“Please see this man with a 69-year history of hypoglycaemia”

Mutations in the HNF4A gene are associated with hyperinsulinaemic hypoglycaemia in infants, frequently evolving into relative deficiency of insulin in adulthood ­­­as maturity onset diabetes of the young (MODY). A 69-year-old male with a strong family history of adult-onset diabetes was referred with lifelong hypoglycaemia, found to be due to a pathogenic HNF4A mutation. HbA1c levels were low, continuous glucose monitoring demonstrated frequent low glucose events in the early morning, and he was successfully treated with diazoxide.