Neuromyelitis optica (NMOSD) - Diagnosis, symptoms, and coming to clinic
What is Neuromyelitis Optica Spectrum Disorder (NMOSD)?
Neuromyelitis Optica Spectrum Disorder (NMOSD) is a rare autoimmune neurological condition. NMOSD affects the optic nerves, spinal cord and brain, which can lead to optic neuritis (optic inflammation), transverse myelitis (spinal cord inflammation) and area postrema syndrome (Intractable vomiting/hiccoughs).
In many people, Aquaporin 4 antibodies (AQP4) are identified, but this is not always the case. NMOSD may only have optic neuritis or transverse myelitis but also have an antibody we recognise as being associated with this disorder. A proportion of people will have a different antibody known as Myelin Oligodendrocyte Glycoprotein or MOG. These people are known to us as having MOGAD or MOG Associated Disease and present similarly to NMOSD.
Each person with NMOSD will experience different symptoms and require individually tailored care and support. The symptoms of NMOSD can range from mild to severe. In some cases, there may only be one attack, with good recover and no further relapses for a long time. However, in severe cases, there can be a number of attacks which lead to disability. Disability is driven by relapses, unlike MS, and progressive forms are rare.
Some of the main symptoms of NMOSD include:
- muscle weakness - reduced strength in one or more muscles that affect mobility
- impaired eyesight
- nerve pain - which can be a sharp, burning, shooting or numbing pain
- spasms and increased muscle tone - from nerve damage that affects muscle control
- bladder and bowel and sexual problems
Optic neuritis relates to inflammation of the optic nerve (the nerve that carries messages about vision from the eye to the brain). It causes a reduction or loss of vision and can affect both eyes at the same time. Other symptoms of optic neuritis include eye pain, which is usually made worse by movement, and reduced colour vision where colours may appear 'washed out' or less vivid than usual.
Transverse myelitis is inflammation of the spinal cord. It causes weakness in the arms and legs which can range from a mild 'heavy' feeling in one limb, to complete paralysis in all four limbs. It may cause someone to have numbness, tingling or burning below the affected area of the spinal cord and be more sensitive to touch, cold and heat. There may also be tight and painful muscle contractions (known as tonic muscle spasms). Bladder, bowel and sexual dysfunction are commonly associated in NMOSD.
The NMOSD service
It is essential for people with NMOSD to be treated early in their condition to prevent relapses and disability. Referrals received from consultant neurologists will be accepted, referrals direct from GPs will be accepted if it is likely the patient has NMOSD or if the patient has AQP4 or MOG antibodies
The aims of this NMOSD service are:
- To ensure early correct diagnosis and treatment of adults and children with NMOSD
- Education and support of persons affected by NMOSD
- Be a source of information and education to health care professionals
NHS England has acknowledged NMOSD as a rare neurological condition that requires specialist expertise and funds The Walton Centre NHS Foundation Trust in Liverpool and John Radcliffe Hospital at Oxford to provide the service. These two centres have developed a UK diagnostic and advisory service, are active in research, and collaborate with national and international groups working on NMOSD to raise awareness.
The medical history and clinical examination taken by a neurology specialist will include any previous symptoms or problems in the past to suggest a diagnosis of NMOSD. It is also important to confirm the diagnosis by special investigations:
Magnetic Resonance Imaging (MRI) of the brain and spinal cord
MRI has become a key tool in the diagnosis of NMOSD. Magnetic fields are used to create images of the brain and spinal cord. The person lies in a long tube. The MRI scan takes approximately 45 minutes, it is painless but noisy and you have to lie very still. The MRI of the brain is often normal in NMOSD although up to 60% people with NMOSD may have lesions on the brain, most are asymptomatic. Where someone has had a myelitis, the MRI of the spine often shows inflammation extending over three vertebrae, usually affecting the cervical and thoracic areas, especially during a relapse.
Aquaporin 4 antibody (blood test)
The presence of Aquaporin 4 antibodies is highly specific to a diagnosis of NMO or NMO spectrum disorder. Most people (approximately 80%) have aquaporin 4 antibodies present in their blood.
MOG antibody blood test
We also test for myelin oligodendrocyte glycoprotein antibodies otherwise known as MOG antibodies. Although not classed as NMOSD, people with MOG antibodies are looked after by the NMOSD team as the sites of inflammation tend to be the same, resulting in very similar attacks.
Cerebral Spinal Fluid (CSF) is the watery liquid that surrounds and protects the brain and spinal cord. A lumbar puncture (LP) requires a small amount of CSF to be drawn from the spinal cord with a needle. This only takes a few minutes and hurts a little and so is normally done under a local anaesthetic. Some people can get a headache after the procedure (due to leakage of CSF). It can be avoided by lying flat for a few hours after the test and having plenty to drink. If done during an acute attack of TM there may be increased white cells and raised proteins. A special pattern of antibody proteins called oligoclonal bands (OCB) are usually absent in NMO.
An ophthalmologist is trained to pick up even very small changes in a patient’s vision. Ophthalmoscopy (looking at the back of the eye with an ophthalmoscope) may show swelling of the optic disc. Often swelling is not seen, as the demyelination can be further away from the eye (retro bulbar neuritis).
Visual Evoked Potential (VEP)
Electrodes are placed on the scalp and measure the speed of nerve messages along the optic nerve from the eye to brain in response to being shown a flashing chessboard pattern on a computer screen. Damage to the optic nerve shows slower response time.
Visual Field Tests
These show whether there are any areas of your peripheral vision missing, which can indicate optic neuritis.
This is a series of 13 images that detect minor changes in colour vision sensitivity.
Optical Coherence Tomography (OCT)
This is a very fast scan that can measure the thickness of the nerve fibres in the optic nerve. At present this is more a research tool than a clinical marker.
How could my condition affect me?
Every person has different symptoms and will require different levels of support and advice from different therapists.
- Neuropathic (nerve) pain arising directly from damaged nerves in the spine, there are no particular triggers, this pain is described as burning, sharp, electrical shock, shooting or an uncomfortable numbness. Medication suggestions are Amitriptyline, Gabapentin, Pregabalin and Carbamazepine.
- Nociceptive (musculoskeletal) pain often has a more obvious cause, such as banging your knee. In NMOSD, the most common cause is pressure on joints from altered gait (the way you walk). Medication suggestions such as Paracetamol or Ibuprofen may be helpful.
- Increased muscle tone and spasms arises from damaged nerves in spinal cord that affects the control of muscles, including when they contract and relax. This can present as prolonged contractions of the muscles, which are called spasms. Medication suggestions are Baclofen, Tizanidine, Gabapentin.
- Tonic spasms this is a painful spasm of the muscles that lasts seconds to minutes but frequently. Often, it’s controlled by Carbamazepine at low doses.
- Joint stiffness is a discomfort after a period of inactivity (such as waking up in the morning or sitting for an extended period of time. Medication suggestions are Baclofen, Tizanidine, Dantrolene. Exercises and stretching are often useful.
- Muscle weakness is a reduction in the strength of one or more muscles affecting mobility (legs) or activity (arms). There are no medications to improve weakness. Exercise and stretching are good.
- Bladder symptoms include urgency, hesitancy, frequency and nocturia (passing urine at night) and retention (unable to pass urine) due to damage on the spinal cord. Medicines like Oxybutynin, Tolterodine may be helpful or learning self-catheterisation, (a very simple technique).
- Bowel symptoms mainly constipation, urgency and sometimes faecal incontinence are also due to damage on the spinal cord and immobility. Laxatives, a high fibre diet and fluids as well as abdominal massage may be useful.
- Sexual dysfunction where men may experience difficulty getting an erection, or reaching orgasm, and women may also have difficulty reaching orgasm due to a lack of sensation and numbness.
- Osteoporosis (brittle bones) may be the result of long-term use of steroid medication or a lack of weight-bearing activities.
- Depression – changes in lifestyle associated with the complications of NMOSD can increase the risk of developing depression.
Why do symptoms persist after the relapse has recovered?
When a relapse occurs, there is inflammation and swelling in the brain, so messages cannot get from the brain to their target, eg a relapse of the spinal cord does not allow nerve messages to pass to the area below the inflammation causing the symptoms of transverse myelitis.
Over time there is some spontaneous recovery and symptoms may improve over time. Most recovery takes place in the first 6-9 months but can continue with smaller improvements for up to two years. However, if the nerves have been damaged or destroyed new pathways cannot be made, resulting in permanent damage.
Some people will have very few residual symptoms from a relapse, whilst others may have more. The severity will also be different between individuals.
Symptoms such as loss of vision/visual changes as a result of damage to the optic nerve, weakness or sensory changes in limbs due to damage to the spinal cord, which may affect legs and arms and pain caused by damage to the spinal cord
The symptoms are treated to try and improve your daily living either with medication or therapy. There is no ‘right’ drug as individuals respond differently to different treatments. The overall aim of symptom management is to control or reduce symptoms impairing functional abilities and quality of life. You may have to trial several regimes to find the most suitable drug for you.
What about managing permanent disability?
Many symptoms overlap with each other for example pain interferes with all activities such as housework, work, exercise and consequently has an impact on a person’s mood, affecting family relationships. Though problems can be tackled on their own a multi-disciplinary approach is essential to provide holistic care.
Combined efforts by doctors, nurses, occupational therapists, physiotherapists, orthoptics and social services will help the complex requirements of the individual patient. Visual aids, walking aids, motorised wheelchairs, and home adaptations can improve quality of life remarkably and many patients live an active life.
Coming to clinic
If this is your first visit to the clinic, we understand that it can be a worrying time, so remember we are here primarily to offer you support. We see people from all over the UK. The clinic also caters for patients who have conditions very similar to NMOSD, or if a clear diagnosis hasn’t yet been made.
Not everyone referred to this clinic has NMOSD. Sometimes the diagnosis of NMOSD will already be clear, whilst other times you, your GP or your neurologist may be wanting another opinion about your symptoms. We recognise that you may have seen a lot of specialists before you reach us and that your symptoms may have been present for many months, or even years.
What happens at the first visit?
We have recently changed the way in which we operate seeing new patients. To see people as soon as possible, we now carry out a virtual appointment as soon as possible after the referral is received and the relevant scan and documentation are obtained and reviewed. This allows us to assess people much more quickly. A full assessment will be made of your condition and your medical history will be reviewed. You will be able to ask any questions and encourage to be actively involved in you care.
We then follow up with a face to first visit in the following three months. New patients who come to clinic for the first time will be seen in the morning. Follow up patients take place in the afternoon when the rest of the multidisciplinary team are available.
You will then go on to see the nurse specialist and other therapists. This includes Physiotherapist, Occupational Therapist, Dietitian and Orthoptist. At the Oxford Centre, you may also visit the Oxford Eye hospital. The Walton Centre also provides a counsellor If any further investigations/appointments are required (such as MRI), where possible we aim to complete these on the same day as your next appointment unless you state that you would prefer to come back a separate day
As we are a teaching hospital, we may have medical students or other healthcare professionals sitting in the clinic observing – please say if you would rather they were not present.
Should I bring someone with me?
It is a good idea to bring someone with you to the clinic, even if you would prefer, they remain in the waiting room during consultation.
What will the doctor want to know?
It is important that we go over all of your symptoms from the start, although we realise that you may have told the same story to several doctors. This ensures nothing has been overlooked. We are most interested in the symptoms you have experienced and their timing, rather than what other doctors may have explained to you or tests you may have had in the past. It is usual to perform a full neurological examination so that we can properly assess you.
Getting a diagnosis
The doctors in the clinic will try to provide you with a complete diagnosis and give you time to ask any questions you might have. It can be helpful to write down any questions you think of before the visit, or we may suggest a phone call with your NMOSD Specialist Nurse soon after your first appointment to go through questions that often arise after you leave.
There are some cases where further tests may be required to reach a diagnosis or to exclude other diagnoses. Sometimes we cannot be absolutely certain of the diagnosis and this can be one reason to attend the clinic again, so that we can assess whether there has been any change in your symptoms.
How long will the clinic appointment take?
You may meet all the members of the NMOSD team: the Consultant; NMOSD Fellow; Specialist Nurses; Therapists (occupational therapist; Orthoptist; Physiotherapist; Dietitian and Psychologist. This can take around three hours.
Do I need to come back a second time?
The decision whether to attend the clinic a second time or regularly (usually every six months to one year) will depend upon your condition, and on factors such as the distance involved. A follow up appointment can be useful to discuss the management of any relapses or symptoms, and to provide advice, support and information about current research. If you are not able to attend, it is possible for a telephone or virtual follow up. The doctor who sees you will also ensure that your GP and local team are aware of everything by letter.
Do I continue to see my local neurologist?
Although your local Neurologist may not always be able to see you for the same length of time at each consultation as we are able to, it is important to continue to see them even if you are coming regularly to our clinic. We work under a “shared care” system so that your local teams are aware of what the NMOSD team suggests and vice versa.
How common is NMOSD?
NMOSD is a very rare condition. In Europe, it is estimated that there is one case of NMOSD for every 100,000 people potentially affecting less than 1000 people in the UK. NMOSD may be more common in people of Asian and African descent. NMOSD can affect any age group including children. NMOSD is predominantly a female disease with a ratio of 8 females:1 male affected
Who is at risk of developing NMOSD?
NMOSD is not hereditary (it is very rarely found in more than one family member). People who inherit a tendency to develop an autoimmune disease are at increased risk of developing another autoimmune disease, such as diabetes, Lupus or thyroid disease. You cannot pass on an increased risk of getting NMOSD to your family. It is not possible to catch NMOSD from another person.
Why do some people develop NMOSD?
We do not fully understand the reason why someone develops NMOSD. As with all autoimmune conditions, the immune system mistakes certain parts of our body and decides it is 'foreign' and therefore tries to damage or destroy it. Sometimes the first episode of an NMOSD attack can be preceded by an episode of flu or other virus or even a vaccine. It is thought that the immune system may overreact to this and attack the body in error.
How severe can NMOSD be?
Every person is affected differently. Some people only experience one attack or mild attacks and can have near complete recovery whilst others can be left with physical or visual symptoms which can have a significant impact on their lives. The aims of our service is to assess and treat you quickly and, where we suspect you are at risk of further attacks, treat you to help prevent these happening. Our understanding NMOSD evolves all the time and from the implementation of the service is 2010, treatment and relapse prevention success have greatly improved.
How effective is current treatment?
The majority of NMOSD patients are on immunosuppressants with Mycophenolate and Azathioprine along with steroids being the most popular first line treatment choices. For some patients whose relapses are not well controlled on these drugs, the second line treatment options include Rituximab and IVig infusions. Current treatment reduces the number of relapses to an average of 0.13% (mean average - 1.57% before treatment with five-year follow up)
Can I still travel abroad with NMOSD?
Providing you have the correct immunisations for the country you are visiting you should be safe to travel. If you are taking immunosuppressive medications you should avoid 'live' vaccines such as yellow fever - check with your NMOSD nurses. Remember to be vigilant for coughs/colds/urine infections whilst away and ensure your travel insurance company are fully aware of any medical conditions.
What does the future hold for NMOSD?
As our knowledge and understanding of this rare condition grows so does our options for treating it. We constantly adapt treatment based on the individual and carry out a great deal of research at both of our UK centres and are involved with studies worldwide. You may well be asked to take part in these studies and your help will greatly enhance future care for NMOSD patients. We are also actively involved with trials of new treatments. There are three treatments currently in trial for relapse prevention in NMOSD and they are showing promising results. These drugs are Inebilizumab, Eculizumab and Satralizumab. Once studies are complete, these drugs will hopefully offer more treatment options for our patients.
Are there any dietary considerations/restrictions for people with NMOSD?
There are no specific requirements from a dietary point of view but eating a healthy diet is recommended.
Every month we hold a webinar session on a different topic in the NMOSD world and would like you to join us. To join one of our webinars, you will need access to a computer with speakers. You can also phone in and just listen but you will obviously not be able to see the slides without a computer. During the presentation, you can send us messages with your questions and we will answer these at the end of the session. We cannot discuss individual issues due to confidentiality. If you would like to register, please send us an email to email@example.com. You can access the recordings from previous sessions here.
Your personal information
As with all NHS patients, your personal information is recorded in your medical records, which are confidential and held securely within the Walton Centre Foundation Trust. As we are also a research centre for NMOSD, you will be asked to participate in research, but this is never obligatory and you have every right to say no thanks. With your written permission, we also record information about your symptoms on a secure database that can only be accessed by the clinic team using a password. This database allows us to study the different presentations of the cases we see, which we hope will lead to a greater understanding of the disease process. We would never publish this information in a way that could identify an individual. Please let someone know if you have any concerns about this, or if you wish to have your details removed, this would not affect your future care in any way, and you do not have to give a reason.
- Last Updated:05 October 2022
- Review Date:
- Author:Sam Linakar
Neuromyelitis Optica Spectrum Disorder (NMOSD) is a rare neurological condition. NMOSD affects the optic nerves and spinal cord, which can lead to optic neuritis and transverse myelitis. This leaflet provides information on diagnosis, symptoms, and coming to clinic for NMOSD.