Autoimmune nodopathy with anti-contactin 1 antibody characterized by cerebellar dysarthria: a case report and literature review

Front Immunol. 2024 Mar 8:15:1308068. doi: 10.3389/fimmu.2024.1308068. eCollection 2024.

Abstract

Background: Autoimmune nodopathy (AN) has emerged as a novel diagnostic category that is pathologically different from classic chronic inflammatory demyelinating polyneuropathy. Clinical manifestations of AN include sensory or motor neuropathies, sensory ataxia, tremor, and cranial nerve involvement. AN with a serum-positive contactin-1 (CNTN1) antibody usually results in peripheral nerve demyelination. In this study, we reported a rare case of AN with CNTN1 antibodies characterized by the presence of CNTN1 antibodies in both serum and cerebrospinal fluid, which is associated with cerebellar dysarthria.

Methods: A 25-year-old man was admitted to our hospital due to progressive dysarthria with limb tremors. The patient was initially diagnosed with peripheral neuropathy at a local hospital. Three years after onset, he was admitted to our hospital due to dysarthria, apparent limb tremor, and limb weakness. At that time, he was diagnosed with spinocerebellar ataxia. Eight years post-onset, during his second admission, his condition had notably deteriorated. His dysarthria had evolved to typical distinctive cerebellar characteristics, such as tremor, loud voice, stress, and interrupted articulation. Additionally, he experienced further progression in limb weakness and developed muscle atrophy in the distal limbs. Magnetic resonance imaging (MRI), nerve conduction studies (NCS), and autoimmune antibody tests were performed.

Results: The results of the NCS suggested severe demyelination and even axonal damage to the peripheral nerves. MRI scans revealed diffuse thickening of bilateral cervical nerve roots, lumbosacral nerve roots, cauda equina nerve, and multiple intercostal nerve root sheath cysts. Furthermore, anti-CNTN1 antibody titers were 1:10 in the cerebrospinal fluid (CSF) and 1:100 in the serum. After one round of rituximab treatment, the patient showed significant improvement in limb weakness and dysarthria, and the CSF antibodies turned negative.

Conclusion: Apart from peripheral neuropathies, cerebellar dysarthria (central nervous system involvement) should not be ignored in AN patients with CNTN1 antibodies.

Keywords: autoimmune nodopathy; cerebellar dysarthria; contactin-1; magnetic resonance imaging; nerve conduction studies.

Publication types

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

MeSH terms

  • Adult
  • Ataxia
  • Contactin 1
  • Dysarthria* / complications
  • Humans
  • Male
  • Polyradiculoneuropathy, Chronic Inflammatory Demyelinating*
  • Tremor / complications

Substances

  • Contactin 1

Grants and funding

The author(s) declare that financial support was received for the research, authorship, and/or publication of this article. This work was supported by the Leading Medical Talents in Yunnan Province (L-2017013); Yunnan Ten Thousand Talents Program - Yunling Famous Doctors (YNWR-MY-2018-018); Basic Research Project of Yunnan Province General Project (202101AT070235, 202401CF070010); Basic Research Program of Yunnan Province (Special Project of Kunming Medical Association)(202101AY070001-245); National Natural Science Foundation for Youths of China (Grant No. 82301534); The First People's Hospital of Yunnan Province High-Level Talent Subsidy Program (2023-KHRCBZ-B17).