Progressive encephalomyelitis with rigidity and myoclonus: a syndrome with diverse clinical features and antibody responses

Eur Neurol. 2013;69(5):257-62. doi: 10.1159/000342237. Epub 2013 Feb 20.

Abstract

Background/aims: To better characterize progressive encephalomyelitis with rigidity and myoclonus (PERM) syndrome and identify novel PERM phenotypes.

Methods: The clinical features and antibody status of PERM patients were investigated using immunoblots, cell-based assays, RIA, protein macroarray and ELISA.

Results: Two patients with supratentorial involvement showed abnormal PET or EEG findings. One patient was discovered to have renal cell carcinoma, and protein macroarray revealed Ma3-antibodies. Another patient with leucine-rich, glioma-inactivated 1 (LGI1) and glutamic acid decarboxylase (GAD) antibodies showed a good response to immunotherapy.

Conclusion: The heterogeneity of the immunological features suggests that PERM is caused by diverse pathogenic mechanisms. Seropositivity to well-characterized neuronal cell surface antigens might indicate a good treatment response.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Autoantibodies / blood*
  • Encephalomyelitis / blood*
  • Encephalomyelitis / complications*
  • Encephalomyelitis / drug therapy
  • Enzyme-Linked Immunosorbent Assay
  • Glutamate Decarboxylase / immunology
  • HEK293 Cells
  • Humans
  • Immunosuppressive Agents / therapeutic use
  • Intracellular Signaling Peptides and Proteins
  • Ion Channels / immunology
  • Male
  • Membrane Proteins / immunology
  • Middle Aged
  • Muscle Rigidity / blood*
  • Muscle Rigidity / complications*
  • Muscle Rigidity / drug therapy
  • Myoclonus / blood*
  • Myoclonus / complications*
  • Myoclonus / therapy
  • Nerve Tissue Proteins / immunology
  • Protein Array Analysis
  • Proteins / immunology
  • Transfection

Substances

  • Autoantibodies
  • CNTNAP2 protein, human
  • Immunosuppressive Agents
  • Intracellular Signaling Peptides and Proteins
  • Ion Channels
  • LGI1 protein, human
  • Membrane Proteins
  • Nerve Tissue Proteins
  • Proteins
  • Glutamate Decarboxylase

Supplementary concepts

  • Progressive Encephalomyelitis with Rigidity