NMO & Multiple Sclerosis: Did You Know?

What is NMO Spectrum Disorder (NMOSD)?

Neuromyelitis Optica Spectrum Disorder (NMOSD) includes rare, inflammatory autoimmune diseases involving the central nervous system.  As a result of severe inflammation or disease relapses, optic nerves and spinal cord can become injured, resulting in significant loss of mobility, vision or other functions.  In some cases, NMOSD can be life-threatening and may lead to permanent disabilities. NMOSD strikes females up to 10 times more frequently than males, and the average age of first disease episode is 40 years.

NMO is not Multiple Sclerosis

Clinical and laboratory research over the last decade have established that NMOSD and Multiple Sclerosis (MS) are very different conditions.  While NMOSD and MS are both autoimmune diseases, differences between them include their immunology, specific symptoms, severity of relapses and course of disease progression.  Importantly, treatments for NMOSD and MS are also very different, and certain medicines used to treat MS may be harmful to patients who have NMOSD.

NMOSD Needs Rapid Diagnosis & Treatment

group of doctorsWhether the first episode or a future relapse, uncontrolled NMOSD has the potential to cause devastating consequences.   Therefore, recognizing its symptoms to enable rapid diagnosis and treatment are essential.  In 2015, specific criteria differentiating NMOSD from MS were developed by the International Panel for NMO Diagnosis (IPND) in collaboration with the Guthy-Jackson Charitable Foundation (GJCF).  These criteria were published in the journal Neurology and are now widely used throughout the world.  Together, experts defined specific standards to diagnose NMOSD.  These criteria are based on autoantibody status, clinical signs & symptoms and results from magnetic resonance imaging (MRI).  Classical NMO typically refers to patients who have detectable autoantibody to aquaporin-4 (AQP4), whereas NMOSD has to date included distinct MOG-associated disease (MOGAD) and seronegative disease (see below).

Laboratory Tests Aid in NMOSD Diagnosis

Simple blood tests can help to distinguish NMOSD from MS in patients who have similar signs or symptoms.  Anti-AQP4 autoantibody (NMO-IgG) is found in many patients with NMOSD but is not found in those with MS.  Likewise, anti-MOG autoantibody is found in those with NMOSD but not in MS.  Tests for these autoantibodies can be ordered by any licensed physician.  Among those diagnosed with NMOSD, about 75% have anti-AQP4 autoantibody in their bloodstream, and 25% have anti-MOG autoantibody or neither autoantibody (known as double-seronegative NMOSD).

NMOSD or MS: Similar Symptoms—Different Diseases

Symptoms of NMOSD can vary from person to person.  In some cases, these symptoms may resemble MS.  For example, NMOSD and MS may exhibit signs or symptoms resulting from inflammation of the optic nerves or spinal cord, including:

  • Rapid onset of eye pain or vision loss
  • Limb weakness, numbness and/or paralysis
  • Pain or tingling in the neck, back or abdomen
  • Loss of bowel and bladder control
  • Prolonged hiccups, nausea or vomiting

Sometimes these symptoms are temporary and resolve on their own—even so, please discuss them with your doctor.  In other cases, onset of relapse symptoms worsen over time and can lead to significant and potentially permanent disability.  It is essential to report such symptoms as soon as possible to your doctor who can consider NMOSD and ways to reduce risks of relapse.

NMO-IgG Antibody Test

The recent discovery of an antibody in the blood of individuals with NMO gives doctors a reliable biomarker to distinguish NMO from MS. The antibody, known as NMO-IgG, seems to be present in about 70 percent of those with NMO and is not found in people with MS or other similar conditions.

The test can be ordered by any primary care physician.

Other Conditions that Resemble NMO

In addition to MS, other distinct conditions that may resemble NMOSD include:

  • Idiopathic Optic Neuritis (ION)
  • Acute Disseminated Encephalomyelitis (ADEM)
  • Leber’s Hereditary Optic Neuropathy (LHON)
  • Sjögren’s Syndrome
  • Systemic Lupus Erythematosus (SLE)
  • Mixed Connective Tissue Disease (MCTD)

Minimizing the Potential for Misdiagnosis

Today, diagnosing NMOSD is more rapid and accurate than ever before.  This advance enables use of approved treatments as appropriate very early in the course of disease—in turn reducing future severity and disability.  Unfortunately, some patients are still misdiagnosed with MS, even though they have NMOSD.  It is important to consider the diagnosis of NMOSD and to perform autoantibody testing in patients who have hallmark signs or symptoms.  Appropriate autoantibody testing may include anti-AQP4 or NMO-IgG, anti-myelin oligodendrocyte glycoprotein (anti-MOG) and perhaps other autoantibodies.  Detecting and diagnosing NMOSD as early as possible helps to ensure best outcomes.

Therapeutics Approved to Treat NMOSD

After over 100 years with no clinical trials or approved treatment, in 2019-2020 three therapeutics were regulatory–approved as safe and effective to prevent NMOSD relapses.  This quantum leap in treating NMOSD resulted from a close collaboration among patients, doctors, industry leaders, regulatory agencies and GJCF.  Currently, approved agents to treat NMOSD include eculizumab (Soliris; Alexion), inebilizumab (Uplizna; Horizon) and satralizumab (Enspryng; Genentech).  Each of these therapeutics is a monoclonal antibody drug (biologic) that has demonstrated 85% or greater effectiveness in preventing relapses in NMOSD patients who have anti-AQP4 antibody.

Pioneering Research for NMOSD Cures

The GJCF has invested more than $65 million to support leading research resulting in first-ever approved therapies for NMOSD.  Approved therapies are a great step forward—and now GJCF is focused on the science of cures.  Promising new approaches to re-educate the immune system to end NMOSD once and for all are entering clinical trials.  We encourage learning more about the exciting area of immune tolerization and considering participation in this potentially life-saving research.

iNMOtion® to Save & Improve Lives

The GJCF promotes a diverse and inclusive advocacy forum for NMOSD patients, caregivers and all stakeholders.  Resources include the NMOSD Resources app, NMOSD Patient Guide, FAQs and GJCF Breakout Sessions addressing latest topics, Support Groups and more.  To access these resources and learn the GJCF story, visit

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