Neuromyelitis Optica (NMO) Spectrum Disorders

updated August 2011

What is Neuromyelitis Optica (NMO)?

Neuromyelitis Optica (NMO) is an inflammatory, demyelinating disease of the central nervous system that is characterized by severe relapsing attacks of optic neuritis and transverse myelitis, which unlike the attacks in multiple sclerosis (MS), commonly spare the brain in the early stages.

Why is early and accurate diagnosis important?

• MS is the most commonly diagnosed neurological disorder affecting young people, but lacks a diagnostic biomarker
• A majority of NMO patients, typically women, are initially misdiagnosed as having MS
• Proper diagnosis is important because NMO is generally more debilitating than MS and optimal treatments for the two diseases differ
• NMO is treated by immunosuppressant therapy and MS is treated by immunomodulation therapy
• If not treated appropriately, within five years 50% of NMO patients lose functional vision in at least one eye or are unable to walk
• Unlike MS, where most disability occurs during the late progressive phase of the disease, long-term disability for NMO is related to the frequency of attacks
• In addition to improving patient outcomes, early diagnosis may also reduce health-care costs since NMO treatment is typically less expensive than MS treatment

Tests

In 2004, Mayo Clinic identified the first biomarker specific for NMO. Second generation testing (by ELISA methodology) is now available for serum specimens. If the value is between 1.6-4.9 units, the specimen will be reflexed to an alternative in-house assay for validation. Spinal fluid testing is also offered.

A positive result for aquaporin-4 (NM0)-IgG is consistent with NMO or an NMO-spectrum disorder (i.e., incomplete forms of NMO). A positive result in a patient with transverse myelitis or optic neuritis is a predictor of future attacks. which justifies initiation of appropriate immunosuppressive therapy at the earliest possible time.

• Neuromyelitis Optica (NMO) Evaluation w/Reflex, Serum #60796
• Neuromyelitis Optica (NM0) Autoantibody, IgG, Spinal Fluid #83936

Video

Testing for Neuromylitis Optica by Sean Pittock, MD, Co-Director of the Clinical Neuroimmunology Laboratory, Mayo Clinic

A Patient’s Story

Courtney uses her violin to continue her fight against a serious autoimmune disease

Word of the recital had spread and Courtney’s friends and admirers responded enthusiastically. It was her first time on stage as a soloist since she’d suffered a devastating loss of vision after developing neuromyelitis optica (NMO).

Learn more...

 

Clinical Reference

1. Wingerchuck DM, Lennon VA, Luccinetti CF, Pittock SJ, Weinshenker BG: The Spectrum of neuromyelitis optica. The Lancet Neurology 2007;805-815.