Reversible amnesia in a Type 1 diabetic patient and bilateral hippocampal lesions on magnetic resonance imaging (MRI).
OBJECTIVE
Intensive insulin therapy of Type 1 diabetes limits its chronic complications, but is associated with an increased risk of severe hypoglycaemia and its neuroglycopenic consequences.


METHODS
Case report.


RESULTS
A 24-year-old male with 15 years' history of Type 1 diabetes, who was missing for 48 h, was found at home in ketoacidosis coma. Intensive care permitted a rapid improvement revealing an unexpected severe anterograde amnesia, confirmed by neuropsychological testing. MRI performed 4 days after admission showed abnormal bilateral hyperintensity signals on T2-weighted images in the hippocampus. Three months later, the patient had nearly completely recovered and resumed work. MR images and neuropsychological testing returned to normal.


CONCLUSIONS
The most likely course of events favours an initial prolonged hypoglycaemic coma following insulin overdose. The hippocampal injury may be a result of hypoglycaemia. Neuropsychological testing and MRI abnormalities were completely reversible. This case underlines the potential risks of intensive insulin therapy.
Holemans
X
X
Service de Médecine Interne, Centre Hospitalier Notre-Dame et Reine Fabiola, Charleroi, Belgium. xavier.holemans@chndrf.be
Dupuis
M
M
Misson
N
N
Vanderijst
J F
JF
D000328:Adult; D000647:Amnesia / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D003922:Diabetes Mellitus, Type 1 / Q000150:complications* / Q000188:drug therapy; D016883:Diabetic Ketoacidosis / Q000150:complications; D004569:Electroencephalography; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D007003:Hypoglycemia / Q000139:chemically induced / Q000150:complications; D007328:Insulin / Q000009:adverse effects; D007331:Insulin Coma / Q000150:complications; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D014057:Tomography, X-Ray Computed
D007328:Insulin