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Old 04-12-2007, 10:41 PM
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Question if any one can explain please

Why does a deficinecy in glucose-6-phosphatase cause gout??? If some can please explain this.

Also an increase in PRPP causes gout, i'm asuming this i because of an increase in purine production leading to gout is that rite?
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Old 04-13-2007, 12:54 AM
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Gout is characterized by high level or overproduction of uric acid, where sodium urate crystals deposit in joints of the extremities or interstitial tissue.

Overproduction can be considered in the metabolic defects of the de novo pathway, where an increase in the level of PRPP. Since there is a deficiency of glucose-6-phosphatase activity (von Gierke's disease), thus more glucose-6-phosphate are being shunt to the pentose phosphate pathway, leading to more ribose-5-phosphate... hence more PRPP.

More PRPP means increase glutamine-PRPP amidotransferase activity, which increase de novo pathway activity, leading to increase production of uric acid.

Last edited by Niacin_05; 04-13-2007 at 10:32 AM.
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Old 04-13-2007, 01:18 PM
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good answer B3.

Gout was diagonsed by hippocrates 2500 yrs ago as it existed among royal families. aka "king of diseases". im jus mentioning this so it might help remembering.

Dx - you cannot rely on hyperuricemia (high levels of uric acid in blood) to diagnose as person with gout could have low levels. also, a person may temporarily have high uric acid levels and not have gout. correct dx is often made by aspiration and put under microscopy for "monosodium urate crystals". Look for signs/sym of kidney failure cuz kidneys are unable to excrete the uric acid.

Rx - NSAIDS (aspirin)
acute attack - colchicine (given in 1800's to present). very effective, but after short term use causes side effects "Nausea, vommitting, Diarrhea". doses should also be lowered in pxt's with kidney diease.
long term: allopurinol.

ddx - while gout is commonly seen in males above 40, in a infant suspect HGPRT deficiency. "Lesch Nyhan syndrome" exhibit high level of uric acid (hyperuricemia) and will exhibit symptoms of gout and given the same rx. They might have vit. b12 deficiency so check for megaloblastic anemia.
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Old 04-15-2007, 11:06 AM
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good answer B3.
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