Postexercise reflex facilitation in Lambert-Eaton myasthenic syndrome

Pract Neurol. 2024 Jan 30:pn-2023-004032. doi: 10.1136/pn-2023-004032. Online ahead of print.

Abstract

A 62-year-old woman had 6 months of proximal weakness, fatigue and occasional diplopia, symptoms normally suggesting myasthenia gravis or inflammatory myopathy. Postexercise reflex facilitation is a bedside clinical sign that points to a diagnosis of the rarer alternative, Lambert-Eaton myasthenic syndrome (LEMS). We confirmed this diagnosis using electrodiagnostic short exercise testing and serum assay for voltage-gated calcium channel antibodies. Further investigation identified a small cell neuroendocrine carcinoma of the gallbladder, not previously associated with LEMS. Postexercise reflex facilitation is an important bedside clinical finding that helps clinicians to distinguish LEMS from its mimics.

Keywords: LAMBERT EATON SYNDROME; PARANEOPLASTIC SYNDROME.