A case of insulinoma misidentified as schizophrenia due to its manifestation in neuropsychiatric symptoms

Insulinomas can present with neuroglycopenic symptoms suggesting neuropsychiatric disorders, delaying diagnosis and treatment. We recently treated a 65-year-old woman with insulinoma who was misdiagnosed at her nearby psychiatric clinic as having schizophrenia because of personality changes and memory impairment; she was treated with brexpiprazole, which was discontinued due to persistence of the symptoms. Despite her relatively low casual plasma glucose (70 mg/dL), the physician at the psychiatric clinic did not investigate the possibility of hypoglycemia, partly because her HbA1c level (5.2