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Old 07-22-2012
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Biochemistry Increased Free Fatty Acids, No Ketones!

A 9-month-old girl is brought to the emergency department in a coma. Initial examination shows hepatomegaly and hypotonia. An analysis of blood samples shows elevated levels of muscle and liver enzymes and decreased levels of glucose. Samples taken after 24 hours of fasting show an increase in the level of free fatty acids, but no ketone bodies are detected. Fatty change is seen in liver and muscle biopsy specimens. What is the most likely cause of the disease?

a) carnitine deficiency
b) decrease in citrate production
c) decrease in malonyl CoA production
d) decrease in muscle phosphorylase
e) lipoprotein lipase deficiency
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Old 07-22-2012
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A...carnitine def-----hypoglycemia,hypoketonemia,increased FFA levels and lipid deposits in liver and muscle
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Old 07-22-2012
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Shouldn't it be med chain acetyl coA dehydrogenase (MCAD) deficiency

Carnitine acyl transferase def presents with muscle cramps/weakness, exercise intolerence and myoglobenuria
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Old 07-22-2012
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Quote:
Originally Posted by Rookie View Post
Shouldn't it be med chain acetyl coA dehydrogenase (MCAD) deficiency

Carnitine acyl transferase def presents with muscle cramps/weakness, exercise intolerence and myoglobenuria
there are various types of CAT def disorders---AD,AR x-linked....the symptoms u have listed belong to AR, the most common type.....
moreover,the features above in the question are not related to the other options..

http://en.wikipedia.org/wiki/Carniti..._II_deficiency
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Old 07-27-2012
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Default correct answer :)

yup, you are right guys it's A) carnitine deficiency

β-Oxidation of long-chain fatty acids occurs in the mitochondria matrix. Long-chain fatty acids must be transported across the mitochondrial inner membrane by L-carnitine. In carnitine shuttle defects, long-chain fatty acids accumulate in the cytoplasm, causing the fatty changes seen in biopsy specimens of muscle and liver. Tissues that use long-chain fatty acids as an energy source all must use glucose, which leads to hypoglycemia. Ketone bodies cannot be used for fuel because they are produced in mitochondria from acetyl CoA, which is the end product of β-oxidation of long-chain fatty acids.
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