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Discussion Starter · #1 ·
A 17-year-old male who recently emigrated, with his family, from Cambodia presents in your clinic for continued management of his anemia. His peripheral smear is shown. A medical report indicates the presence of hemoglobin α2δ2.
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Which is the likely diagnosis?
A. Two deletions of the β-globin gene
B. Three deletions of the β-globin gene
C. One deletion of the α-globin gene
D. Two deletions of the α-globin gene
E. Iron deficiency anemia
 

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I think mentioning the hemoglobin is just a distractor since in normal conditions it can be found in small percentages, plus the smear shows microcytic hypochromic anemia, with Iron deficiency being the most probable diagnosis

I think that if Hemoglobin was significant then it would be mentioned in a more subjective way - the exact percentage for example

this is what I think ... any other ideas guys?
 

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The question doesnt say how much α2δ2 is present in the peripheral blood. So isnt that a relevant information??or is it just a distractor?:eek:

Thalassemia wont present like this???
Please advise...
Its just a distractor. During fetal life a minor adult type haemoglobin called Haemoglobin A2 (α2δ2) is produced. The level of Haemoglobin A2 is between 2.2% - 3.5% and remains at this level at birth and through out adulthood.
 

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Discussion Starter · #9 ·
Guys m sorry didnt post the answer for this question.... was abit busy during these days...

The correct answer is D.
This patient has a hypochromic, microcytic anemia. Classically, the presence of HbA2 (α2δ2) suggests β-thalassemia minor. However, this is not one of the answer choices.

The learning point is that HbA2 is present in mild alpha-thalassemia – there’s not enough of an alpha-chain deficiency to prevent the formation of HbA2. Hence, the correct answer is 2 deletions of the α-globin gene.

One α-globin deletion would not cause a microcytic anemia. Two deletions of the β-globin gene would cause beta-thalassemia major.
 

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i mite b wrong,bt i noticed a TEARDROP shaped r.b.c in THE SLIDE?:confused:characteristic of thalassemia....now,at age 17,a MALE can only present with a minor anemia...
cant b beta thalassemia,bcz a) 2 beta chain DELETION would produce major thalassemia n SYMPTOMATIC AT BIRTH
b)it has just 2 beta globin genes....nt 3....
c)one gene deletion of alpha gene is completely asymptomatic
so i would go for optoin D........
 

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i mite b wrong,bt i noticed a TEARDROP shaped r.b.c in THE SLIDE?:confused:characteristic of thalassemia....now,at age 17,a MALE can only present with a minor anemia...
cant b beta thalassemia,bcz a) 2 beta chain DELETION would produce major thalassemia n SYMPTOMATIC AT BIRTH
b)it has just 2 beta globin genes....nt 3....
c)one gene deletion of alpha gene is completely asymptomatic
so i would go for optoin D........
i think i screwed up,,,,its iron deficiency anemia ...:toosad:
 

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Guys m sorry didnt post the answer for this question.... was abit busy during these days...

The correct answer is D.
This patient has a hypochromic, microcytic anemia. Classically, the presence of HbA2 (α2δ2) suggests β-thalassemia minor. However, this is not one of the answer choices.

The learning point is that HbA2 is present in mild alpha-thalassemia - there's not enough of an alpha-chain deficiency to prevent the formation of HbA2. Hence, the correct answer is 2 deletions of the α-globin gene.

One α-globin deletion would not cause a microcytic anemia. Two deletions of the β-globin gene would cause beta-thalassemia major.
@usluipek
the correct answer is D.
 
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