Atypical motor neuron disease variant: facial-onset sensory and motor neuronopathy syndrome (FOSMN)

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Özenç B., Odabaşı Z., Tan E.

Egyptian Journal of Neurology, Psychiatry and Neurosurgery, vol.58, no.1, 2022 (ESCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 58 Issue: 1
  • Publication Date: 2022
  • Doi Number: 10.1186/s41983-022-00597-0
  • Journal Name: Egyptian Journal of Neurology, Psychiatry and Neurosurgery
  • Journal Indexes: Emerging Sources Citation Index (ESCI), Scopus, Academic Search Premier, Arab World Research Source, EMBASE, Directory of Open Access Journals
  • Keywords: FOSMN, Neuronopathy, Dysphagia, Motor neuron disease (MND)
  • Hacettepe University Affiliated: Yes


© 2022, The Author(s).Background: Facial-onset sensory and motor neuronopathy (FOSMN) is a rare disease whose cardinal features are initial asymmetrical facial sensory deficits slowly evolving and followed by bulbar symptoms and spreading of sensory and motor deficits from face to scalp, neck, and extremities. Case presentation: We described a 70-year-old man who presented with 6-month history of facial numbness on the left side, and gradual worsening of symptoms. Over several months, facial muscle weakness, dysarthria, and fasciculation had progressed. NCS, needle EMG and blink reflex responses suggested the diagnosis of FOSMN. The ganglioside panel (anti-GM1 and Gd1b) was positive. Considering the FOSMN autoimmune pathology hypothesis, IVIG treatment was given. Conclusion: In this case, we aimed to highlight the key clinical aspects of FOSMN and how to differentiate it from motor neuron disease and bring FOSMN to the attention of neurologists as a recently recognized and distinctive disorder.