...after fasting 8+ hrs in a 16 year old? since age 14 months, this girl has experienced recurrent episodes of profound fatigue (after fasting 8+ hours) associated with limpness, vomiting, and increased perspiration, which required hospitalization. she was unable to hold in any food and was rushed to the hospital, where glucose infusion was started intravenously. Her symptoms responded dramatically to this therapy. Initial serum glucose level was low (38 mg/dL), BUN slightly elevated (26mg/dL) as result of vomiting which led to dehydration, liver transaminase level in blood was slightly elevated (liver not palpably enlarged), free fatty acid levels in blood were elevated (but blood ketones below normal). Further testing showed elevated levels of several partially oxidized medium chain fatty acids (octanoic acid and 4-decenoic acid), increased metabolites of medium chain fatty acids containing 6-10 carbons (including medium chain acylcarnitine derivatives)

What deficiency would cause this? How common is it? Can mutations occur that cause this disorder? What could be impairing gluconeogenesis? How could it this deficiency be managed?