Paraneoplastic Lambert-Eaton myasthenic syndrome: a diagnostic challenge

BMJ Case Rep. 2023 Jan 27;16(1):e250947. doi: 10.1136/bcr-2022-250947.

Abstract

Lambert-Eaton myasthenic syndrome (LEMS) is a rare neuromuscular junction disorder. Underlying small cell lung cancer is found in more than half of patients. Proximal muscle weakness, autonomic features and areflexia are typical manifestations. However, LEMS is often misdiagnosed. We report a rare case of paraneoplastic LEMS, identified amid admission due to a different diagnosis. Our patient was initially admitted due to aspiration pneumonia. Further investigation revealed clinical and electrophysiological manifestations of LEMS. High clinical suspicion and early diagnostic workup were paramount in the patient outcome. Nevertheless, paraneoplastic aetiology was difficult to confirm and revealed itself a difficult challenge. Clinical awareness is crucial to diagnose LEMS and urge cancer screening and early treatment.

Keywords: Lung cancer (oncology); Neuromuscular disease.

Publication types

  • Case Reports

MeSH terms

  • Autoantibodies
  • Diagnosis, Differential
  • Humans
  • Lambert-Eaton Myasthenic Syndrome* / complications
  • Lambert-Eaton Myasthenic Syndrome* / diagnosis
  • Lung Neoplasms* / complications
  • Lung Neoplasms* / diagnosis
  • Small Cell Lung Carcinoma* / diagnosis

Substances

  • Autoantibodies