Cytomegalovirus, or CMV, is caused by a virus belonging to the Herpes virus family. The virus is very common and infects many people, but disease usually occurs in immune-compromised people, such as AIDS, cancer and transplant patients. CMV retinitis is a common infection of AIDS patients, whom the virus infects and damages the retina of the eye. Infection usually occurs in both eyes and patients usually don't experience immediate symptoms. If left untreated, the condition may lead to blindness.
Symptoms
According to The Merck Manuals Online Medical Library, initial infection with CMV has no symptoms but produces flu-like symptoms that include fever and fatigue in a small number of people. As CMV infection progresses, damage occurs in the retina, which is responsible for vision. Although painless, the patient may experience blind spots, floating specks, light sensitivity, eye redness and blurred vision. As time goes by, sudden vision loss and flashes of light may also occur, which may spread to both eyes. A more serious symptom is retinal detachment in which the retina becomes detached from the other tissues in the eye. The retina is unable to function after detachment and this could lead to permanent loss of vision.
Diagnosis
CMV retinitis is diagnosed by an ophthalmic examination. Medication is put into the eyes to dilate the pupil, which makes it easy for the doctor to observe the internal portion of the eye. The doctor is able to see physical damage caused by the virus. Blood and urine tests may also be performed to detect the presence of the virus, according to MedlinePlus.
Treatment
Antiviral drugs are used to slow down the CMV infection, but they cannot cure it. Drugs include cidofovir, ganciclovir and foscarnet, and they are usually administered intravenously or through a catheter. A new implant treatment called Vitrasert is inserted directly into the eye, where it releases a small amount of the drug ganciclovir during a five- to eight-month period. The implant is done as an outpatient procedure and is inserted quickly with no side effects afterward, according to the University of Michigan Kellogg Eye Center.
Complications
Several complications are associated with CMV retinitis. The main one is retinal detachment, which may lead to severely limited vision and eventually blindness. Other complications are kidney impairment and low white blood cell count, which is due to the drugs used to treat the condition, according to MedlinePlus.
Prevention
CMV retinitis is very common in immune-compromised people. A good preventive measure is for AIDS patients to get regular eye checkups even if no symptoms are present, according to MedlinePlus.
