Hemoglobinopathies

Question 1

Definition

Answer 1

• genetic disorders that affect the structure of Hb within RBCs, leading to reduced quality or quantity of effective Hb
• SCD
• Thalassemia

Question 2

SCD

Answer 2

• Homozygous hemoglobin S (HbSS), most common type of sickle cell disease
• caused by a mutation in the beta-globin gene (HBB)

Question 3

Signs/symptoms of SCD

Answer 3

• vaso-occlusive complications
  – painful episodes, stroke
  acute chest syndrome, priapism, liver disease, splenic sequestration, leg ulcers, osteonecrosis,
  – complications of hemolytic anemia (e.g., cholelithiasis and aplastic anemia related to parvovirus B19 infection)
  – Haemophilus influenzae and Streptococcus pneumonia infections; osteomyelitis (Staphylococcus aureus or salmonella)

Question 4

Crisis of SCD

Answer 4

• pain control
• fluid resuscitation
• oxygen
• abx
• blood transfusion (exchange transfusion)

Question 5

Treatment

Answer 5

• hydroxyurea
• immunization of encapsulated bacteria
• SUSTAIN study - crizanlizumab (monoclonal ab to p-selectin) - associated with lower rate of SC related pain crises
• L-glutamine
• Voloxator

Question 6

Thalassemia

Answer 6

• alpha and beta thalassemia - genetic abnormalities of hb synthesis
• may have no symptoms or mild anemia
• B thalassemia major may require medical support/blood transfusion