What is the major component of normal adult blood hemoglobin?
Hemoglobin A (α2β2)
What globin chains are present in fetal hemoglobin (Hb F)?
Gamma (γ) chains
What are the two types of thalassemia based on chain synthesis?
α-thalassemia and β-thalassemia
Where is β-thalassemia more common?
Mediterranean region
Where is α-thalassemia more common?
Far East
What do thalassemia syndromes result from?
Reduced synthesis of α and β chains
What causes α-thalassemia traits?
Loss of one or two genes
What is the red cell count in α-thalassemia traits?
Over 5.5 × /L
What is the typical presentation age for thalassemia major?
Within the first year
What happens to HbF production after 3 months in thalassemia major?
HbF production wanes
What are the common symptoms of thalassemia major?
Failure to thrive, poor feeding, pallor
What is the hemoglobin range in thalassemia major at diagnosis?
3-8 g/dl
What is the recommended treatment for thalassemia major?
Lifelong regular blood transfusions
How often are blood transfusions typically administered for thalassemia major?
Every two to five weeks
What is the target pretransfusion hemoglobin level for thalassemia major?
Above 9–10.5 g/dl
What are the hematologic findings in thalassemia major?
Moderate to severe anemia, microcytic hypochromic RBCs
What is the main indication for splenectomy?
Splenomegaly causing mechanical problems or excessive transfusion needs.
What is the recommended daily dose of folic acid?
5 mg daily.
Who should be screened by genetic testing in sickle cell disease?
Parents and other siblings.
What additional therapy may patients with osteoporosis need?
Increased calcium, vitamin D, bisphosphonate, and appropriate endocrine therapy.
What causes sickle cell disease?
Inheritance of the sickle β-globin gene.
What is the sickle β-globin abnormality caused by?
Substitution of valine for glutamic acid in position 6 of the β chain.
What are the four main types of sickle cell crises?
1) Thrombotic crises 2) Sequestration crises 3) Aplastic crises 4) Haemolytic crises.
What is the most serious organ damage in sickle cell disease?
Brain damage, with a stroke occurring in 7% of patients.
What common ulcer is associated with sickle cell disease?
Ulcers of the lower legs due to vascular stasis and local ischaemia.
What happens to the spleen in sickle cell disease over time?
It is enlarged in infancy but often reduced in size later due to infarcts (autosplenectomy).
What test is required to diagnose sickle cell disease?
Detection of HbS through haemoglobin electrophoresis.
What is a key part of general management for sickle cell disease?
Analgesia, rehydration, oxygen, and consider antibiotics if infected.
What should be avoided in sickle cell disease treatment?
Iron therapy and intra-articular steroids due to risk of crisis.
What is sickle cell trait?
A benign condition with no anaemia and normal red cell appearance.
What is the most common symptom of sickle cell trait?
Haematuria, thought to be caused by minor renal infarcts.
What percentage of total haemoglobin does Hb S represent in sickle cell trait?
25 to 45%.
What are the normal percentages of adult haemoglobins?
HbA: 96-98%, HbA2: 0.5-3.2%.
What causes a-thalassaemia traits?
Loss of one or two genes, usually not associated with anaemia.
What are the lab findings in a-thalassaemia traits?
Low MCV and MCH, red cell count over 5.5 x 10^6 /L.
What is required for a definitive diagnosis of a-thalassaemia?
DNA analyses, as haemoglobin electrophoresis is normal.
What is produced from the synthesis of chains?
Cere ic Bory chain
What are the types of tetramers formed?
B tetramers and y tetramers
What is represented by BY(HbH) and yA(Hb Barts)?
Types of hemoglobin chains
Where are these chains present?
In developing normoblasts
What is the effectiveness of erythropoiesis?
Moderately ineffective erythropoiesis
How often are blood transfusions typically administered for thalassemia major?
Every two to five weeks
What are the hematologic findings in thalassemia major?
Moderate to severe anemia, microcytic hypochromic RBCs
What is the main indication for splenectomy?
Splenomegaly causing mechanical problems or excessive transfusion needs.
What additional therapy may patients with osteoporosis need?
Increased calcium, vitamin D, bisphosphonate, and appropriate endocrine therapy.
What is the sickle β-globin abnormality caused by?
Substitution of valine for glutamic acid in position 6 of the β chain.
What are the four main types of sickle cell crises?
1) Thrombotic crises 2) Sequestration crises 3) Aplastic crises 4) Haemolytic crises.
What is the most serious organ damage in sickle cell disease?
Brain damage, with a stroke occurring in 7% of patients.
What common ulcer is associated with sickle cell disease?
Ulcers of the lower legs due to vascular stasis and local ischaemia.
What happens to the spleen in sickle cell disease over time?
It is enlarged in infancy but often reduced in size later due to infarcts (autosplenectomy).
What test is required to diagnose sickle cell disease?
Detection of HbS through haemoglobin electrophoresis.
What is a key part of general management for sickle cell disease?
Analgesia, rehydration, oxygen, and consider antibiotics if infected.
What should be avoided in sickle cell disease treatment?
Iron therapy and intra-articular steroids due to risk of crisis.
What is the most common symptom of sickle cell trait?
Haematuria, thought to be caused by minor renal infarcts.
What are the lab findings in a-thalassaemia traits?
Low MCV and MCH, red cell count over 5.5 x 10^6 /L.
What is required for a definitive diagnosis of a-thalassaemia?
DNA analyses, as haemoglobin electrophoresis is normal.
Are you sure you want to delete 0 flashcard(s)? This cannot be undone.
Select tags to remove from 0 selected flashcard(s):
Loading tags...