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Updated: May 30, 2026
09:29
Induction of Paralysis and Visual System Injury in Mice by T Cells Specific for Neuromyelitis Optica Autoantigen Aquaporin-4
Published on: August 21, 2017
Influenza-associated monophasic neuromyelitis optica
Yoshikazu Nakamura1, Ken Ikeda, Yasuhiro Yoshii
1Department of Neurology, Toho University Omori Medical Centre, Japan.
Internal Medicine (Tokyo, Japan)
|August 2, 2011
Summary
Influenza A infection can trigger neuromyelitis optica (NMO), a rare autoimmune disorder. This case highlights pediatric NMO with a single attack, negative AQP4 antibodies, and a post-influenza onset.
Area of Science:
- Neurology
- Immunology
- Infectious Diseases
Background:
- Neuromyelitis optica (NMO) is an inflammatory demyelinating disease affecting the optic nerves and spinal cord.
- A parainfectious etiology is suspected in some NMO cases, with viral infections implicated.
- The role of anti-aquaporin 4 (AQP4) antibodies in NMO pathogenesis is well-established.
Observation:
- A 15-year-old girl presented with symptoms of optic neuritis and myelitis following Influenza A infection.
- Neurological examination revealed significant visual impairment, bladder dysfunction, and lower extremity sensory and motor deficits.
- Brain and spinal MRI showed demyelinating lesions, while serological tests were positive for influenza IgM but negative for AQP4 antibodies.
Findings:
- The patient was diagnosed with monophasic neuromyelitis optica associated with influenza A, meeting the revised 2006 NMO diagnostic criteria.
- This case represents the first reported instance of influenza A-associated NMO in a pediatric patient with an anti-AQP4 antibody-seronegative status and a monophasic course.
- Treatment with methylprednisolone and prednisolone led to significant clinical improvement and sustained remission for three years.
Implications:
- This case expands the understanding of NMO's diverse etiologies, particularly the potential role of influenza A in triggering the disease in younger individuals.
- The findings suggest that NMO can occur in an anti-AQP4 antibody-seronegative form following viral infections, challenging traditional diagnostic paradigms.
- Further research is warranted to elucidate the mechanisms underlying post-infectious NMO and its specific triggers, especially in the pediatric population.
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