RBC Enzyme defect

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RBC Enzyme defect
Advisor Thanusak Tatu
BY
Noppakow Sutti 4211032
Piengpaga Ngaojanlar 4211054 Anuwut
Junsoda 4211098
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Metabolic pathway in the Erythocyte
Metabolic pathway Functions
1. Embden-Meyerhof pathway



Maintain cellular energy by generating ATP
2. Oxidative pathway or
Hexose monophosphate shunt

Prevent denaturation of the hemoglobin by
molecule oxidation
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Metabolic pathway Functions
3. Methemoglobin reductose pathway
Prevent oxidation of heme iron
Regulates oxygen affinity of hemoglobin
4. Luebering-Rapaport pathway
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Red cell metabolism
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Enzyme in Embden-Meyerhof pathway
AR
Hexokinase (HK)
Mild-Severe anemia
Glucose phosphate isomerase (GPI)
AR
Moderate-Severe anemia
Phosphofructokinase (PFK)
X-linked
Moderate anemia
Triosephosphate isomerase (TPI)
Severe anemia
AR
ARautosomal recessive
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Enzyme in Embden-Meyerhof pathway
Phosphoglycerate kinase (PGK)
X-linked
Moderate- Severe anemia
Pyruvate kinase (PK)
AR
Mild-Severe anemia
Lactic acid dehydrogenase (LDH)
AR
Mild anemia
ARautosomal recessive
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Enzyme in Pentose phosphate pathway
Glucose - 6 - phosphate dehydrogenase (G - 6 -PD)
X-linked
No-severe anemia
6 - Phosphogluconate dehydrogenase (G - PGD)
AR
No anemia
?
?
Glutathione reductase (GR)
Glutathione synthetase (GSH)
AR
Mild anemia
ARautosomal recessive
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Enzyme in Pentose phosphate pathway
Glutathione peroxidase (GSH - P)
AR
Mild-Moderate anemia
Adenosine triphosphatase (ATPase)
AD
Moderate anemia
ARautosomal recessive , ADautosomal dominant
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Enzyme in Luebering-Rapaport pathway
2,3-Diphosphoglycero-mutase (2,3-DPGase)
AR
Moderate-Severe anemia
ARautosomal recessive
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Case study
Thai boy, ages 20 months, visited the hospital
because of fever with anemia. Three days ago he
had fever and took a tablet of antipyretic drug.
Thereafter, his mother noticed that he became
pale with dark urine.
HISTORY The boy was normally delivered and was
healthy before the symptom developed.His brother
used to have the same disorder as his when he was
young.
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Physical examination
Temperature 38.1oc Pulse rate 70 /
min Body weight 9 kg Symptom pale, weakness,
jaundice, dark urine
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Laboratory finding
CBC
Results Normal values WBC 15,800
5,000-10,000 cells/
cu.mm cells/cu.mm Hb 3.0 g/dl 9.5-14.1
g/dl Hct 9 30-40
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Laboratory finding
Differential WBC Count
Results Normal values Neutrophilic
band form 4
0-5 PMNs 48
40-75 Lymphocyte 46
25-35 Monocyte 2 2-10
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Laboratory finding
Differential WBC Count
Platelet on blood smear Adequate, normal
shape and size and normal stain RBC
morphology Normochromia Anisocytosis
2 Poikilocytosis 3 RBC
fragmentation 2
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Laboratory finding
RBC morphology Microshperocytes 1
RBC with contracted hemoglobin
few Polychromasia 2
NRBC 12/100 WBC
Reticulocyte 20 Inclusion
body negative Heinz body strongly positive Hb
typing A2A
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(No Transcript)
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Laboratory finding
G6PD semiquantitative normal Urinalysis
Appearance slightly cloudy Color
brown pH 6.0 Specific
gravity 1.020 Protein 2
Final diagnosis G6PD DEFICIENCY
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Summary algorithm of the anemia
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Differentiation for diagnosis
1. Hemoglobin H disease
2. Autoimmune hemolytic anemia Coombs test
3. Paroxymal noctrunal hemoglobinuria (PNH)
Hams test
4. Hepatitis
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Test for G6PD deficiency
- Direct stain
1. Heinz body
- Precipitated by APH
2. Methemoglobin reduction test
3. Fluorescent spot test
4. Quantitative assay
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Fluorescent spot test
Principle
The NADPH becomes fluorescent when exposed to
long-wave ultraviolet light. When whole blood is
mixed with G6PD screening reagent, this reduction
reaction takes place if G6PD is present, and the
samples become fluorescent under ultraviolet
light.
NADP NADPH Glucose-6-phosphate
6-Phosphogluconate G-6-PD
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Fluorescent spot test
Results
Normal blood becomes fluorescent G6PD-deficient
samples show little or no fluorescence.
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Quantitative assay
Principle
G6PD catalyzes the reaction that takes place
when G6P is converted to 6-phosphogluconic acid
(6PG). The rate at which NADPH is produced is
measured spectrophotometrically
G6PD G6PDNADP 6PGNADPH
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Quantitative assay
Calculation

• E340

The
/minute x 60,000 G6PD units/mL red
cell suspension
Units/mL red cells
x109
G6PD activity (in units/109 red cells)
Red cell count
Reference Range
6.5 - 7.9 units/109 cells.
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Pathophysiology of G6PD deficiency and hemolysis
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Oxidant damage of red cells
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Clinical symptoms of G6PD deficiency
1. Acute hemolytic anemia
2. Drug - Induced hemolytic anemia
3. Infection - Induced hemolytic anemia
4. Hemolysis - Induced by acidosis
5. Congenital Nonspherocytic hemolytic anemia
6. Favism
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Treatment
1. Avoid exposure to drugs and oxidant known to
trigger hemolysis
2. Treament
3. Transfusion therapy
4. Prevent hyperkalemia and lost of water
and electrolyte
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Treatment
5. In the newborn, consider with
hyperbilirubinemia
6. Antioxidant vitamin E
7. Suggestion
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Primaquine for malarial treatment in
G6PD-deficiency can cause acute hemolysis