Acute Flaccid Myelitis With Neuroradiological Finding of Brachial Plexus Swelling

Pediatr Neurol. 2020 Aug:109:85-88. doi: 10.1016/j.pediatrneurol.2020.04.004. Epub 2020 Apr 13.

Abstract

Background: Acute flaccid myelitis is a recently defined clinically distinct syndrome of polio-like acute flaccid paralysis. Acute flaccid myelitis cases show characteristic neuroradiological features of longitudinal spinal cord lesions with predominant gray matter involvement. Current evidence suggests injury to the anterior horn neurons as the underlying mechanism.

Methods: We describe three patients with acute flaccid myelitis who developed flaccid upper limb weakness with diminished deep tendon reflexes after prodromal fever. Spinal magnetic resonance imaging (MRI) (axial and sagittal T1- and T2-weighted sequences) and brachial plexus MRI (coronal short tau inversion recovery sequence) at the acute stage were performed.

Results: Spinal MRI showed extensive longitudinal lesion in the spinal cord with predominant gray matter involvement. We were able to demonstrate concurrent swelling and hyperintensity in the brachial plexus in all the three patients at the acute stage.

Conclusion: The coexisting signal intensities suggest an extension of acute flaccid myelitis pathology to the brachial plexus, highlighting the possible peripheral nerve involvement in acute flaccid myelitis.

Keywords: Acute flaccid myelitis; Brachial plexus swelling; MR neurography; Peripheral nerve; STIR.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Brachial Plexus / diagnostic imaging
  • Brachial Plexus / pathology*
  • Brachial Plexus / physiopathology
  • Central Nervous System Viral Diseases / diagnostic imaging
  • Central Nervous System Viral Diseases / pathology*
  • Central Nervous System Viral Diseases / physiopathology
  • Child, Preschool
  • Female
  • Gray Matter / diagnostic imaging
  • Gray Matter / pathology*
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Myelitis / diagnostic imaging
  • Myelitis / pathology*
  • Myelitis / physiopathology
  • Neuromuscular Diseases / diagnostic imaging
  • Neuromuscular Diseases / pathology*
  • Neuromuscular Diseases / physiopathology
  • Spinal Cord / diagnostic imaging
  • Spinal Cord / pathology*

Supplementary concepts

  • acute flaccid myelitis