3.20 CHESNEY Thalassemias Flashcards Preview

HEME: Yetter > 3.20 CHESNEY Thalassemias > Flashcards

Flashcards in 3.20 CHESNEY Thalassemias Deck (10):
1

Why do thalassemias exist?

Give carry advantage to survival in certain regions

2

Why is there anemia?

With lack of beta, there will be excess alpha which will ppt out and deform and destroy the RBC (hemolytic anemia)
-BM message to increase RBC production with quick turnover could lead to iron overload

3

What distorts bones in beta?

Increased production in BM can lead to hyperplasia which can lead to thinning of the bones and deformities of the bones
-Usually seen in major

4

What happens to the liver and spleen with Beta

-both are enlarged
-Spleen is overworked b/c of hemolytic anemia and trying to clear everything
-Liver is trying to help and enlarging, could see Fe overload
-Major

5

What are some consequences of Iron overload

-More likely to get infection
-Healing problems which could also lead to infection
-Ulcers on the ankles
-take out spleen, but very dangerous to do b/f the pt is 6y.o.
-Removal of spleen will make pt susceptible to encapsulated bacteria

6

Why iron overload?

-Transfusion Iron (no excretion mech)
-Increased absorption b/c of anemia and signaling to make more RBC
-Iron overload in liver can lead to hepatocellular carcinoma from the cirrosis damage

7

Hypercoaguable?

Membrane damage by alpha hemichromes and oxidant stress
Phosphatidylserine exposed to outside
--recognition site for cell removal during apoptosis
--increased thrombin production
-Increased plasma free Hgb
-Increased platelet activation (esp w/ stasis)
Thrombotic complication reduced with transfusion therapy

8

Why variable presentation?

-Outcome depends on what the pt can make, any beta at all is better than none
-and ability to upregulate other froms of Hgb

9

Peripheral Smear

Target Cells and basophilic stippling, hypochromatic
-means bm is cranking out new cells rapidly and the spleen is overworked b/c it would have otherwise clear these.
-With major will see nucleated RBC

10

Diagnosis

Present with Tiredness, low MCV, normal RDW
-Normal or high iron
-HPLC and electrophoresis with beta to look for increased A2 and other conc of other Hgb's