Mittal, Shivam Om

AbstractParaneoplastic neurological syndrome (PNS) comprises a group of neurological disorders that result from a misguided immune response to the nervous system triggered by a distant tumor. These disorders frequently manifest before the diagnosis of the underlying neoplasm. Since the first reported case in 1888 by Oppenheim, the knowledge in this area has evolved rapidly. Several classic PNS have been described, such as limbic encephalitis, paraneoplastic cerebellar degeneration, encephalomyelitis, opsoclonus-myoclonus, sensory neuronopathy, Lambert-Eaton Myasthenic syndrome, and chronic gastrointestinal dysmotility. It is now recognized that PNS can have varied nonclassical manifestations that extend beyond the traditional syndromic descriptions. Multiple onconeural antibodies with high specificity for certain tumor types and neurological phenotypes have been discovered over the past 3 decades. Increasing use of immune checkpoint inhibitors (ICIs) has led to increased recognition of neurologic ICI-related adverse events. Some of these resemble PNS. In this article, we review the clinical, oncologic, and immunopathogenic associations of PNS.

Background: Restless Legs Syndrome (RLS) is a common movement disorder with an estimated prevalence of up to 12%. Previous small studies with onabotulinumtoxin A (OnaA) for RLS have shown inconsistent results. Methods: Twenty-four patients with an International RLS score (IRLS) of >11 (moderate-severe) were enrolled in this blinded, placebo-controlled crossover study. Twenty-one patients completed the evaluations at 4, 6, and 8 weeks after each injection. One-hundred units of Incobotulinumtoxin A (IncoA) or normal saline were injected into tibialis anterior, gastrocnemius, and biceps femoris muscles each side. Results: Improvement from a severe (IRLS >21) to a mild/moderate (IRLS ≤20) score was significant at four weeks (p = 0.0036) and six weeks (p = 0.0325) following IncoA administration compared to placebo. Additionally, there was significant improvement in pain score at six weeks as measured by Visual Analogue Scale (p = 0.04) and the Johns Hopkins Quality of Life Questionnaire (p = 0.01) in the IncoA group. Definite or marked improvement on Patient Global Impression of Change was seen in 7 out of 21 patients in the IncoA group vs. 1 out of 21 patients in the placebo group at 4 weeks (p = 0.012). Conclusion: IncoA injection lead to a reduction in severity of RLS symptoms, pain score, and quality of life, without any adverse effects.

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