Master the board step 3

Pediatrics
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Routine care consists of the following measures:
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Penicillin prophylaxis beginning at 3 months until 5 years of age
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Immunizations: Regular plus pneumococcal at age 2 months, influenza
at 6 months then yearly, and meningococcal at 2 years
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Daily folate supplementation
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Bone marrow transplant is the only definitive treatment. It has a mortality
rate of 10 percent.
Beta Thalassemia Major (Cooley Anemia)
Beta thalassemia results from absent or reduced synthesis of beta chains of
hemoglobin. Two alleles are responsible for production of the beta globulin
protein. Beta thalassemia minor is caused by a mutation in one allele; beta thalassemia
major is caused by mutations in both. Beta thalassemia major presents
in second month of life with the following:
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Progressive anemia, hypersplenism, and cardiac decompensation (Hb
< 4 mg/dL)
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Expanded medullary space with increased expansion of face and skull
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Extramedullary hematopoiesis
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Hepatosplenomegaly
Diagnostic Testing
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Best initial and most specific test: Hemoglobin electrophoresis—HbF
increased, variable increased HbA 2 , absent or reduced HbA. (Excess alpha
globin chains → alpha tetramers form → increase in HbF.)
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Severe anemia, low reticulocytes, increased nucleated RBCs, microcytosis
(MCV 55–80 FL), markers of hemolysis (increased indirect bilirubin, LDH,
decreased haptoglobin)
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Increased serum ferritin and transferrin saturation
Treatment
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Transfusion therapy to maintain Hb > 9 g/dL
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Iron chelation: Deferoxamine (usually started before 8 years) plus vitamin C
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Splenectomy: Hypersplenism is common. Splenectomy is usually deferred
until age 5.
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Routine care consists of the following measures:
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Folate supplementation
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Vaccinations: Pneumococcal vaccine, hepatitis B vaccine, daily penicillin
prophylaxis
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Growth hormone: Excess iron is related to deficiency in growth hormone.
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Bone marrow transplantation is curative.
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