enzyme deficiency!

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enzyme deficiency!

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edie
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08/28/07 - 11:45 PM

When exercising, a 19 year old man develops painful cramps that are associated with acute episodes of myoglobinuria. Administration of oral glucose during the acute episode does not alleviate the symptoms. Additional studies show that a hemolytic anemia is present. The patient most likely suffers from a deficiency of which enzyme?

a- branching enzyme
b- muscle phosphorylasee
c- glucose 6 phosphatase
d-liver phosphorylase
e- phosphofructokinase

keepgoing
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08/29/07 - 12:22 AM

b.mcardle's dis

hope4dabest
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08/29/07 - 12:32 AM

E....

sunny811
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08/29/07 - 03:31 AM

i think its B mcardle's

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shumaila
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08/29/07 - 10:05 AM

c???

shumaila
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08/29/07 - 10:07 AM

may be B? but what abt hemolytic anemia then?

keepgoing
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08/29/07 - 10:43 AM

hey edie..it seems tricky question b/c anyone can pick mcardle swith above symptoms, i juz observed a to d all glycogen storage dis and only e option is which is the glycolysis level...do u mean we have e as asnwer raised eyebrow

mcc cause of hemolytic anemia on enzyme defi are 2..G6PD or PK.

edie
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08/29/07 - 11:02 AM

And the winner is... Hope4daBest! It's E. Check it:

Phosphofructokinase deficiency is one of the glycogen storage diseases. There is a congenital deficiency of an enzyme responsible for the breakdown of glycogen to glucose. It is classified as glycogen storage disease (GSD) type VII. It is also called Tarui's disease.

The enzyme deficiency results in the accumulation of glycogen in the tissues. There may be systemic consequences or there may be a limited number of tissues that are affected. Phosphofructokinase catalyzes the rate-limiting step in glycolysis. This is fructose-1-phosphate to fructose-1,6-diphosphate. Deficiency causes muscle pain and fatigue and weakness with exercise. It resolves with rest, but there is no specific treatment. It does not always progress to severe disability.

Sorry for taking so long to get back to this guys smiling face

edie
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08/29/07 - 11:04 AM

And Keep Going gets the prize, too nod

keepgoing
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08/29/07 - 11:07 AM

#10

hi edie thanks alot..i didnt do this type VII glycogen dis shocked

..anyways but dont u think this deficiency wud produce s/s at rest also(on general glycolysis) not only on exercising and severe form??well thanks i will google now but if u have to add plzz do..tc

keepgoing
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08/29/07 - 11:07 AM

#11

edie wrote:
And Keep Going gets the prize, too nod

thanks

medocuk
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08/29/07 - 11:09 AM

#12

I will go for glucose 6 phosphate deficiency solely on the strenght of hemolytic anemias and the other 2 features viz cramping after excercise and myogobinuria can be seen in McArdles and G6PD deficiency.

medocuk
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08/29/07 - 11:11 AM

#13

Oh man I have to go read some more. Thanks for the answer I haven't registered Tauri's disease yet. sad

hope4dabest
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08/29/07 - 12:36 PM

#14

...

SmokyWaters
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09/23/07 - 05:39 AM

#15

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