Isolated insular stroke: topography is the answer with respect to outcome and cardiac involvement

Background and purpose

Isolated insular strokes (IIS) are a rare occurrence due to the frequent concomitant involvement of adjacent territories, supplied by the M2 segment of the middle cerebral artery (MCA), and clinical aspects are sometimes contradictory. We aimed to describe clinical and radiological characteristics of a pure IIS case series, focusing on its functional outcome and cardiac involvement.

Methods

We identified 15 isolated insular ischemic strokes from a pool of 563 ischemic strokes occurred between January 2020 and December 2021. Data collection consisted of demographic and baseline clinical characteristics, comorbidities, electrocardiograms, echocardiograms, stroke topography and etiology, reperfusive treatments, and outcome measures. Descriptive statistical analysis was carried out.

Results

Newly detected cardiovascular alterations were the prevalent atypical presentation. Cardioembolism was the most frequent etiology. Most of patients had major neurological improvement at discharge and good outcome at 3-months follow-up.

Discussion and conclusion

IIS are extremely rare, representing according to our study about 2.6% ischemic strokes cases per year, and patients have peculiar clinical manifestations, such as dysautonomia and awareness deficits. Our data suggest the possibility for these patients to completely recover after acute ischemic stroke notwithstanding the pivotal role of the insula in cerebral connections and the frequent association with MCA occlusion. Moreover, given the central role of the insula in regulating autonomic functions, newly detected cardiac arrhythmias must be taken into consideration, as well as a full diagnostic work-up for the research of cardioembolic sources. To our knowledge, this is the largest monocentric case series of IIS and it might be useful for future systematic reviews.

The Possible Precipitating Role of SARS-CoV-2 in a Case of Late-Onset Hemichorea Due to a Hyperosmolar Hyperglycemic State: Case Report and Brief Literature Review

Case report: An 83-year-old Italian female developed postural instability and gait disturbance associated with a concomitant hyperosmolar hyperglycemic state. Brain CT and MRI scans detected a lesion in the right putamen due to metabolic derangement. A month later, the patient started suffering from choreic movements along the left side of the body with brachio-crural distribution, approximately three weeks after SARS-CoV-2 infection. She was treated with tetrabenazine with complete resolution of the aberrant movements. Any attempt to reduce tetrabenazine caused a relapse of the symptoms. Discussion: In diabetic patients, choreic syndrome should be considered a rare event with a benign prognosis and favorable response to treatment. It is the result of a condition known as "diabetic striatopathy". The association of new-onset choreic movements, an episode of hyperglycemia, and a basal ganglia lesion is suggestive of this condition. Its pathophysiology remains unclear, and a lot of hypotheses are still debated. SARS-CoV-2 might have played a role in triggering the patient's motor symptoms. Conclusions: Our case report agrees with the general features of those reported in the literature about movement disorders in diabetic patients. The late onset of symptoms and the poor response to treatment seem to be atypical characteristics of the syndrome. Although speculative, we cannot exclude the role of SARS-CoV-2. This case can be added to the literature for further studies and reviews.

A State-of-Art Review of the Vicious Circle of Sleep Disorders, Diabetes and Neurodegeneration Involving Metabolism and Microbiota Alterations

In the context of neurodegenerative disorders, cognitive decline is frequently reported in older population. Recently, numerous metabolic pathways have been implicated in neurodegeneration, including signaling disruption of insulin and other glucose-regulating hormones. In fact, Alzheimer's disease has now been considered as "type-3 diabetes". In this review, we tried to clarify the role of sleep impairment as the third major player in the complex relationship between metabolic and neurodegenerative diseases. Altered sleep may trigger or perpetuate these vicious mechanisms, leading to the development of both dementia and type 2 diabetes mellitus. Finally, we analyzed these reciprocal interactions considering the emerging role of the gut microbiota in modulating the same processes. Conditions of dysbiosis have been linked to circadian rhythm disruption, metabolic alterations, and release of neurotoxic products, all contributing to neurodegeneration. In a future prospective, gut microbiota could provide a major contribution in explaining the tangled relationship between sleep disorders, dementia and diabetes.