Term
|
Definition
| lack of iron due to decreased intake or decreased absorption or increased loss of iron. Usually associated with Iron deficiency anemia and heme synthesis disorders |
|
|
Term
|
Definition
| defect in iron utilization due to block of iron insertion into protoporphyrin ring, associated with Sideroblastic Anemia (defective porphyrin) and Anemia of Chronic Disease (defective reuse of iron), a heme synthesis disorder |
|
|
Term
|
Definition
| plasma β1-globulin responsible for binding iron and its transport in the bloodstream. Each gram of transferrin can bind 1.25mg of iron. The capacity of transferrin to bind iron is functionally measured as the total iron-binding capacity (TIBC). Transports iron in the ferric form, after transport transferrin is recycled. Bone marrow has highest levels of transferrin receptors, so most iron is delivered there. Transferrin is a negative acute-phase reactant produced by the liver, and increases in pregnancy. |
|
|
Term
|
Definition
|
|
Term
| Percentage of normally saturated Transferrin |
|
Definition
|
|
Term
|
Definition
| water insoluble, heterogeneous iron-protein complex found primarily in the cytoplasm of cells (normoblasts and histocytes in the bone marrow, liver, and spleen); the major long-term storage form of iron. It is readily visible microscopically in unstained tissue specimens as irregular aggregates of golden yellow to brown granules. It may be visualized with Prussian-blue stain as blue granules. The granules are normally distributed randomly or diffuse. Iron/protein aggregate that is 50% iron and usually present at higher iron concentrations. Used for long term storage and slow release of iron |
|
|
Term
| Percentage of sideroblasts in bone marrow |
|
Definition
|
|
Term
|
Definition
| iron-phosphorus-protein compound formed when iron complexes with the protein apoferritin. It is a storage form of iron found primarily in the bone marrow, spleen, and liver. Small amounts can be found in the peripheral blood proportional to that found in the bone marrow. Primary intracellular storage form of iron, and readily released for heme synthesis. |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Total iron binding capacity: refers to the total amount of iron that transferrin can carry |
|
|
Term
| 3 physiologic factors that affect the amount of iron needed by the body |
|
Definition
| menstruation, pregnancy, and growth |
|
|
Term
| How does menstruation affect iron levels? |
|
Definition
| average daily iron loss is menstruating females is twice that if their male counterparts, to maintain total body iron balance, menstruating females must absorb 2 mg of iron daily |
|
|
Term
| How does pregnancy affect iron levels? |
|
Definition
| : daily iron requirement during pregnancy is 3.4 mg because the fetus accumulates most of the iron from maternal stores via the placenta |
|
|
Term
| How does growth affect iron levels? |
|
Definition
| growth of body and size and hemoglobin mass requires more iron in proportion to food intake |
|
|
Term
| 4 pathologic conditions that increase the need for iron? |
|
Definition
| blood loss, malabsorption, and human recombinant erythropoietin therapy in hemodialysis patients with anemia |
|
|
Term
| Peripheral Blood findings in IDA? |
|
Definition
| microcytic (MCV 55-74fl) and hypochromic (MCHC 22-31 g/dL), MCH (14-26 pg), relative and absolute reticulocyte counts can be normal or slightly increased |
|
|
Term
| Iron Studies seen in IDA? |
|
Definition
|
|
Term
| Peripheral blood findings in ACD? |
|
Definition
| increased myeloid: erythroid ration, few erythroid precursors seen |
|
|
Term
| Iron studies seen in ACD? |
|
Definition
| decreased serum iron, normal iron stores due to defective recycling of iron |
|
|
Term
| Anemia of Chronic Disease (definition) |
|
Definition
| anemia that occurs in patients with chronic infections, chronic inflammatory disorders, trauma, organ failure, or neoplastic disorders |
|
|
Term
| Lead posioning (definition) |
|
Definition
| inhibits enzymes of heme synthesis |
|
|
Term
| Peripheral blood findings in lead posioning? |
|
Definition
| microcytic hypochromia anemia, basophilic stippling |
|
|
Term
| Iron studies seen in lead posioning? |
|
Definition
| iron is not incorporated into the protoporphyrin ring, urine excretion of delta- ALA increases, ZPP is increased, iron accumulated in the cell |
|
|
Term
| Sideroblastic anemia (definition) |
|
Definition
| mutation that affect the first enzymatic step in heme synthesis, the formation of ALA |
|
|
Term
| Peripheral blood findings in sideroblastic anemia? |
|
Definition
| duel population of hypochromic and normochromic erythrocytes, Pappenheimer bodies |
|
|
Term
| Iron studies seen in sideroblastic anemia? |
|
Definition
| increased serum iron, serum ferritin, and percent saturation |
|
|
Term
| Iron deficiency Anemia Etiology |
|
Definition
| due to (1) dietary deficiency (2) blood loss (3) kidney disease or (4) malabsorption |
|
|
Term
| Iron deficiency Anemia pathophysiology |
|
Definition
Stage 1- Iron depletion: Iron stores exhausted, decreased ferritin, no anemia or abnormal RBC morphology, increased RDW
Stage 2- Iron deficient Erythropoiesis: insufficient iron to insert into protoporphyrin ring to form heme. Increased Zinc protoporphyrin, no anemia or hypochromia, slight microcytosis, reticulocyte Hgb < 26 pg
Stage 3- Iron deficiency Anemia: microcytic hypochromia, all iron studies are normal |
|
|
Term
| Anemia of Chronic Disease etiology |
|
Definition
| block in mobilization of iron, unable to recycle iron to bone marrow normoblasts, the block is mediated by increase in hepcidin in response to inflammatory cytokines |
|
|
Term
| Anemia of Chronic Disease Pathophysiology |
|
Definition
| normochromic/normocytic to hypochromic/microcytic, decreased reticulocyte count, increased myeloid: erythroid ratio in bone marrow due to decreased RBC precursors |
|
|
Term
| Sideroblastic Anemia Etiology |
|
Definition
| can be hereditary or acquired. Hereditary sideroblastic anemia is sex-linked and Autosomal recessive. Acquired sideroblastic anemia can be due to unknown factors or secondary to disease or toxin. |
|
|
Term
| Sideroblastic Anemia pathophysiology |
|
Definition
| anemia due to disturbances of the enzymes regulating heme synthesis. Ringed sideroblasts are formed from an accumulation of nonferritin iron in the mitochondria that encircle the erythroblasts nucleus. |
|
|
Term
| Transferrin saturation % (calculation) |
|
Definition
|
|
Term
|
Definition
|
|
Term
| The three stages of iron deficiency |
|
Definition
Stage 1- Iron depletion
Stage 2- Iron deficient Erythropoiesis
Stage 3- Iron deficiency anemia |
|
|
Term
| RBC morphology at stage 1 of iron deficiency anemia |
|
Definition
| No anemia or abnormal RBC morphology |
|
|
Term
| RBC morphology at stage 2 of iron deficiency anemia |
|
Definition
| slight microcytosis, reticulocyte Hgb > 26 pg |
|
|
Term
| RBC morphology at stage 3 of iron deficiency anemia |
|
Definition
|
|
Term
| Iron studies at stage 1 of IDA |
|
Definition
| iron stores are exhausted indicated by decreased serum ferritin. No anemia or abnormal RBC morphology. Increased RDW |
|
|
Term
| Iron studies at stage 2 of IDA |
|
Definition
| insufficient iron to insert into the protoporphyrin ring to form heme. Bone marrow sideroblasts are absent. Slight microcytosis, decreased reticulocyte hemoglobin content. |
|
|
Term
| Iron studies at stage 3 of IDA |
|
Definition
| negative iron flow, blood loss can shorten the time for this stage to develop. All iron tests become abnormal, microcytic hypochromic anemia |
|
|
Term
|
Definition
| master iron regulating protein that regulated iron recycling/balance via interaction with ferroportin 1. It is a negative regulator of intestinal iron absorption. Inhibits iron uptake by intestine and blocks export of stored iron in macrophages. Pathologic cause of anemia of chronic disease |
|
|
Term
| IDA and hemoglobin synthesis |
|
Definition
| defect occur in the body’s ability to intake or absorb iron properly. Insufficient iron to insert into protoporphyrin ring to form heme, zinc is inserted instead. Hemoglobin is not formed properly |
|
|
Term
| Sideroblastic anemia and hemoglobin synthesis |
|
Definition
| defects occur in the first enzymatic step in heme synthesis, the formation of ALA. If the first step in heme synthesis is abnormal, then heme and hemoglobin is not properly produced. |
|
|
Term
| ACD and hemoglobin synthesis |
|
Definition
| defect in recycling iron which is caused by a block in mobilization of iron. If iron is not being recycled correctly, then it is not being incorporated into hemoglobin properly. |
|
|
Term
| Clinical features associated with iron deficiency |
|
Definition
| anemia, koilonychias (spoon nails), glossitis (discolorization of tongue), dysphagia (difficulty swallowing), muscle dysfunction, inability to regulate body temperature, gastritis and pica |
|
|
Term
| Laboratory features of Iron deficiency anemia |
|
Definition
| Microcytic and hypochromic erythrocytes, zinc protoporphyrin, all abnormal iron studies, increased myeloid: erythroid ratio in bone marrow |
|
|
Term
| Laboratory features of Sideroblastic anemia |
|
Definition
| normochromic and hypochromic erythrocytes, RDW increased, target cells, Pappenheimer bodies, basophilic stippling, RPI < 2, increased bilirubin, decreased TIBC, erythroid hyperplasia and ringed sideroblasts in bone marrow |
|
|
Term
| Laboratory tests for Iron Deficiency Anemia |
|
Definition
| Peripheral blood smear, iron studies (low Hb, low MCV, low serum iron, high TIBC, low saturation, low ferritin, high transferrin receptor), EP studies, bone marrow |
|
|
Term
| Laboratory tests for Anemia of Chronic Disease |
|
Definition
| peripheral blood smear, iron studies (low hemoglobin, low MCV, low serum iron, low TIBC, low saturation, high ferritin, normal transferrin receptor), bone marrow |
|
|
Term
| Laboratory tests for Sideroblastic anemia |
|
Definition
| peripheral blood (Pappenheimer bodies, target cells, basophilic stippling), bone marrow, molecular studies |
|
|
Term
| Bone marrow analysis in sideroblastic anemia |
|
Definition
| erythroid hyperplasia, megaloblastosis (responsive to folate), erythroblasts appear poorly hemoglobinized (scanty, irregular cytoplasm), macrophages contain increased storage iron, ringed sideroblasts constitute 40% of all erythroblasts with large iron granules that encircle the nucleus, ringed sideroblasts must be present for diagnosis. Hereditary sideroblastic anemia: abnormal granules occur in later stages of erythroblast development. Idiopathic forms: abnormal granules occur in beginning stages of erythroblast development. |
|
|
Term
| Bone marrow analysis in Anemia of Chronic disease |
|
Definition
| increased myeloid to erythroid ratio because decrease in erythrocyte precursors, proportion of younger erythrocytes are increased, poor hemoglobin production, sideroblasts decrease to 30%, macrophages have increased amounts of hemosiderin in the form of course iron aggregates |
|
|
Term
| Bone marrow analysis in Iron deficiency anemia |
|
Definition
| mild to moderate erythroid hyperplasia, decreased M: E ration, total cellularity is decreased, ineffective erythropoietic component, presence of poorly hemoglobinized erythroblasts with scanty irregular cytoplasm, budding, nuclear fragmentation, mutlinuclearity, absence of hemosiderin in the macrophages |
|
|
Term
| What is the significance of finding microcytic anemia in the presence of lead poisoning? |
|
Definition
| Microcytic anemia is not characteristic of Lead poisoning, this could be due to concurrent iron deficiency or alpha-thalessemia in effected population, need to order a diagnosis of iron deficiency. |
|
|
Term
|
Definition
| shorten erythrocyte life span, anemia is the result of marked abnormality in heme synthesis. Lead inhibits enzymes involved in heme synthesis, erythrocyte protoporphyrin is increased, and iron accumulates in the cell. Basophilic stippling, clumped ribosomes, and degenerated mitochondria are characteristic of lead poisoning |
|
|
Term
|
Definition
| is associated with sideroblastic anemia in alcoholics with poor diet, dimorphic erythrocytes population and siderocytes in the peripheral blood; alcohol interferes with hemoglobin synthesis by inhibiting the synthesis of pyridoxal phosphate and activity of uroporphyrinogen decarboxylase and ferrochelatase, Pappenheimer bodies |
|
|
Term
| Treatment for Iron deficiency anemia |
|
Definition
| administer iron (orally, parenteral) and observe for response ( increase of 1 gm/hemoglobin in 1 month, retic response on 3rd day, normal Hb within 6-10 weeks) |
|
|
Term
| reflex-testing pathway when microcytic and/or hypochromic cells are present. |
|
Definition
| If microcytic and hypochromic cells are present this can be characteristic of iron deficiency anemia, a cost-efficient and effective reflex test would be testing for ferritin because ferritin levels are extremely low in iron deficiency anemia. |
|
|
Term
| Iron deficiency anemia laboratory tests show |
|
Definition
|
|
Term
| Sideroblastic Anemia laboratory tests show |
|
Definition
| ALAS2 gene mutations = hereditary sex-linked, secondary to drugs/toxins- lead poisoning/alcoholism, RARS- acquired stem cell disorder, secondary to malignancy- ringed sideroblasts |
|
|
Term
| Anemia of chronic disease laboratory tests show |
|
Definition
|
|
Term
| RBC morphology (common to all) |
|
Definition
|
|
