Haemoglobinopathies

Question 1

What are Haemoglobinopathies?

Answer 1

inherited disorders of globin, the protein component of haemoglobin

Question 2

What are the main groups of Haemoglobinopathies?

Answer 2

• thalassaemia syndromes or variant Hbs
• Mutations in genes coding for the globin proteins that alter protein output produce the thalassaemia syndromes. Mutations in the globin genes that lead to abnormal proteins are called variant Hbs.

Question 3

How are thalassaemias inherited?

Answer 3

autosomal recessive

Question 4

What is Alpha thalassemia major?

Answer 4

both alpha-globin genes on the same chromosome are deleted

Question 5

What is Alpha thalassemia minor?

Answer 5

which 1 of the 2 alpha-globin genes on the same chromosome is deleted or mutated

Question 6

What is ß thalassemia major?

Answer 6

complete absence of beta-globin production, are usually nonsense, frameshift, or splicing mutations

Question 7

What is ß thalassemia minor?

Answer 7

some beta-globin production are most often in the promoter regions or splicing defects

Question 8

What is sickle cell anaemia?

Answer 8

autosomal-recessive single gene defect in the beta chain of haemoglobin (HbA), which results in production of sickle cell haemoglobin

Question 9

What are the clinical features of Alpha thalassemia?

Answer 9

anaemia and increased haemolysis, microcytosis, hypochromia

Question 10

What are the clinical features of ß thalassemia?

Answer 10

Clinical manifestations are usually seen only after the normal transition from fetal haemoglobin.

anaemia and a compensatory erythroid hyperplasia.

Question 11

What are the symptoms of Alpha thalassemia?

Answer 11

• Anaemia
• jaundice
• Splenomeagly

Question 12

What are the symptoms of ß thalassemia?

Answer 12

Often asymptomatic but may have heptaospelonmeagly, failure to thrive, lethargy, abdominal distension

Question 13

What are the symptoms of sickle cell anaemia?

Answer 13

vaso-occlusive crisis

crisis may present as skeletal pain due to bone infarction or avascular necrosis, especially of the hip or shoulder

Question 14

What are DDx for Alpha thalassemia?

Answer 14

• Iron deficiency anaemia
• ß thalassemia
• haematological malignancies

Question 15

What are DDx for ß thalassemia?

Answer 15

• Pyruvate kinase deficiency
• Congenital dyserythropoietic anaemia • Mild iron deficiency anaemia
• Haemolytic anaemia
• alpha-thalassemia

Question 16

What are DDx for sickle cell anaemia?

Answer 16

• Gout
• Septic arthritis
• Avascular necrosis • Osteomyelitis