Term
Identify the two main pathways by which erythrocytes catabolize glucose |
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Definition
(1)Glycolysis (2)Hexose monophosphate shunt pathway |
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Term
Explain the role of erythrocyte enzymes in maintaining the cell’s integrity |
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Definition
They protect the cell from oxidant damage and provide the cell with energy. GSH maintains Hb in reduced functional state and G6PD maintains glycolysis to provide energy to the cell |
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Term
Describe how deficiencies in these enzymes lead to anemia. |
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Definition
Deficiencies in these enzymes compromise the integrity of the cells membrane. GSH deficiencies cause oxidation of hemoglobin, formation of Heinz bodies, which the spleen removes and leads to extravascular hemolysis. G6PD deficiencies cause decreased ATP and impaired cation pumping which increases osmotic fragility and causes hemolysis |
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Term
Identify the most common erythrocyte enzyme deficiency |
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Definition
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Term
Describe the inheritance pattern for glucose-6-phosphate dehydrogenase (G6PD). |
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Definition
X-linked genetic disorder, more likely to affect males, will only manifest in females is she is homozygous. |
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Term
Explain how the diagnosis of G6PD deficiency is made |
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Definition
Demonstration of an increased G6PD activity by performing esoteric assays 2-3 months after hemolytic episode |
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Term
Recognize the erythrocyte morphology in a Romanowsky-stained blood smear associated with G6PD deficiency |
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Definition
Polychromasia, sphereocytes, small hypochromic cells, schistocytes, bite cells, blister cells, retics, and increased leukocytes, Heinz bodies |
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Term
Identify common compounds that induce anemia in G6PD deficiency |
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Definition
Antimalarial drugs, primaquine |
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Term
Explain the function of glutathione in maintaining cellular integrity. |
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Definition
GSH protects RBC from oxidant damage, maintains Hb in the reduced functional state, and preserves vital cellular enzymes |
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Term
Defects in glycolytic pathways |
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Definition
show extravascular hemolysis because the Heinz bodies precipitate in the cell because they are being oxidized, so the spleen removes them and eventually there is no more membrane and the cell hemolysis in the spleen |
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Term
Defects in hexose-monophosphate shunt pathways |
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Definition
show extravascular hemolysis because of the precipitation of Heinz bodies which is removed by the spleen |
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Term
Acute, acquired HA- clinical findings |
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Definition
hemolytic attacks after infections or expose to drugs, variable hemolysis due to degree of oxidant stress and sex and acute intravascular hemolysis due to drug-induced oxidation |
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Term
Favism- clinical findings |
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Definition
sudden, severe hemolytic episode, usually affect kids, malaise, lethargy, nausea, vomiting, abdominal pain, chills, tremors, fever, hemoglobinuria, jaundice |
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Term
Congenital nonspherocytic HA-clinical findings |
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Definition
clinical findings: class I G6PD variants: chronic hemolysis, compensation, mild anemia, reticulcytosis, |
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Term
Congenital nonspherocytic HA-lab findings |
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Definition
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Term
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Definition
severe hyperbilirubinemia, potential for kerniceterus |
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Term
variants of G6PD lab findings before attack |
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Definition
no anemia, normal blood until hemolytic attack |
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Term
Lab findings after attack |
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Definition
polychrome, sphereocytes, small hypochromic cells, schistocytes, bite cells, blister cells, retics, and leukocytes |
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Term
Diagram the reaction catalyzed by pyruvate kinase |
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Definition
Ending step in glycolysis: 2 phosphoenolpyruvate -> 2 pyruvate (ADP --> ATP) |
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Term
explain how a defect of PK can cause hemolysis. |
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Definition
If PK is deficient then intermediate of glycolysis will build up, the rappaport leubering shunt will produce more 2, 3-BPG |
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Term
Recognize erythrocyte morphology associated with pyruvate kinase deficiency |
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Definition
Normochromic/normocytic, retics, echinocytes, nRBCs |
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