Pathophysiology - Sickle Cell Disease Flashcards
Sickle cell disease is a mutation to hemoglobin resulting in malformed _______.
Red blood cells (erythrocytes)
Sickle cell crises is a condition that includes multiple sub-conditions, including:
- vaso-occlusion
- aplastic crisis
- sequestration crisis
- haemolytic crisis
In sickle cell disease, pain arises from _______ during a crisis.
- vaso-occlusion 2/2 to sickled cells becoming “knotted “ together in blood vessels.
In SCD, a change in one amino acid produces hemoglobin____
Hemoglobin-S (HbS)
What is the specific AA in change and on what chromosome does the base pair change?
Glutamic acid —> Valine, Chromosome 11
What people groups are often affected by SCD?
Persons of the following descents:
- Sub-Saharan African
- South Asia
- Middle East
- Mediterranean
Explain “hemoglobin polymerization” in the case of SCD.
- Changes to Hb to HbS result in the inability of erythrocytes to deform.
- These “sickled” red blood cells form aggregates in vessels, producing decreased blood flow.
- Increased HbS polymerization and recruitment of inflammatory mediators (including NO) –> reperfusion injury
Continue with this article:
https://www.ncbi.nlm.nih.gov/books/NBK482384/
Okay
According to a study from 2015-2014 in CA emergency departments, what age group has the highest number of ED visits for SCD?
17-59 yo
Sickle Cell disease is a(n) _______ disorder.
autosomal recessive
Explain the genotype of both sickle cell carriers and diseased persons
HbSA (carrier) - HbSickleAdult
HbSS (SCD) - HbSickleSickle
Sickle Cell Hb is an adaptation for what other disease?
Malaria
1 in every ____ African-American births in the US have SCD
500
Hydroxyurea helps return RBCs to a normal shape. How?
Switches hemoglobin from HbS to HbF (fetal-Hb).
HbF is more flexible due to a change to an alanine or glycine AA at position 136 in the gamma-chain of the Hb.
(https://www.ncbi.nlm.nih.gov/books/NBK500011/)
