Cytomegalovirus (CMV) Retinitis

What is cytomegalovirus retinitis?

Cytomegalovirus (CMV) retinitis is a serious eye infection. It often happens in people with immune systems that don’t work as well as they should. The term “retinitis” means inflammation of your retina, which is the part of your eye that senses light.

CMV is a necrotizing virus, meaning that the virus destroys tissue. It’s part of the herpes family of viruses. Most people get CMV at some point in their lives and don’t even know it. But the virus can reactivate in people with weakened (compromised) systems, sometimes causing CMV retinitis.

This includes people who:

• Have HIV/AIDS.
• Are receiving chemotherapy.
• Take immunosuppressant medications because they’ve had an organ transplant, bone marrow transplant or have autoimmune conditions.

CMV retinitis can result in long-term vision loss. In fact, it’s the main cause of blindness among people with HIV/AIDS.

What are the signs and symptoms of cytomegalovirus retinitis?

You may not have symptoms of CMV retinitis right away. When you do develop them, symptoms may include:

• Floaters in your eye.
• Blind spots that move (scintillating scotoma).
• Decreased side vision (peripheral vision).
• Seeing wavy images (metamorphopsia).
• Blurred vision.
• Sensitivity to light (photophobia).
• Red eye.
• Eye pain.

The symptoms may start in one eye and then go on to your other eye.

What causes cytomegalovirus (CMV) retinitis?

If you’re infected with CMV, the virus can affect your retina, causing CMV retinitis. In adults with weakened immune systems, this is usually a reactivation of the virus rather than a new virus.

How is cytomegalovirus (CMV) retinitis diagnosed?

An ophthalmologist, or another type of eye care provider, will talk to you and ask you about your medical history and symptoms. Then they’ll do an eye examination after dilating your eyes.

Dilated pupils open widely, making it easier to see inside your eyes. Your provider will examine your retinas and other areas of your eyes for signs of disease. If you have retinitis, your provider may order lab work to identify its cause.

How is cytomegalovirus (CMV) retinitis treated?

Antiviral medicines can treat CMV retinitis, but they can’t cure it.

Your provider may decide to give you one — or a combination — of the following antiviral medications:

• Valganciclovir, given orally.
• Ganciclovir, given intravenously (IV) or as an intravitreal injection (IVI, or a shot into your eye).
• Foscarnet, given as an IV or IVI.
• Cidofovir, given as an IV or IVI.
• Letermovir, given orally.
• Fomiversen.

Treatment takes weeks because there’s an initial period of therapy followed by maintenance therapy.

Complications of CMV retinitis treatment

Antiviral treatment of CMV retinitis may cause your immune system to have a strong response, which can lead to uveitis. Uveitis causes eyes to be red, swollen and painful.

Sometimes, the drugs that treat CMV retinitis stop working for you. There are treatments that may help with ganciclovir-resistant CMV retinitis. These include leflunomide and T-lymphocyte infusion.

What can I expect if I have CMV retinitis?

The best prognosis (outlook) happens with prompt treatment. Untreated CMV retinitis can lead to low vision, even to the point of blindness.

Another condition that may happen as a result of CMV retinitis is retinal detachment, which means that your retina tears away from its supporting tissue. You can have surgery to repair this serious condition.

When should I see my healthcare provider?

If you have any sudden changes in eyesight — like dark spots in your vision or pain — get immediate medical help. Retinal detachment is a medical emergency.

It’s important to have regular eye exams if you have a weakened immune system.

What questions should I ask my healthcare provider about CMV retinitis?

You may want to ask your provider some questions about CMV retinitis, including:

• How often should I schedule appointments?
• Is there anything I should avoid?
• How long will treatment last?
• When should I call you or go to an emergency room?
• Can you provide resources to help me cope with vision loss?
• Am I eligible for clinical trials?

What’s the difference between cytomegalovirus (CMV) retinitis and HIV retinopathy?

The term “retinopathy” means disease of the retina. Both CMV retinitis and HIV retinopathy affect your retina, causing damage that can lead to vision loss. But different viruses cause them. The human immunodeficiency virus (HIV) can cause HIV retinopathy, while CMV causes CMV retinitis.

Healthcare providers treat CMV retinitis with antiviral medication. They usually don’t treat HIV retinopathy, also called HIV microvasculopathy.

A note from Cleveland Clinic

If your immune system is compromised, you likely spend a lot of time thinking about your symptoms and inside medical offices. You might not want to make regular trips to the ophthalmologist on top of everything else. But if you develop cytomegalovirus retinitis, you’ll have the best outcome if you get a diagnosis and start treatment as soon as you can. Regular eye exams are important because you might not notice symptoms of CMV retinitis until you start having vision loss.