Multifocal choroiditis: symptoms, diagnosis and treatment

The uvea is the middle layer of the eye, made up of the iris, the ciliary body and the choroid. The NHS describes uveitis as inflammation inside part of the eye, a rare condition that is important to treat early to avoid long-term complications such as vision loss. Multifocal choroiditis (MFC) is one of the posterior forms of uveitis, in which the inflammation involves the choroid and creates multiple small lesions.

NORD describes MFC as characterised by swelling of the eye (uveitis) and multiple lesions in the choroid. It is part of a family of white dot syndromes and related conditions that eye specialists distinguish by the pattern and location of lesions. Because the diagnosis depends on careful eye examination and imaging, it is made by an ophthalmologist, usually in a uveitis or medical retina clinic.

NORD lists blurry vision, floaters, sensitivity to light, blind spots and mild eye discomfort. The NHS gives broadly similar symptoms for uveitis in general: eye pain, red or watery eyes, reduced or blurred vision, sensitivity to light, and flashes and floaters or dark spots, which may develop over hours and days or more gradually over weeks and months. The NHS notes that sometimes uveitis does not cause any symptoms.

• Blurred or reduced vision.

• Floaters and dark spots, sometimes flashes.

• Blind spots in the field of vision.

• Light sensitivity.

• Mild eye discomfort.

The NHS says to ask for an urgent GP appointment or get help from NHS 111 if you have eye pain, sensitivity to light, changes in vision such as flashing or blurring, or very red eyes. It says to go to A&E or call 999 if you cannot see (loss of vision). A new shower of floaters, flashes or a dark curtain across the vision can also be signs of retinal detachment, which the NHS says needs urgent treatment.

If you already have multifocal choroiditis and your vision suddenly changes, for example a new blind spot or distortion, contact your eye clinic the same day or use NHS 111 if you cannot reach them.

NORD says the cause of multifocal choroiditis is unknown, and that it is seen most frequently in women aged 20 to 60 and usually affects both eyes. The NHS says that in most cases of uveitis the cause is unknown, although some are linked to autoimmune conditions, some infections, injury to the eye or, rarely, a growth in the eye. Because several infections and inflammatory conditions can produce similar lesions in the back of the eye, doctors often arrange blood tests and chest imaging to look for other causes before settling on the diagnosis.

The sources read for this guide do not give a detailed diagnostic protocol, so this is described in general terms. An ophthalmologist examines the back of the eye through dilated pupils, and imaging tests photograph and scan the retina and choroid to map the lesions and look for complications such as fluid or new abnormal blood vessels. Tests for infection or systemic inflammation may be requested to exclude look-alike conditions.

The NHS says that if a GP thinks you have uveitis they will refer you to an eye specialist and that you will usually be seen within 24 hours. After treatment starts, you will be seen again to see how the treatment is working, check for side effects and look for complications such as vision loss.

NORD says MFC is generally treated with steroid medication that can be taken orally or injected into the eye. The NHS says that for uveitis in general, treatment usually includes a combination of medicines to get rid of any infection, reduce inflammation and relax the eye and reduce pain, and that if it is very severe or keeps coming back you may be offered medicines to reduce the activity of the immune system and to reduce inflammation, such as TNF inhibitors, as well as other treatments.

Because treatment may be long-term, monitoring for side effects is a major part of care. Steroids taken for long periods can have side effects that need regular checks. Do not stop steroid tablets suddenly without medical advice.

NORD describes MFC as chronic, so symptoms may return or worsen even after successful treatment. The NHS notes that uveitis usually gets better quickly with treatment but can come back over time. In practice that means regular follow-up with an eye specialist, prompt reporting of new symptoms, and attention to the complications that can accompany long-term inflammation.

Living with a rare eye condition can be unsettling, particularly when it affects both eyes. If your vision is affected long term, the NHS vision loss pages describe low vision aids, practical support and registration as sight impaired. Speak to your ophthalmologist about driving, work and any need for a sight-impairment assessment.

Uveitis is managed in NHS eye clinics, often with specialist uveitis services that work with rheumatology and other teams. Private ophthalmology consultations are available and can provide a second opinion or faster access to imaging, but long-term immunosuppression usually needs a coordinated plan with monitoring blood tests, which NHS teams commonly provide.