Ocular mucous membrane pemphigoid
Ocular mucous membrane pemphigoid is a type of scarring conjunctivitis. It affects the membrane that lines the eyelids and covers the white of the eye (the conjunctiva).
In the UK, around 1 in a million people have ocular mucous membrane pemphigoid. If it’s not treated, it can lead to blindness.
Ocular mucous membrane pemphigoid (OMMP) is a very rare condition affecting the conjunctiva – the thin membrane that lines the eyelids and covers the eyeball.
“One person in every million has OMMP in the UK”
One person in every million has OMMP in the UK. Actual figures may be higher because accurately diagnosing the condition takes time.
What is ocular mucous membrane pemphigoid?
Ocular mucous membrane pemphigoid is part of a wider group of autoimmune conditions called mucous membrane pemphigoid (MMP). MMP can occur in a single site or multiple mucosal sites.
Mucous is the thin skin that covers the inside surface of parts of the body such as the nose and mouth, and eyes and produces mucus to protect them.
What is ocular mucous membrane pemphigoid?
When MMP occurs in the eyes, we call it ocular mucous membrane pemphigoid.
The condition mainly causes inflammation and scarring of the affected eye tissue and eyelids (MMP is sometimes also known as cicatricial pemphigoid – cicatricial means scarring).
Ocular mucous membrane pemphigoid is a chronic and often severe condition with no cure.
The rate at which scarring progresses can vary, leading to irreversible sight loss in particularly severe cases. However, treatments are available for ocular mucous membrane pemphigoid, which can be effective in helping relieve symptoms. There are no treatments that directly slow the progression of scarring in MMP.
Sometimes, the disease can go into ‘remission’ on treatment meaning the inflammation may get better, or the condition may become significantly less severe.
What are the causes of ocular mucous membrane pemphigoid?
Ocular mucous membrane pemphigoid is an autoimmune disease. It broadly means the body’s immune system is mistakenly attacking healthy tissue.
Our immune systems are designed to produce antibodies to help us fight infections. When autoimmune disease occurs, the immune system begins to produce antibodies which attack normal tissue instead (known as autoantibodies).
There are many different examples of autoimmune diseases which affect other parts of the body. In mucous membrane pemphigoid, it is the mucous membranes found in areas of the body that are naturally wet and moist, such as inside the mouth, throat and nose, as well as the eyes and genitals, that are affected, and areas of the skin. Other signs are lashes turning over or inflammation.
Who is at risk of ocular mucous membrane pemphigoid?
Most people with the condition are between 60 and 80, but in very rare cases, it can start in early childhood. It is believed around 60% of people living with the condition experience signs involving the eyes as well as other areas of the body (known as mucous membrane pemphigoid or MMP).
For others, it is only their eyes that develop symptoms (known as ocular mucous membrane pemphigoid or OMMP). When this happens, the conjunctiva, the thin mucous membrane covering the eyeball and inside the eyelids, becomes inflamed, and scarring develops.
Blistering is among the most common symptoms when mucous membrane pemphigoid affects other body areas. As with all autoimmune conditions, it is not fully understood what causes some people to develop ocular mucous membrane pemphigoid while others don’t.
However, researchers believe that for all autoimmune diseases in general, there may be a combination of genetic and environmental factors involved.
While ocular mucous membrane pemphigoid is not an inherited condition, meaning it is not directly passed down through families via specific gene patterns, there is a theory that some people may be genetically predisposed to developing it – meaning they are more likely to develop it during their lifetime.
Some people first notice ocular mucous membrane pemphigoid symptoms after eye surgery, such as eyelid surgery. It is not contagious, so you can’t ‘catch’ ocular mucous membrane pemphigoid from someone else.
What are the signs of ocular mucous membrane pemphigoid?
Ocular mucous membrane pemphigoid is a chronic condition that can often be severe. The scarring associated with the condition can lead to sight loss, which may be severe in some cases, resulting in blindness.
However, as well as providing relief from symptoms, treatment can help prevent sight loss from ocular mucous membrane pemphigoid from happening. Different sub-types of mucous membrane pemphigoid involving other areas of the skin and body may cause slightly different symptoms to present.
However, for ocular mucous membrane pemphigoid, which concerns only the eyes. People may experience the following:
Conjunctivitis is often the first symptom, which means the eyes and eyelids become red and inflamed and may also look and feel sticky. It can range in severity, and the eyes may feel very irritated, sore and painful.
Persistent conjunctival inflammation leads to scarring. If the inflammation is severe, the scarring process can happen quite rapidly. However, it may not be possible to see this with the naked eye unless examined closely by a doctor or eye specialist with magnifying tools.
As the condition progresses, scarring can worsen and affect the eyes differently and so you may experience:
- Changes to the eyelids: the gaps between the eyelids and eyeball (the conjunctival fornix) can become smaller, causing lids to appear more droopy or closer together, with less of a gap between them. The eyelids can also begin to turn inwards (known as trichiasis), which means the eyelashes can start to scratch the eyeballs, further adding to the discomfort. The scratching can damage the cornea, the clear window of the eye, which can then become vulnerable to infection.
- Dryness: as tubes that come from the glands and drain tears become blocked, they can become less effective, resulting in the eyes becoming dry. Again, this can further exacerbate symptoms and problems with the eyes.
- Blepharitis: the eyelid margin glands, situated along the edges of the eyelids near the eyelashes, can become blocked, resulting in further swelling, inflammation and irritation.
How is ocular mucous membrane pemphigoid diagnosed?
Because it is a rare condition, ocular mucous membrane pemphigoid is often not a first consideration when a doctor is trying to fund a diagnosis. However, early diagnosis is essential to implement treatments to induce complete remission. Without this, severe scarring can occur, leading to irreversible sight loss.
In the early stages, ocular mucous membrane pemphigoid symptoms can seem very similar to other more common conditions. Ocular pemphigoid can present with conjunctivitis, which can be mild or severe. If this does not improve with antibiotics, or the condition keeps returning despite using antibiotics, you may need a referral to an eye doctor.
If somebody has symptoms in other areas of the skin and body, they would probably be referred by their GP to a dermatologist (skin specialist), who can arrange for a biopsy of the affected areas.
In the case of ocular mucous membrane pemphigoid, when only the eyes are involved, an ophthalmologist (eye doctor) would need to conduct the diagnosis.
What tests can confirm ocular mucous membrane pemphigoid?
Biopsies of the conjunctiva are performed to confirm a suspected diagnosis of ocular pemphigoid. A biopsy is a small piece of tissue taken from the affected area, in this case, the conjunctiva.
Anaesthetic drops are put into both eyes so that the biopsy is painless. The samples are sent off to specialist labs to be analysed. Frequently, a biopsy is also taken from the lining of the mouth. The tissue is tested against antibodies - this is called the direct immunofluorescence test (DIF). A blood sample is also taken. This is tested for the presence of autoantibodies (serology testing or indirect immunofluorescence (IIF)).
How long it takes to get the results can vary between hospitals, but whoever carries out the tests should be able to advise on how long until you’re likely to receive results. Where results indicate that you have ocular mucous membrane pemphigoid, you will usually receive a letter or telephone call arranging a follow-up appointment to discuss treatment options and any further examinations.
You may need further examinations if the test proves negative.
Tests are usually positive for MMP affecting non-ocular sites. In about 50% of cases, they are negative when the eyes are the only site affected by MMP. A negative test in the conjunctiva indicates worse ocular disease and is more likely to have corneal involvement.
How is ocular mucous membrane pemphigoid treated?
There is no cure for ocular mucous membrane pemphigoid. However, treatments are available which can make a big difference to people’s comfort levels and quality of life, as well as slowing down the progression of the condition.
As with other autoimmune diseases, treatment may also help the condition to go into ‘remission’ – meaning signs halt completely or reduce to a much milder level. It is important that treatment for ocular mucous membrane pemphigoid starts as soon as possible, as it is much easier to prevent severe scarring from developing than treating it once it has occurred.
Blindness from very severe ocular mucous membrane pemphigoid cannot currently be reversed once it has happened. Your ophthalmologist will be able to discuss the treatment options for ocular mucous membrane pemphigoid with you and arrange to monitor the progression of the condition.
The ophthalmologist will treat cases depending on the severity of the disease and how fast the disease is progressing. Around 20% of patients with ocular mucous membrane pemphigoid have mild disease and don’t need specific treatment.
However, specialised treatments are required for most patients to prevent or slow disease progression.
Eye drop and ointment treatments alone have not been found to be fully effective but are used for symptom relief. Ocular mucous membrane pemphigoid usually requires specialists to prescribe medications given by mouth known as immunosuppressive drugs. These medications modify the immune system whilst making sure the immune system remains active enough to fight infection.
Some of the main treatment options for ocular mucous membrane pemphigoid include the following:
- Immunosuppressive drugs: these are used to treat various autoimmune conditions, often when symptoms are fairly severe. There are different varieties of immunosuppressive drugs – including azathioprine, mycophenolate and dapsone. The aim is to deliver a dose adequate to stop the disease whilst enabling the immune system to continue protecting you from infection.
- Biological treatments/biologics: these drugs may be an option when ocular mucous membrane pemphigoid is particularly severe. They also work by altering the immune system but are designed to be more targeted and ‘block’ specific processes involved in the disease.
- Intravenous immunoglobulin (IViG): this treatment is administered via a drip (where a thin needle is used to connect a vein to a tube carrying liquid). It is designed to replace the antibodies in a person’s system. This therapy is sometimes used alongside other treatments or instead of them.
- Surgery: if severe scarring has caused the eyelids to turn inwards, corrective surgery can sometimes help. This may also be performed to remove eyelashes that can no longer be easily removed with tweezers (to prevent them from scratching the surface of the eye).
Alongside the treatments outlined above, other things can also play an important role in managing ocular mucous membrane pemphigoid.
Managing ocular mucous membrane pemphigoid
You can use hot compresses, massage, hygiene and lubrication to manage ocular mucous membrane pemphigoid. Follow the simple process below:
Apply warm compresses for 10 minutes either with a hot flannel/face cloth soaked in boiled then cooled water to a warm temperature (be careful not to burn yourself) or with a proprietary commercially available eyelid warming device or mask.
Gently massage the upper and lower eyelids with the ring finger moving in a circular motion to liquefy the oils. Commercially available devices might help.
Gently express the oils out of the glands by rolling a cotton wool bud towards the eyelid margin and the lashes. o downwards for the upper lid, or upwards for the lower lid, o be sure to perform expression along the full length of both upper and lower lids.
Prepare a cleaning solution with either of the following: Bicarbonate of soda 1 teaspoon in 1 pint of boiled, cooled water stock solution. Dip a cotton wool bud into the cleaning solution. Gently clean the eyelid margin just behind the roots of the lashes. Use a clean cotton wool bud for each eyelid.
Alternatively, you can use commercially available lid wipes purchased from the chemist, high street optician, or online web equivalent.
Living with ocular mucous membrane pemphigoid
Living with a chronic condition like ocular mucous membrane pemphigoid can sometimes be challenging. While treatments can be very effective, side effects can also occur, so it is important to discuss these with your doctor and attend regular follow-ups so things can be monitored.
Psychological support may not always be routinely offered, but it’s important to be aware that all chronic health conditions can also take a toll emotionally and mentally. Talking to your GP about this is a good idea if you are finding things tough and talking to your loved ones. Explaining what’s happening to your employer can also be very helpful, so they understand what you are dealing with and can support you as needed.
For more information and support, visit PEMfriends.
Last updated August 2023
Saaeha Rauz, PhD FRCOphth, Professor of Translational Ophthalmology
and Consultant Ophthalmologist, Academic Unit of Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham (UK)