Isolated Peripheral Nervous System Presentation in Ma/Ma2-Associated Autoimmunity

Andreu Vilaseca1,2, Macarena Villagrán-García3,4, Antonio Farina3,4

  • 1Center for Multiple Sclerosis and Autoimmune Neurology, Department of Neurology, Mayo Clinic College of Medicine, Rochester, MN.

Abstract

Insights

Ma/Ma2 antibodies rarely cause isolated peripheral nervous system (PNS) autoimmunity. This study found PNS syndromes like sensory neuronopathy in 3% of patients, often linked to cancer.

Area of Science:

  • Neurology
  • Immunology
  • Oncology

Background:

  • Ma/Ma2-associated neurologic autoimmunity typically affects the central nervous system (CNS).
  • Isolated peripheral nervous system (PNS) involvement is infrequently reported in Ma/Ma2 autoimmunity.

Purpose of the Study:

  • To determine the frequency of isolated PNS presentations in patients with Ma/Ma2 antibodies.
  • To describe the clinical syndromes associated with isolated PNS involvement in Ma/Ma2 autoimmunity.

Main Methods:

  • A nested case series design was employed within multicenter cohorts.
  • Patients with confirmed Ma/Ma2 antibodies (tissue-based assay and line-blot) and isolated PNS involvement were included.

Main Results:

  • Seven out of 212 patients (3%) exhibited isolated PNS involvement.
  • Reported PNS syndromes included sensory neuronopathy, myeloradiculopathy, radiculoplexopathy, motor neuronopathy, and multiple mononeuropathy.
  • Cancer was identified in 86% of affected patients, with various types including mesothelioma, lung, and breast cancer.

Conclusions:

  • Isolated PNS involvement is a rare but recognized manifestation of Ma/Ma2-associated autoimmunity.
  • Consider Ma/Ma2 antibody testing for patients presenting with neuronopathies and unexplained non-length-dependent neuropathies.

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