Why would a young child not be able to break down fatty acids during a long period of fasting?
During fasting, the body should be able to break down fatty acids to form ketone bodies. Children do not store glucose as well as adults, and so they begin to depend on the creation of ketone bodies much faster.
The process of breaking down fatty acids to form ketone bodies is called beta-oxidation. When this process is impaired, the body will become severely hypoglycemic.
Primary carnitine deficiency is when the body is not able to process fats into energy. This often appears during infancy or childhood and the symptoms include encephalopathy, confusion, vomiting, weakness, hypoglycemia or an enlarged heart – which is is seen in cardiomyopathy.
The most commonly deficient enzyme in the beta-oxidation pathway is acyl-CoA dehydrogenase. This enzyme is essential for the first step in the beta-oxidation pathway. If it is not present, medium-chain fatty acids cannot be broken down into acetyl-CoA.
To prevent these severe hypoglycemic episodes, children with this deficiency should eat regularly with foods that are low in fat, but high in carbohydrates.