sickle cell anemia Flashcards
(24 cards)
what is the pathology associated with sickle cell anemia ?
autosomal recessive disorder
associated with a missense mutation with glutamic acid to valine switching
abnormal beta hemoglobin chains
SINGLE BASE SUBSTITUTION
what is the composition of someone who has the sickle cell anemia trait ?
one normal beta globin and one abnormal
HbS disease
what is the Hb composition in utero and at birth ?
high HbF and low HbA
what is the pathology associated with the formation of a sickle cell ?
when HbS is deoxygenated it polymerizes and forms a sickle shape
clinically what are the 2 major problems associated with sickle cell anemia ?
hemolytic anemia
vaso-occlusive crisis
what is the presentation associated with vaso occlusive crisis ?
dactylitis
acute pain crisis
splenic sequestrian
avascular necrosis
what is the common initial presentation of sickle cell disease in children ?
dactylitis
what does the avascular necrosis in sickle cell anemia usually present as ?
avascular necrosis of the femoral head
what is the treatment for sickle cell crisis ?
hydration and pain medications
what are the features associated with splenic failure in sickle cell anemia ?
howell-jolly bodies will appear in peripheral blood smear
which are basophilic nuclear remnants
what type of infections are more associated with sickle cell disease ?
1 - infection by encapsulated bacteria
like s pneumonia , so patient must be vaccinated
2- osteomyelitis from salmonella
what is the problem associated with splenic sequestration crisis ?
risk of hypovolemic shock especially in children
what is the leading cause of death associated with sickle cell disease in adults ?
acute chest syndrome
often triggered y infection
where is the affection when it comes to SCD and renal affection ?
occlusion of the vasa recta in the renal medulla - is associated with papillary necrosis
what are the causes of papillary necrosis generally speaking ?
NSAIDS
NSAIDS
Sickle cell anemia
Acute pyelonephritis
Interstitial nephritis
Diabetes
what is the treatment associated with sickle cell anemia ?
hydroxyurea
immunization
bone marrow transplant
what is the one exception of sicklin in sickle cell trait ?
in the renal medulla
increased risk in renal medullary carcinoma
what are the methods of diagnosis of sickle cell disease ?
electrophoresis - presence of HbS
sickling test - forms a suspension
why is hydroxyurea used ?
increases the amount of HBF and hence decreases the amount of HbS
what is the pathology associated with hemoglobin C ?
rare mutation of the beta gene
glutamic acid replaces lysine
mild anemia
what are the diseases associated with increased MCHC ?
hereditary spherocytosis
hemoglobin C disease
what is found on smear of HbC disease ?
HB C crystals
what does heterozygote advantage lead to in sickle cell anemia ?
resistance to malaria
what are the conditions associated with a higher rate of sickling ?
dehydration and acidic environments
