[Epileptic seizures in non-ketotic hyperglycemia]

Epileptic seizures during Non-Ketotic Hyperglycemia (NKH) in French Guiana: A retrospective study

INTRODUCTION

Epileptic seizures during non-ketotic hyperglycemia (NKH) represent a rare complication of uncontrolled diabetes mellitus. The definition associates a blood sugar level > 200mg/dL (11mmol/L), hyperosmolality, absence of ketosis, dehydration and seizure control after normalization of blood sugar levels.

MATERIAL AND METHODS

This retrospective observational study included patients hospitalized for epileptic seizures and NKH in the Cayenne Hospital Center between January 2010 and June 2020. The clinical, biological, and radiological results were collected.

RESULTS

18 out of 228 (7.9%) patients with both diabetes and epileptic seizures had NKH. The mean age of the 12 women and 6 men was 64.8 years. In 8 patients, brain imaging did not show acute lesions and the seizures disappeared with control of hyperglycemia by hydration and insulin. In 6 patients, the seizures revealed a stroke, hemorrhagic in 4 cases, ischemic in 2 cases. 4 patients had a seizure in a context of known vascular epilepsy. The epileptic seizures were mainly focal seizures with motor symptoms that could be repeated, focal to bilateral tonic-clonic or focal status.

CONCLUSION

Seizures in NKH are symptomatic of an acute brain lesion or vascular epilepsy more than 1 in 2 times. However, isolated NKH can cause seizures with a suggestive brain MRI.

Acute symptomatic seizures and systemic illness

PURPOSE OF REVIEW

This article addresses the occurrence of acute symptomatic seizures in the setting of many medical illnesses.

RECENT FINDINGS

Many medical illnesses can cause seizures. Metabolic derangements, such as disorders of serum glucose metabolism, cause seizures, as well as other neurologic manifestations. Many medicines (such as antibiotics, antivirals, antidepressants, and antipsychotics), whether used at typical doses or in overdosage, can lead to acute symptomatic seizures.

SUMMARY

Acute symptomatic seizures occur most often in illnesses that directly injure the brain. Trauma, stroke, CNS tumors, and CNS infection very commonly cause seizures. However, many medical illnesses do not directly injure the brain but lead to neurologic signs and symptoms, such as seizures. Recognizing these effects, especially in critically ill patients, is important for optimizing medical care.

Isolated aphasic status epilepticus as initial presentation of nonketotic hyperglycemia

Diagnosis of aphasic status epilepticus is sometimes not easy because of its rarity and electroclinical dissociation. Although most cases are associated with organic brain lesions, nonketotic hyperglycemia (NKH)-related aphasic status epilepticus is rare, especially if it is isolated (without other clinical seizure activity). On the other hand, unlike other metabolic disorders, or hypoglycemia-related generalized seizures, focal motor seizure and epilepsia partialis continua can occur in 25% of NKH, with seizures being the initial manifestation in up to 50% of patients. However, the presentation of epileptic aphasia is rare in NKH patients. We report a rare case of NKH presenting initially as persistent and isolated aphasic status epilepticus. Brain magnetic resonance imaging did not reveal any focal lesion, but ictal electroencephalography (EEG) disclosed left frontotemporal continuous theta to delta waves, intermingled with epileptiform discharges. Correcting the hyperglycemia failed to improve the language disorder, and the seizure was controlled only by the addition of carbamazepine. Patients with NKH may initially present with isolated aphasic status epilepticus. Unlike stroke-related aphasia, accurate diagnosis is difficult if based solely on neurologic examination and brain neuroimaging. Use of EEG and blood sugar determination should be helpful in this special condition.

[Partial visual seizures induced by non-ketosic hyperglycemia: magnetic resonance imaging and visual evoked potential descriptions. A study of two cases reports with radiologic and electrophysiologic abnormalities]

INTRODUCTION

Non-ketosic hyperglycemia (NKH) may increase the likelihood of focal epileptic seizures, including commonly motor expression; rarely, they can have a visual expression.

METHODS

The authors describe the observation of two men, who were hospitalized for visual manifestations; with episodes of homonymous hemianopia and hallucinations, revealing occipital seizure, secondary to NKH. Clinical data and characteristics of the investigations, including radiological imaging (MRI) and electrophysiological results of visual evoked potentials (VEP) are specified.

RESULTS

MRI showed transitory low signal on T2 and FLAIR in occipital areas. Spectro-MR identified a moderate diminution of the NAA and lipids spikes, compatible with laminar necrosis. VEP revealed a transient decrease of the P100 amplitude.

DISCUSSION

These two observations underline the existence of acute symptomatic seizures with a visual starting point which is often indicative of diabetes. Through these observations with a review of 28 patients from the literature, MR imaging characteristics and possible anomalies collected on VEP are discussed. Such seizures are resistant to anticonvulsant treatment and respond best to insulin and rehydration.

CONCLUSION

The visual manifestations indicative of seizures with an occipital starting point in the context of NKH are possible enabling rapid initiation of effective symptomatic treatment with insulin.

Fructose-1,6-bisphosphate has anticonvulsant activity in models of acute seizures in adult rats

A variety of observations suggest that decreasing glycolysis and increasing levels of reduced glutathione, generated by metabolism of glucose through the pentose phosphate pathway, would have an anticonvulsant effect. Because fructose-1,6-bisphosphate (F1,6BP) shifts the metabolism of glucose from glycolysis to the pentose phosphate pathway, it was hypothesized to have anticonvulsant activity. The anticonvulsant activity of F1,6BP was determined in rat models of acute seizures induced by pilocarpine, kainic acid, or pentylenetetrazole. The efficacy of F1,6BP was compared with that of 2-deoxyglucose (2-DG; an inhibitor of glucose uptake and glycolysis), valproic acid (VPA), and the ketogenic diet. One hour before each convulsant, Sprague Dawley rats received either saline (as seizure controls), F1,6BP (0.25, 0.5 or 1 g/kg), 2-DG (0.25 or 0.5 g/kg), or VPA (0.3 g/kg). Additional animals received the ketogenic diet (starting at 20 or 60 d old). Time to seizure onset, seizure duration, and seizure score were measured in each group. F1,6BP had dose-dependent anticonvulsant activity in all three models, whereas VPA had partial efficacy. 2-DG was only effective in the pilocarpine model. The ketogenic diet had no effect in these models. F1,6BP was also partially effective when given at the first behavioral seizure after pilocarpine. Administration of sodium lactate, which bypasses the block in the glycolytic pathway, abolished the anticonvulsant activity of 2-DG in the pilocarpine model, but only decreased the efficacy of F1,6BP. These data demonstrate that F1,6BP has significant anticonvulsant efficacy.

Cerebellar leptomeningeal carcinomatosis in a dog

Diffuse cerebellar meningeal carcinomatosis secondary to haematogenous dissemination from an anaplastic solid mammary carcinoma was diagnosed in an old German shepherd dog suffering from seizures and rapidly progressing to stupor. A single computed tomography cerebellar scan identified an unusual homogeneous density area that was considered to be associated with a vascular disorder, in the absence of space-occupying lesions. At necropsy, nodular masses were observed in the mammary gland, lungs, tracheobronchial lymph nodes and adrenals. Cerebellar leptomeninges were affected by diffuse blood effusion. Histology showed a solid mammary tumour, characterised by anaplastic cells with a cytoplasmic keratin-positive and vimentin-negative immunoreaction. The tumour had spread to the lungs, tracheobronchial lymph nodes and adrenals. Cerebellar leptomeninges were diffusely infiltrated by the cytokeratin-positive neoplastic cells. Even though computed tomography scan gave no evidence of meningeal carcinomatosis, it was considered that a cerebellar vascular disorder might be present. This was subsequently confirmed by neuropathological investigation and seen to be associated with a cerebellar leptomeningeal carcinomatosis.

Focal neuronal loss, reversible subcortical focal T2 hypointensity in seizures with a nonketotic hyperglycemic hyperosmolar state

INTRODUCTION

Neuroimaging in seizures associated with nonketotic hyperglycemia (NKH) is considered normal. We report magnetic resonance imaging (MRI) abnormalities in four patients with NKH and seizures.

METHODS

We prospectively evaluated clinical and radiological abnormalities in four patients with NKH during the period March 2004 to December 2005.

RESULTS

All patients presented with seizures, either simple or complex partial seizures or epilepsia partialis continua. Two of them had transient hemianopia. MRI showed subcortical T2 hypointensity in the occipital white matter and in or around the central sulcus (two patients each), T2 hyperintensity of the overlying cortex (two patients), focal overlying cortical enhancement (three patients) and bilateral striatal hyperintensity (one patient). Diffusion-weighted imaging (DWI) performed in three patients showed restricted diffusion. The ictal semiology and electroencephalographic (EEG) findings correlated with the MRI abnormalities. On clinical recovery, the subcortical T2 hypointensity and striatal hyperintensity reversed in all patients. The initial cortical change evolved to FLAIR hyperintensity suggestive of focal cortical gliosis. The radiological differential diagnosis considered initially included encephalitis, malignancy and hemorrhagic infarct rendering a diagnostic dilemma.

CONCLUSION

We identified subcortical T2 hypointensity rather than hyperintensity as a characteristic feature of seizures associated with NKH. Only very few similar reports exist in literature. Reversible bilateral striatal T2 hyperintensity in NKH has not been reported to the best of our knowledge.

Crises épileptiques révélatrices d’une hyperglycémie sans cétose

In patients older than 50 years, a first seizure can reveal non-ketotic hyperglycemia, regardless of any previous history of diabetes mellitus. Partial motor seizures are observed in most cases, sometimes with epilepsia partialis continua. Plasma glucose levels are usually above 20 mmol/L, and serum osmolarity is normal or slightly elevated. The absence of ketoacidosis may promote the occurrence of seizures. EEG and neuroimaging between seizures are usually normal. Treatment involves correction of the hyperglycemia with insulin treatment and rehydration.