Focal epileptic seizure induced by transient hypoglycaemia in insulin‐treated diabetes

Abstract

Hypoglycaemia, common in diabetic patients treated with insulin, can induce various neurological disturbances. Of these, seizures are the most common acute symptom, mainly of the generalised tonic-clonic type, with focal events only exceptionally being reported and documented. Hypoglycaemia can modify cortical excitability by determining an imbalance between excitation and inhibition; some brain structures, such as the temporal lobe and hippocampus, appear to be particularly susceptible to this insult. We describe a case of a 61-year-old diabetic patient in whom insulin-induced transient hypoglycaemia triggered a focal seizure of temporal origin that was well documented by EEG during 24-hour ambulatory monitoring. This is, to our knowledge, one of the few, well-documented cases of this type of seizure.

Hypoglycemia-induced alterations in hippocampal intrinsic rhythms: Decreased inhibition, increased excitation, seizures and spreading depression

“…The anterior temporal lobe and hippocampus are among the most epileptogenic areas of the brain and have been implicated as possible trigger zones for hypoglycemic seizures (Baloyannis et al, 1987;Gibbs and Murray, 1954;Lapenta et al, 2010), although in vivo EEG recordings have not clearly established the areas of seizure origin (Del Campo et al, 2009;Gibbs and Murray, 1954;Velisek et al, 2008). It is clear that severe hypoglycemia can lead to neuronal death predominantly in the hippocampus and in the superficial layers (layers II-III) of the occipital and parietal cortices, and striatum (Auer, 2004;Auer et al, 1985a;Auer et al, 1985b;Bree et al, 2009).…”

Severe Hypoglycemia in a Juvenile Diabetic Rat Model: Presence and Severity of Seizures Are Associated with Mortality

“…Hypoglycemia is the major limiting factor in the management of Type 1 diabetes [5]–[8] with patients experiencing an average of 2 episodes per week [9]. More severely, hypoglycemia can lead to seizures and coma, with generalized seizures being the major acute complication [10] occurring in children [11] and adolescents [12]. In addition, devastating effects, such as the “dead in bed” syndrome, possibly due to hypoglycemic seizures [13], occur approximately 3 times more frequently in young people with diabetes than in those without [14].…”

Hypoglycemic seizures and epilepsy in type I diabetes mellitus

“…Although many hypoglycemic seizures are generalized tonic-clonic, some studies, in which hypoglycemic seizures had been recorded, suggest that they arise in the temporal lobe and have secondary generalization [9]. This may have happened in our patients, as suggested by seizure semiology and EEG performed in the first 24 h.…”