Transcript Hematology Final Case Study 3 Merged

Case 3
Benjamin Haro, John Kang, Annelise Lupica
Case Summary
25-year-old African American male soldier
in the process of being deployed to West
Africa, took anti-malarial prophylaxis,
primaquine, three days before leaving
 Within 24 hours of taking the medication,
the patient was hospitalized for fever, chills,
and general malaise
 His physical exam seemed normal, without
acute stress, with no significant family
history or drug allergies
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Key Information Pointing to Diagnosis
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Decreased Hemoglobin at 9.1 g/dL
Decreased RBC count at 3x1012/L
 Value derived from Hct/RBC=MCV
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Bite Cells and spherocytes in peripheral blood
Onset of anemia after administration of
primaquine
Blood smear indicating shortened RBC life
span, caused by oxidative damage
Positive G6PD deficient spectrophotomertric
assay, after the cells had aged
The Diagnosis for Case 3

Glucose-6-Phosphate Dehydrogenase
Deficiency (G6PD deficiency)
 Also known as Heinz Body Anemia
Pathophysiology of G6PD Deficiency
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Acute intravascular hemolysis
occurs when exposed to acute
oxidative stress, such as certain
drugs, fava beans, infection, and
birth
In normal cells, G6PD catalyzes
the first step in the hexose
monophosphate shunt
Glucose-6-phosphate is oxidized
to 6-phosphogluconate in a
coupled reaction in which NADP
is reduced to NADPH
NADPH in turn reduces a
glutathione aggregate to a
glutathione monomer
Because G6PD deficient patients
cannot reduce to glutathione,
oxidative damage precipitates
Heinz bodies
Pathophysiology of G6PD Deficiency
G6PD activity is highest in
young RBCs and decreases
as the cell ages.
 Once the cell starts to age
enzyme activity decreases
and Heinz bodies attach to
the RBC membrane.
 Heinz bodies lead to
decreased RBC survival time.
 Normally the bone marrow is
able to compensate for the
decreased RBC survival time.
 Oxidative drugs (anti-malarial)
can cause acute oxidative
stress and lead to acute
intravascular hemolysis.
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Diagnostic Tests for G6PD Deficiency
CBC
 Peripheral Blood Smear (stained with new
Methylene Blue)
 Spectrophotometric Assay
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 A measurement of the activity of the G6PD
enzyme
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Rapid fluorescent spot test (Beutler
fluorescent spot test)
 Detects the generation of NADPH from NADP
Therapy and Prognosis for G6PD
Deficiency
Avoid or discontinue use of an oxidant
drug
 Transfusion after a hemolytic episode
 The prognosis for patients with G6PD
deficiency is good with no complications
as long as the use of oxidant drugs is
discontinued.
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Prevention of G6PD Deficiency
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Avoiding oxidant drugs and fava beans
(if diagnosed with Favism) can avoid the
anemic effects of G6PD Deficiency
Take Home Message
The diagnosis is Glucose-6-Phosphate
Dehydrogenase Deficiency
 Typical symptoms are anemia, bite cells,
hemoglobinuria, and jaundice
 The cause of the disease is deficiency in G6PD,
typical of older RBCs
 Diagnostic tests include spectrophotometric assay
and rapid fluorescent spot test
 Treatment is discontinuation of oxidizing drugs, and
transfusion
 Prognosis is good if oxidant drugs are discontinued
 Prevention is avoidance of oxidant drugs and fava
beans
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References
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Cappellini, M. D., & Fiorelli, G. (2008). Glucose-6-phosphate
dehydrogenase deficiency. Lancet 371(9606), 64-74.
doi:10.1016/S0140-6736(08)60073-2
Carter, S. M. (2009). Glucose-6-Phosphate Dehydrogenase
Deficiency. Medscape Reference WebMD LLC. Retrieved
from http://emedicine.medscape.com/article/200390overview
G6PD Deficiency. (2010). In g6pddeficiency.org. Retrieved
from http://g6pddeficiency.org/index.php
Harmening, D.M. (2009). Hemolytic Anemias:
Intracorpuscular Defects: II. Hereditary Enzyme
Deficiencies. Clinical Hematology and Fundamentals of
Hemostasis 5th Edition (197-200). Philadelphia, PA: F. A.
Davis.
McQueen, N. L. (2011). Hemolytic Anemias Due to Other
Intracorpuscular Defects [PowerPoint slides]. Retrieved from
http://instructional1.calstatela.edu/nmcquee/MICR410/
Point Spread
Case summary
5
Key Information pointing to Diagnosis
15
Diagnosis
5
Pathophysiology of the disease
25
Diagnostic tests
10
Therapy
5
Prognosis
5
Prevention
5
Take home message
5
Are all questions addressed?
10
Appearance
5
Presentation skills (individual)
5
Total
100