False positivity of anti aquaporin-4 antibodies in natalizumab-treated patients

Mult Scler. 2016 Aug;22(9):1231-4. doi: 10.1177/1352458516630823. Epub 2016 Feb 11.

Abstract

Background: Neuromyelitis optica spectrum disorders (NMOSD) represent a differential diagnosis of multiple sclerosis (MS). Detection of anti-aquaporin-4 antibodies (AQP4-Ab) is the strongest argument to confirm NMOSD. Diagnosing NMOSD is a major concern because specific MS disease modifying drugs can lead to neurological worsening.

Objective: To report the case of two natalizumab (NTZ) treated patients who presented a false positive result for AQP4-Ab.

Methods: A retrospective analysis of NTZ-treated patients who were tested positive for AQP4-Ab in our MS center.

Results: Two patients treated by NTZ presented a false positive result.

Conclusions: Clinicians should be aware of potential technical issues in detecting AQP4-Ab in NTZ-treated patients leading to false positive results.

Keywords: Multiple sclerosis; natalizumab; neuromyelitis optica.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Aquaporin 4 / immunology*
  • Autoantibodies / blood*
  • Autoimmunity*
  • Biomarkers / blood
  • False Positive Reactions
  • Female
  • Humans
  • Immunosuppressive Agents / adverse effects
  • Immunosuppressive Agents / therapeutic use*
  • Male
  • Multiple Sclerosis / blood
  • Multiple Sclerosis / diagnosis
  • Multiple Sclerosis / drug therapy*
  • Multiple Sclerosis / immunology
  • Natalizumab / adverse effects
  • Natalizumab / therapeutic use*
  • Predictive Value of Tests
  • Retrospective Studies
  • Serologic Tests*
  • Time Factors
  • Treatment Outcome
  • Young Adult

Substances

  • AQP4 protein, human
  • Aquaporin 4
  • Autoantibodies
  • Biomarkers
  • Immunosuppressive Agents
  • Natalizumab