Convergence of infection, CAR-T therapy, and neuralgic amyotrophy: A case report.

Abstract: Neuralgic amyotrophy (NA) is a multifocal, immune-mediated inflammatory disorder of peripheral nerves and/or portions of the brachial plexus, typically presenting as regional pain followed by weakness. Awareness and recognition of this entity in the cancer population is important and relevant to physiatrists, given the frequency of immune system activation in this population, whether mediated by cancer, its treatments, or infections associated with an immunocompromised status. We present a case of NA presenting primarily as bilateral anterior interosseous mononeuropathies of onset following influenza infection (about one month prior) and chimeric antigen receptor T-cell (CAR-T) therapy (2-4 days prior). We discuss diagnostic challenges in NA and highlight key features of the history, physical examination, and electrodiagnostic findings that can yield clues to an underlying multifocal or immunologic process masquerading as a focal injury. Finally, we discuss the uncertain but plausible role of CAR-T therapy as a potential immunologic trigger for NA and invite further exploration.