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Hemolytic anemia & sulfas

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genetics-
5K views 12 replies 8 participants last post by  tinhi 
#1 ·
A 5-year-old Egyptian boy receives a sulfonamide antibiotic as prophylaxis for recurrent urinary tract infections. Although he was previously healthy and well-nourished, he becomes progressively ill and presents to your office with pallor and irritability. A blood count shows that he is severely anemic with jaundice due to hemolysis of red blood cells. Which of the following would be the simplest test for diagnosis?

a. Northern blotting of red blood cell mRNA
b. Enzyme assay of red blood cell hemolysate
c. Western blotting of red blood cell hemolysates
d. Amplification of red blood cell DNA and hybridization with allele-specific oligonucleotides (PCR-ASOs)
e. Southern blot analysis for gene deletions
 
#3 ·
The "easiest" part of this question stem is making this a bit difficult because I'm by no means a lab expert.

I'm between A and B because I think both can detect a G6PD deficiency. As for which one is easier, I'll go with the more commonly used test which is a northern blot. Enzyme assay seems like it might be complicated but then again, I'm not really sure how they are done.

So I'd guess A :eek:
 
#5 ·
The "easiest" part of this question stem is making this a bit difficult because I'm by no means a lab expert.

I'm between A and B because I think both can detect a G6PD deficiency. As for which one is easier, I'll go with the more commonly used test which is a northern blot. Enzyme assay seems like it might be complicated but then again, I'm not really sure how they are done.

So I'd guess A :eek:
So after taking a second look at this question, i realized that RBC's dont have any DNA left so there is no mRNA to detect! :rolleyes: Only answer choices B and C make sense knowing that RBC's no longer have nucleus/DNA

I'd go with B
 
#9 ·
correct answer

The answer is b.

Red cell hemolysis after drug exposure suggests a red cell enzyme defect, most easily confirmed by enzyme assay to demonstrate deficient activity. A likely diagnosis here is glucose-6-phosphate dehydrogenase (G6PD) deficiency.
DNA analysis is available to demonstrate particular alleles, but simple enzyme assay is sufficient for diagnosis.
 
#10 ·
The answer is b.

Red cell hemolysis after drug exposure suggests a red cell enzyme defect, most easily confirmed by enzyme assay to demonstrate deficient activity. A likely diagnosis here is glucose-6-phosphate dehydrogenase (G6PD) deficiency.
DNA analysis is available to demonstrate particular alleles, but simple enzyme assay is sufficient for diagnosis.
just to make sure :the DNA analysis needs a bone marrow sample???
coz its gonna be from blastocytes right??
 
#12 ·
Nice one,
For this I looked at answer options b4 looking at question.
Looking at question, immediately see G6PD and know that cause of that is enzyme related so know dx is based on B
 
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