Sickle Cell Flashcards
What type of genetic inheritance is sickle cell disease?
Autosomal recessive
Sickle cell disease requires two copies of the mutated gene to manifest.
What is the specific mutation associated with sickle cell disease?
Glutamic acid to valine missense mutation on the beta-chain
This mutation alters the structure of hemoglobin.
What is referred to as sickle cell trait?
Carrier status (one mutation)
Individuals with sickle cell trait typically experience less severe symptoms compared to those with sickle cell anemia.
What are common presentations of sickle cell crises?
Abdominal or chest pain, as well as dactylitis
Dactylitis refers to inflammation of the fingers or toes.
What specific abdominal pain presentation is highlighted for sickle cell crisis?
RLQ pain with low Hb in a child from Libya
This presentation can be mistaken for appendicitis.
What laboratory test is crucial for confirming the diagnosis of sickle cell disease?
Blood smear
A blood smear can reveal sickle-shaped red blood cells.
What conditions notably increase sickling in sickle cell disease?
Dehydration and increased acidity
These conditions can lead to more frequent sickle cell crises.
SE of hydroxyurea
Myelosuppression
(Anemia, thrombocytopenia, neutropenia)
What test is used to diagnose sickle cell disease?
Hemoglobin electrophoresis to detect HbS
HbS refers to sickle hemoglobin, which is the abnormal form of hemoglobin found in sickle cell disease.
What describes the molecular basis for sickling in a patient?
Gain of stabilizing hydrophobic interactions in the deoxygenated form of hemoglobin S
This occurs because valine is more hydrophobic than glutamic acid, leading to hydrophobic interactions that promote sickling.
What happens to the beta chain in the sickling process?
The beta chain slips into a complimentary hydrophobic pocket on the alpha chain
This interaction contributes to the sickling of red blood cells.
What is the effect of hydroxyurea on sickle cell disease?
Increases HbF and can reduce recurrence of sickle crises
The presence of more HbF means there is less HbS, which helps alleviate the symptoms of sickle cell disease.
Fill in the blank: The presence of more HbF in sickle cell patients means there is fractionally less _______.
HbS
