Cytomegalovirus retinitis

Synonyms

CMV

Overview

Cytomegalovirus retinitis, also known as CMV retinitis, is an inflammation of the eye's retina that can lead to blindness.

Symptoms

Many patients with CMV retinitis have no symptoms. The symptoms of cytomegalovirus retinitis have it usually starting in one eye (and also have the possibility of retinal detachment), presenting as:

  • Blind spots
  • Blurred vision and other vision problems
  • Floaters
  • Specks in your vision

 Retinitis usually begins in one eye, but often progresses to the other eye. Without treatment, progressive damage to the retina can lead to blindness in 4-6 months or less.

Even with regular treatment, the disease can worsen to blindness. This may be because the virus becomes resistant to the drugs so that the drugs are no longer effective, or because the patient's immune system has deteriorated further.

Causes

CMV retinitis is caused by a member of a group of herpes-type viruses. CMV is very common. Most people are exposed to CMV in their lifetime, but typically only those with weakened immune systems become ill from CMV infection such as patients having a history of:

  • AIDS
  • Bone marrow transplant
  • Immunosuppressive Chemotherapy
  • Drugs that suppress the immune system
  • Organ transplant
  • Leukemia

Prevention

Careful hygiene is the best prevention against CMV. What your hands often and avoid hand contact or rubbing the eyes. 
CMV infection that causes symptoms normally occurs only in those with weakened immune systems. People with AIDS who have a CD4 count of less than 100 should be examined regularly for retinitis even if they don't have symptoms.

Diagnosis

CMV retinitis is diagnosed through a standard ophthalmologic exam. Dilation of the pupils and ophthalmoscopy will show signs of CMV retinitis.

CMV infection can be diagnosed with blood or urine tests that look for substances specific to the infection. A tissue biopsy can detect the viral infection and presence of CMV virus particles, but this is rarely done.

Prognosis

The disease will sometimes get worse, even with treatment, because antiviral medications stop the spread of the virus but do not destroy it.

Possible Complications

  • Blindness
  • Kidney impairment (from drugs used to treat the condition)
  • Low white blood cell countwhite blood cell count (from drugs used to treat the condition)
  • Retinal detachment

 

Treatment

Active Cytomegalovirus retinitis is treated by an uveitis and ocular immunology specialist. Because the virus is so threatening to vision, it is usually treated by a vitreo-retinal surgeon, by antivirals such as ganciclovir or foscarnet, which can be taken orally, intravenously, injected directly into the eye (intravitreal injection), or through an intravitreal implant. 

Approved therapies:
Ganciclovir intravitreal implant (Vitrasert) - FDA-approved indication: Treatment of CMV retinitis in patients with acquired immunodeficiency syndrome.

 

Resources

Refer to Research Publications.