slacker101

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Does anyone know where one could download the answers to the 2008 USMLE Step 1 release material. The link on the Kaplan website is not working. Thanks. Also could some please explain the answer to this question.

"Infant has episodes of hypoglycemia and sever lactic acidemia. His abdomen is protuberant, and he has several skin xanthomas on his upper and lower extremities. His also has elevated triglycerides, and a percutaneous liver biopsy reveals both fat and glycogen deposits. Which is most likely?
A) Glucose-6-phosphatase deficiency
B) Hepatic glycogen phosphorylase deficiency
C) Hyperlipidemia secondary to juvenile diabetes
D) Lipoprotein Lipase Deficiencey
E) Medium-Chain acy-CoA dehydrogenase deficiency
 

obiwan

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my guess would be von gierkes disease so choice A

wiki-test prep has explainations for the 150
 

docmd2010

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I'd also go with A. glycogen build up occuring because glucose can't get out into the blood stream, and elevated lipids because hsl is getting activating and mobilizing adipose. Von Gierke's is the likely diagnosis.
 

obiwan

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does anyone know why exactly there is lactic acidosis with von Gierkes?
 

InternationlDoc

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You can't reverse lactate --> pyruvate --> glucose (when going through gluconeogenesis) since your enzyme is missing. so lactic acid builds up due to lack of gluconeogenesis

thats what I'd reason. No source.
 

yohimbine1

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I would say buildup of pyruvate and lactate
 

DwyaneWade

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You can't reverse lactate --> pyruvate --> glucose (when going through gluconeogenesis) since your enzyme is missing. so lactic acid builds up due to lack of gluconeogenesis

thats what I'd reason. No source.
Right, the liver can't handle all the lactate coming from the rest of the body.