Term
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Definition
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Term
| What is the most readily available test to differentiate a B12 deficiency from Folic Acid Deficiency? |
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Definition
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Term
| What are the common causes of Macrocytic Anemia? (11) |
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Definition
| DNA synthesis issues: Increased Reticulocytes (from bleeding/RBC destruction), Bone marrow failure, Liver disease, Drugs (methotrexate and hydroxyurea), and Alcohol |
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Term
| Megaloblastic Anemias are associated with what, and a blood smear is characterized by what? (12) |
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Definition
| Impaired DNA synthesis; Blood smear shows MacroOVALocyces, High MCV (100-140), Howell Jolly Bodies, and Hypersegmented Neutrophils (>5 lobes) |
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Term
| Image 13 of macrocytic anemia findings |
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Definition
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Term
| Pathogenesis of Megaloblastic Anemia |
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Definition
| It is a Biochemical defect in DNA synthesis resulting in 1) Delayed nuclear devo, impaired cell division, and unbalanced cell growth, 2) Orderly cytoplasmic maturation, 3) Ineffective erythropoiesis, 4) Intramedullary cell death (RBCs die in marrow) |
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Term
| What are the Bone marrow findings in Megaloblastic Anemia? |
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Definition
| Increased Immature precursors with delicate, open granular chromatin as well as Giant Metamyelocytes |
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Term
| Images of Megaloblastic RBC precursors 17-20 |
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Definition
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Term
| What disorder is often described as the Prototype of Megaloblastic Anemias? |
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Definition
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Term
| PA is a chronic gastritis mediated autoimmune disorder that prevents the release of what? |
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Definition
| Intrinsic Factor from Parietal Cells |
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Term
| How long can Cobalamin stores last? |
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Definition
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Term
| What is the function of Cobalamin? |
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Definition
| It is a Coenzyme that transfers a Methyl group to Homocystiene to form Methionine |
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Term
| Metabolic Reactions involving B12 (see 26) |
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Definition
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Term
| What does Cobalamin combine with in the stomach? |
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Definition
| IF (Intrinsic Factor) AND R factor |
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Term
| What happens once the R-IF-Cobalamin complex reaches the 2nd portion of the duodenum? |
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Definition
| Cobalamin is cleaved from R factors by pancreatic proteases and Free Cobalamin binds remaining IF |
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Term
| What happens when IF-Cobalamin reaches the Ileum? |
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Definition
| The complex is cleaved and absorption of Cobalamin occurs as Transcobalamin (another complex released in portal veinous system) |
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Term
| What is the role of TransCobalamin II? TransCobalamin III? |
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Definition
| TCII Transports protein carrying Cobalamin to peripheral tissues; TCIII carries Cobalamin to the liver where it is excreted into the bile and channeled through the enterohepatic cycle |
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Term
| When will TC III levels be high? |
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Definition
| Myeloproliferative Disorders |
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Term
| *What is Pernicious Anemia associated with? |
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Definition
| Chronic Immunologically mediated Gastritis |
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Term
| *What is the clinical presentation of PA? |
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Definition
| Lemon Yellow complexion with Loss of Position and Vibratory Sense |
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Term
| What are the Neurological Aspects of PA and what term describes them? |
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Definition
| Myelin Degeneration of the Dorsal and Lateral spinal cord columns, Dorsal root Ganglia, and Peripheral nerves; Termed *Subacute Combined Degeneration* |
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Term
| Image of Subacute Combined Degeneration on 37 |
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Definition
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Term
| Laboratory Features of PA including: IF release, Oral absorption of B12, RBC life, Indirect Bilirubin and LDH, Serum B12, Serum/Urinary Homocysteine, Serum/Urinary Methylmalonic acid |
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Definition
| Decreased gastric IF release, Low oral B12 absorption, Decreased RBC survival, Increased serum Indirect Bilirubin and LDH, Low Serum B12, Increased Serum/Urinary Homocysteiene and Methylmalonic acid |
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Term
| What differentiates PA (cobalamin deficiency) from Folate deficiency? |
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Definition
| the increased Serum/Urinary Methylmalonic acid |
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Term
| B12 deficiency is best treated with what? |
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Definition
| IntraMuscular B12 given for life |
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Term
| Is transfusion necessary for B12 deficiency treatment? What other compound needs to be carefully monitored as RBC's are restored when treating PA? |
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Definition
| Rare to have to use Transfusions; Potassium may drop upon RBC replenishment, so it is important to monitor to avoid sudden death |
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Term
| What is the role of Folic Acid? |
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Definition
| It is a catalytic acceptor-donor of one-carbon units (such as methylation of deoxyuridylate > Thymidylate) |
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Term
| Folic Acid is acquired through green leafy vegies and is often deficient in diets with what cooking methods? |
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Definition
| Starchy Fried foods and Long Boiling of Veggies |
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Term
| What is the RDA (recommended Daily Allowance) of Folic acid and how long can stores last? |
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Definition
| 400mcg/day; stores last weeks-months |
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Term
| What are some common causes of Folic Acid Deficiency? |
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Definition
| Dietary deficiency among Alcohol Abusers, Impaired Absorption, Excessive Losses (hemodialysis), and situation with increased requirements like Pregnancy/Growth periods |
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Term
| What are the three Major Drugs that cause Impaired Folate Metabolism? |
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Definition
| Ethanol, Dilantin, and Methotrexate |
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Term
| What is the most helpful Test for Differentiating Megaloblastic Anemia caused by Folate vs Cobalamin Deficiency? |
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Definition
| Serum and Urinary Methylmalonate (high in B12 but not Folate deficiency) |
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Term
| Why should therapy for Folate deficiency not only give Folate but B12? |
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Definition
| If there IS a B12 deficiency, Neurological Deterioration can occur if B12 is not administered |
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