
|
|
Term
| Significant hemolysis and erythropoesis decrease has what effect on iron? |
|
Definition
1) hemolysis - iron quantity passing thru plasma can expand 6-8 x
2) decreased erythropoeisis - iron in plasma pool may decrease to as little as 1/3 of normal (ie in high altitudes) |
|
|
