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11 Cards in this Set
- Front
- Back
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Etiology of Glucose-6-phosphate dehydrogenase deficiency
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X-linked recessive hereditary disorder
Several variants exist follows Malaria belt most common enzyme deficiency in world |
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3 common variants of G6PD
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1. G6PD A- (individuals of African descent)
2. G6PD Mediterranian (ind. of Greek ancestry 3. G6PD Canton (assoc. w/ of SE Asian ancestry) |
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Pathophysiology of G6PD
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1. deficiency of G6PD prevents reduction of NADP to NADPH.
2. inadequate NADPH prevents production of glutathione which protects against oxidants. 3. Glutathione exhausted under oxidative stress, exposing RBCs to splenic sequestration (remove Heinz bodies) |
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Sources of oxidative stress leading to G6PD deficiency related HEMOLYTIC ANEMIA
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exposure to drugs or other substances:
primaquine (anti-malarial), broad beans (fava beans), Sulphonamide antibiotics, severe infection |
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Clinical findings of G6PD
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most people asymptomatic, not anemic
During Hemolytic episodes: -sudden anemia, abdominal & lower back pain, dark urine from hemoglobinuria, hemoglobinemia, jaundice |
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Lab findings of G6PD
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NORMOCYTIC, NORMOCHROMIC anemia
INCREASED retics polychromasia, bite cells (from splenic sequestering), schizocytes Heinz bodies (in supravital stain) Fluorescence of NADPH confirmed by G6PD assay |
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Etiology of Pyruvate Kinase deficiency
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inherited autosomal recessive disorder of affecting RBC survival
decreased production of ATP in embden-meyerhof pathway |
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Pathophysiology of PK deficiency
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ATP required by RBC for cellular integrity, cation gradient, maintenance of Hb in reduced state (ferrous=2+)
lack of PK causes decreased production of ATP ADP + 2PEP --X--> 2Pyruvate + ATP |
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Clinical findings of PK deficiency
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mild to moderate anemia w/ splenomegaly
jaundice intermittent dark urine GALLSTONES onset can happen at any age (earlier age discovered=more severe) |
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Lab findings of PK deficiency
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NORMOCYTIC, NORMOCHROMIC anemia
INCREASED retic polychromasia, poikilocytosis Fluorescence - persistence of fluoresence indicated PK deficiency Quantitative PK assay definitive test |
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Methemoglobin Reductatse Deficiency characteristics
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-Hereditary condition
-Enzyme deficiency results in increase in methemoglobin -CYANOSIS -benign course of disease |
