Epileptic Seizure, Postictal Hemiparesis, and Hyperleukocytosis

Hyperleukocytosis-induced stroke and tonsillar herniation: Case report

Introduction

and Importance: Acute ischemic stroke is a rare event in children with leukemia, yet with long-term morbidity, substantial health, and economic cost. Central nervous system (CNS) leukemic involvement and chemotherapy-related stroke are the most common causes. Hyperleukocytosis induced stroke is very rarely reported.

Case presentation

A 2-year-old male child presented with hyperleukocytosis (leukocyte count was 320x10⁹/L). Bone marrow evaluation revealed T-cell acute lymphoblastic leukemia. He was treated with dexamethasone, vincristine and daunorubicin, and on day 4 of chemotherapy, he developed abnormal movements, altered mental status, limb weakness and mutism. Magnetic resonance imaging of the brain showed multifocal infarctions involving left pons and both cerebellar hemispheres causing tonsillar herniation with restricted diffusion and mild hydrocephalus but no leptomeningeal enhancement or leukemic infiltrates. Magnetic resonance angiography did not show any arterial stenosis. He was intubated, sedated and managed conservatively with dexamethasone. Cytologic analysis of cerebrospinal fluid showed no blasts. Thrombophilia work up was negative. Five weeks later, the patient had significant improvement in overall neurologic status. He is free of leukemia. MRI showed interval resolution of previous infarcts.

Clinical discussion

Hyperviscosity secondary to hyperleukocytosis was considered to be the most likely explanation for this patient stroke after excluding thrombophilia and leukemic infiltration. Prompt management with hydration and careful chemotherapy resulted in good outcome in our patient.

Conclusion

This case demonstrate the value of early recognition and prompt management of posterior circulation ischemic stroke in children with leukemia and hyperleukocytosis at presentation.

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Hyperleukocytosis and hyperviscosity can result in arterial ischemic stroke

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Posterior circulation ischemic strokes are very rare in children with leukemia

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Posterior circulation stroke can carries potential risk of herniation

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Prompt recognition and management are essential in posterior circulation stroke

MicroRNA Regulation of Oxidative Stress-Induced Cellular Senescence

Aging is a time-related process of functional deterioration at cellular, tissue, organelle, and organismal level that ultimately brings life to end. Cellular senescence, a state of permanent cell growth arrest in response to cellular stress, is believed to be the driver of the aging process and age-related disorders. The free radical theory of aging, referred to as oxidative stress (OS) theory below, is one of the most studied aging promoting mechanisms. In addition, genetics and epigenetics also play large roles in accelerating and/or delaying the onset of aging and aging-related diseases. Among various epigenetic events, microRNAs (miRNAs) turned out to be important players in controlling OS, aging, and cellular senescence. miRNAs can generate rapid and reversible responses and, therefore, are ideal players for mediating an adaptive response against stress through their capacity to fine-tune gene expression. However, the importance of miRNAs in regulating OS in the context of aging and cellular senescence is largely unknown. The purpose of our article is to highlight recent advancements in the regulatory role of miRNAs in OS-induced cellular senescence.