Term
| What are the three major causes of microcytic anemia? |
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Definition
| 1) disorders of iron metabolism and utilization (IDA, ACD) 2) disorders of heme synthesis (sideroblastic, lead poisoning) 3) disorders of globin synthesis (thalessemia) |
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Term
| How much Fe is absorbed from the diet daily? |
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Definition
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Term
| What percent of body iron is bound to plasma transferrin? |
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Definition
|
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Term
| What percent of the body iron is stored? as what? |
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Definition
| 30%, as ferritin and hemosiderin in macrophages in bone marrow, spleen and liver |
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Term
| What percent of body iron is found in circulating RBCs? |
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Definition
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Term
| What is the daily iron loss? |
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Definition
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Term
| 4% of total body iron is in other tissues like... |
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Definition
| muscle, cell enzymes, GI cells |
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Term
| Where in your diet do you get iron? |
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Definition
| heme iron from meat is very efficiently absorbed; non heme iron (fe3+) is the majority of dietary iron from veggies, grains, fortified cereals |
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Term
| What type of iron is absorbed into the GI cell and what type of iron is released from GI cell? |
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Definition
| Fe2+ is absorbed; Fe3+ is let into circulation to bind to transferrin |
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Term
| 1 mL of RBCs = ___ of iron |
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Definition
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Term
| What are the normal quantities of iron stores? |
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Definition
| 1000 mg in men; 400 in women |
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Term
| How much blood/iron is lost during mensturation? |
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Definition
| 20-60 mL of blood; aditional daily requirement of 1 mg of iron |
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Term
| How much iron is needed for pregnancy? |
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Definition
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Term
| TIBC is an indirect measurement of ____. |
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Definition
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Term
| What is measured in serum iron? |
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Definition
| amount of iron bound to transferrin |
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Term
| How do you calculate transferrin saturation? |
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Definition
|
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Term
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Definition
| estimate of body storage iron (single best blood test of iron stores). also increased in inflammatory disorders because its an acute phase reactant |
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Term
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Definition
| free erythrocyte protoporphyrin |
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Term
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Definition
| IDA, ACD, sideroblastic anemia, and lead poisoning |
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Term
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Definition
| serum soluble transferrin receptor; found on cell membranes to transfer iron from plasma TF into cells. soluble form exists in blood which is proportional to the membrane TfR |
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Term
| sTfR is increased in ____ anemia and normal in ____ anemia. |
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Definition
| increased in IDA, normal in ACD |
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Term
| What causes chronic blood loss that leads to iron def anemia? |
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Definition
| GI lesions, menorrhagia, drugs (aspirin, NSAIDS) |
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Term
| What are causes of iron deficiency? |
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Definition
| chronic blood loss, increased requirements, decreased absorption, inadequate intake |
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Term
| When do you have physiologic increased iron requirements? |
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Definition
| infancy, adolescence (growth spurt), menstruating women, pregnancy, lactation |
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Term
| What causes decreased iron absorption? |
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Definition
| achlorhydria, gastric bypass or gastrectomy, celiac sprue, PICA |
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Term
| What epithelial abnormalities are caused by IDA? |
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Definition
| koilonychia, glossitis, tongue atrophy, angular cheilosis, esophageal webs with dysphagia (plummer-vinson/paterson-kelly) |
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Term
| What is the earliest lab abnormality of iron deficiency? |
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Definition
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Term
| What are the lab values of iron deficient erythropoiesis versus IDA? |
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Definition
decreased serum iron, increased TIBC, and decreased Tf saturation
normal hgb/hct
IDA= decreased Hgb/hct/MCV, hypochromic |
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Term
| what platelt abnormality is possible with IDA? |
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Definition
|
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Term
| What is the RBC and RDW in IDA? |
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Definition
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Term
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Definition
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Term
| How long does it take for body to respond to iron tabs in IDA? |
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Definition
| 3 days for retic increase, 5-7 for max retic response, hgb increases 2g/dL within 3-4 weeks (may take several months for Hgb to return to normal) |
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Term
| Why do you continue iron therapy for several months after hgb values return to normal? |
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Definition
|
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Term
| Where does iron accumulate in SA? |
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Definition
| perinuclear mitochondria of developing NRBCs |
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Term
| What causes sideroblastic anemia? |
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Definition
hereditary (rare, usually x-linked)
acquired: myelodysplastic syndrome (refractory anemia with ringed sideroblasts- RARS), drugs (reversible; alcohol, anti-tuberculous agents= isoniazid, chloramphenicol) |
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Term
| What is hte peripheral smear morphology of sideroblastic anemia? |
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Definition
| dimorphic RBC population (both hypochromic/microcytic and N/N), pappenheimer bodies |
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Term
| What is the pattern of inheritance of hemochromatosis? |
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Definition
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Term
| What is the Tf saturaiton in hereditary hemochromatosis? |
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Definition
|
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Term
| What parenchymal diseases are associated with hereditary hemochromatosis? |
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Definition
| diabetes, cardiomyopathy, arthritis, skin pigmentation, hypogonadism/pituitary dysfunction |
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Term
| How do you diagnose hereditary hemochromatosis? |
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Definition
| gene detection (C282Y and H63D) and by liver biopsy to assess degree of iron deposition and presence of fibrosis/cirrhosis; bone marrow not useful |
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Term
| What are complications of hereditary hemochromatosis? |
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Definition
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Term
| Hereditary hemochromatosis is a ______ anemia. |
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Definition
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Term
| What anemia results in increased FEP and increased delta aminolevulinic acid? |
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Definition
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Term
| What is the morphology of RBCs in lead poisoning? |
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Definition
N/N or hypochromomic/microcytic
basophilic stippling |
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Term
| Name common sources of lead exposure. |
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Definition
| pain chips, gasoline sniffing, storage batteries, glazed pottery |
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Term
| What are clinical symptoms of lead poisoning? |
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Definition
| abdominal colic, renal problems, peipheral neuropathy, encephalopathy (seizures and MR),lead line in gums |
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Term
| Children with lead poisoning should be screened for ______ deficiency. |
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Definition
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Term
| What causes normochromic normocytic anemia? |
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Definition
| ACD (maybe hypochromic/microcytic), anemia of chronic renal disease, anemia of endocrinopathies, myelophthisic anemia, aplastic anemia, acute blood loss (before reticulocytosis) |
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Term
| ACD is associated with what underlying diseases? |
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Definition
| inflammation, infection or malignancy |
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Term
| What are the two most common types of anemia? |
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Definition
| ICD then ACD (ACD is MC in hospialized pts) |
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Term
| How does chronic disease cause anemia? |
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Definition
| inhibition of erythropoiesis by cytokines and block in iron transfer from BM macrophages to erythroid cells |
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|
Term
| What is the serum Fe in ACD? |
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Definition
|
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Term
| What is the TIBC and % Tf sat in ACD? |
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Definition
| decreased TIBC, decreased Tf sat |
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Term
| What does the bone marrow look like in ACD? |
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Definition
| increased storage in Macrophages |
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Term
|
Definition
| tx underlying dz; recombinant erythropoietin |
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Term
| Describe peripheral smear of anemia of chronic renal failure? |
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Definition
| N/N anemia with inadequate retic response; may see burr cells |
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Term
| What causes anemia in chronic renal failure? |
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Definition
| decreased erythropoietin, marrow suppresion d/t retained uremic toxins, iron/folate def from dialysis |
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Term
| What causes myelophthisic anemia? |
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Definition
| neoplasms (myelofibrosis, leukemias, lymphomas, myeloma, metastatic carcinoma) non-neoplastic processes (granulomatous inflammation= TB, fungi, sarcoidosis; metabolic storage disease) |
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Term
| Describe peripheral blood smear of pts with myelophthisic anemia? |
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Definition
| N/N anemia with NRBCs and immature WBCs (leukoerythroblastic anemia) |
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Term
| What types of anemia requires a bone marrow biopsy for dx? |
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Definition
| myelophthisic and aplastic anemia |
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Term
| What are symptoms of aplastic anemia? |
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Definition
| anemia with decreased retic count, infections, bleeding |
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Term
| Name an example of an inherited aplastic anemia. |
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Definition
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Term
| What causes most 60-70% of cases of acquired aplastic anemia? |
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Definition
| primary/idiopathic (immune mediated suppresion of hematopoiesis) |
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Term
| What are secondary causes of aquired aplastic anemias? |
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Definition
| drugs, viral infection, radiation, toxins/chemicals, paroxysmal nocturnal hemoglobinuria (PNH) |
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Term
| What drugs cause aplastic anemia? |
|
Definition
expected= chemo
unexpected/idiosyncratic= chloramphenicol, phenylbutazone, gold, antibiotics, anticonvulsants |
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|
Term
| What toxins/chemicals can cause aplastic anemia? |
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Definition
| benzene, solvents, insecticides |
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|
Term
| What viral infections cause aplastic anemia? |
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Definition
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Term
| What studies should you get to work up an anemia of unkown etiology? |
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Definition
| serum iron, TIBC/Tf, serum ferritin, serum B12, serum folate, retic count |
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