Hemoglobinopathies Flashcards
Percentage of HgbA:
30% at birth and 79% by 6-12mon
What are the complications of thalasemia major?
Hemosidrosis - heart: mycardial-siderosis - Liver: hepatosplenomegaly - pancreas: bronze diabetes - anterior pituitary: dealyed puberty + short stature Chronic anemia
Why is there typical thalassemia fascial features
Frontal bossing, nasal brydge depression, maxillary prominance
(Due to the erythroid producing bone being hyperactive for erythropoesis)
How to prevent hemosiderosis in thalassemia patients?
.by iron chelators
What lis hypertransfusion given to patients with thalassemia major?
Regular transfusion every 4 weeks to maintain hgb as 12-13g
“Followed by iron chelator”
Ineffective erythropoesis in thalassemia major is caused by::
Tissue hypoxia
What is the management of thalassemia major?
- hyper transfusion
- deferoxamine
- curative is stem cell transplantation
When patient can tolerate oral medications, what is the best chelator to be given to increase compliance
- defirpone
- deerisorx
What is the definitive treatment of thalassemia major?
Stem cell
Beta thalassemia intermedia percentage:
A1:
A2:
F:
A1: trace
A2: 2%
F: 70
Where do we see target cell?
Beta thalassemia intermedia
What is hemoglobin bart and hemoglobin H?
Hemoglobin bart: gamma globin attach to each other
Hemoglobin H: beta globin attach to each other
The more F hgb in sickle cell indicates:
.
Reticulocyte count and presentation in hemolytic crisis and aplastic crisis
.
How to treat vso-occulsive crisis:
.
Define anemia
Decrease RBC volume, hg concentration, or hematocrit
What is the rate of hemoglobin change in pediatric
High after birth > Decrease > high at 7-12
What is the shape of normal RBC?
Biconcave w\central depression
What is the function of RBC?
Carrying O2 and CO2
When gamma chain decreases what happens to Beta chain
Increase
What is the globin polypeptide that is present all through our life?
Alpha
What forms
HgA - A1 - F?
A: 2a - 2b
A2: 2a - 2d
F: 2a - 2g
Which polypeptide is present before birth in low amount?
Delta and gamma
How many loci of alpha and beta chain?
Alpha: 4 loci
Beta: 1 loci (2 gene)
What is the percentage of HgbF?
70% at birth and trace by 6-12 month
Hgb A2 is
- High in:
- Low in:
Hight: B-thalassemia
Low: IDA and A-thalassemia
What is the clinical hallmark of hemolytic anemia
Jaundice and pallor
What are the hemoglobin in B0 thalassemia
Hg A2 and HgF
2a + 2d - 2a+2g
What is cooley anemia?
B0 thalassemia
What are the clinical mainfestations in B-thalassemia major (B0)
[pallor - irritability - tachycardia - hepatosplenomegaly]
What are the features of thalssemia major?
- frontal bossing, depressed nasal brydge, maxilla prominance (chipmunk)
What is the blood film finding in thalassemia major?
Microcytic hypochromic + fragmented RBC (nucleated RBC) + bizzare shape cells
What are the treatments in thalasemia intermedia?
Hydroxyurea and folic acid but they don’t need blood transfusion
What happens in case of abscence of 3 alpha genes?
Hb H disease
Red cell inclusion and spleenomegaly
What happens in case of abscence of 4 alpha genes?
Hydrops fetalis
Transfusion dependant
In blood smear to differentiate between iron def anemia and
No target cell in IDA instead pencil and cigar cells are found
What is hemoglobin S?
In beta chain instead of having glutamic acid at position 6 it becomes valine
Define sickle cell disease - ss - sc - sb0 - sb+ -
- Hgs is >50% + no Hga1
- hgs <50% + yes hga1
- hbf, hba2, hbs + no hg1
- hgs >45% + small hga1
What happens during oxygenated vs de-oxygenated state in sickle cell
Oxygenated: de-polymarized
De-oxygenated: polymarize. Increase rigidity and adhesivity
Sickle shape and rigidity consequence
Sickle: hemolysis
Rigidity: vaso-occlusive crisis
What do howell jolly bodies indicate?
Dysfunctional spleen
