Early-onset symptomatic hypoglycemia in infancy,
commonly presenting as seizures, disorientation, abnormal eye movements,
and/or coma occurring in the morning before breakfast or after inadvertent
fasting. Mild forms may display less suggestive signs, such as drowsiness,
lethargy, mental confusion, sweating, pallor, attention deficit, and
headache. Evolution is characterized by growth retardation. Physical
examination may reveal mild hepatomegaly.