Dados do Trabalho

Título

A case of epilepsy investigation with incidental postmortem finding of an insulinoma

Apresentação do caso

A 21-year-old male was referred to our hospital to investigate episodes of loss of contact with surroundings, confusion with dizziness, headaches, and somnolence. Most of the symptoms occurred at night, with sudoresis, tachycardia, and feelings of fear. Occasionally, he collapsed on the floor with his body shaking, while he might shout out sentences and feel hungry afterwards. Such episodes started at the age of 13, and remitted after 2 years with phenytoin that was then discontinued. He remained asymptomatic until 19 years old, when the episodes resumed. Electroencephalogram (EEG) was normal in two instances, with left frontotemporal sharp waves in one instance, and then systematically right sided in more than fifteen other EEGs. MRI was normal at 37, 44, and 52 years old. PET-CT at 52 years old showed diffuse hypocaptation in the right frontotemporal area. Meanwhile, his episodes were increasingly worse, notwithstanding several treatment strategies using a combination of antiepileptic drugs. In more than 30 years of investigation his measured serum glucose levels varied from 83 to 105 mg/dL, with no hypoglycemic episodes during video-EEG monitoring. He went to anterior temporal lobectomy at the age of 55, with neuropathological findings suggestive of a mild malformation of cortical development. Five days after surgery, he went home with no seizures. Five days after discharge, he returned to our hospital in cardiac arrest, and died. At necropsy, the cause of death was established as pulmonary hemorrhagic infarction, and an insulinoma was found.

Discussão

We described a case with two diagnoses which disclose analogous symptomatology. Concomitant epilepsy and pancreatic tumor are exceedingly rare, with only two case reports in the literature. Insulinoma is a tumor with a reported incidence of 0.5-5 per million person-years. In insulinoma case series, 16-39% had been misdiagnosed as epilepsy, and proper diagnosis may take decades. Such patients may exhibit epileptiform EEG patterns and long-term brain abnormalities, but they present with significant hypoglycemia during the seizure episodes, which was never documented in our patient.

Comentários finais

As found in the current case, it is debatable if the finding of an incidental insulinoma was an important contributor to the patient’s symptoms. Given that glucose serum levels alone are not able to discard or confirm insulinoma diagnosis, pharmacoresistant cases with unusual symptomatology should raise suspicion of a neuroendocrine tumor.