Severe hypoglycemic encephalopathy due to hypoallergenic formula in an infant.

A 7-month-old girl was brought to hospital due to vomiting. Upon admission, she was in a convulsive state and stupor with extremely low blood glucose. Head computed tomography showed brain edema, and comprehensive treatment for acute encephalopathy was initiated immediately. Severe hypoglycemia, metabolic acidosis, elevation of ammonia and serum transaminases and creatine kinase suggested metabolic decompensation. Infusion of a high-glucose solution containing vitamins, biotin, and l-carnitine resolved the metabolic crisis quickly, but brain damage was irreversible. She was found to have been fed exclusively on a hypoallergenic formula (HF) for 7 months, although she was found later to be non-allergic. Evidence of inborn metabolic diseases was absent, therefore biotin deficiency and carnitine deficiency were concluded to be a consequence of reliance on a HF for a prolonged period. Health-care professionals should warn parents of the consequences of using HF.