Cytomegalovirus retinitis

An eye disease caused by cytomegalovirus infection

Cytomegalovirus retinitis is an inflammatory condition of the retina of the eye caused by infection with the cytomegalovirus (CMV). It is a significant cause of visual impairment and blindness, particularly in individuals with immunocompromised conditions such as HIV/AIDS.

Pathophysiology

Cytomegalovirus is a member of the Herpesviridae family and is a common virus that can infect individuals of all ages. In healthy individuals, CMV infection is usually asymptomatic or causes mild symptoms. However, in individuals with weakened immune systems, such as those with acquired immunodeficiency syndrome (AIDS) or those undergoing immunosuppressive therapy, CMV can reactivate and cause severe disease, including retinitis.

CMV retinitis occurs when the virus infects the retinal cells, leading to necrosis and inflammation. The infection typically starts in the peripheral retina and can progress to involve the central retina, leading to vision loss. The virus causes destruction of the retinal tissue, resulting in characteristic lesions that can be observed during an ophthalmologic examination.

Clinical Presentation

Patients with CMV retinitis may present with symptoms such as:

• Floaters
• Blurred vision
• Loss of peripheral vision
• Photophobia
• Sudden loss of vision in severe cases

The condition is often bilateral, affecting both eyes, although it may initially present in one eye.

Diagnosis

Diagnosis of CMV retinitis is primarily clinical, based on the characteristic appearance of the retina during a dilated fundoscopic examination. The retina may show areas of whitening and hemorrhage, often described as a "pizza pie" appearance. Polymerase chain reaction (PCR) testing of the vitreous humor or aqueous humor can confirm the presence of CMV DNA, supporting the diagnosis.

Treatment

The primary goal of treatment is to control the infection and prevent further vision loss. Antiviral medications are the mainstay of treatment and include:

• Ganciclovir
• Foscarnet
• Cidofovir

These medications can be administered intravenously, orally, or via intravitreal injection directly into the eye. In some cases, a ganciclovir implant may be surgically placed in the eye to provide sustained drug delivery.

Prognosis

With appropriate treatment, the progression of CMV retinitis can be halted, and vision can be preserved. However, if left untreated, the condition can lead to retinal detachment and permanent blindness. Regular monitoring and early intervention are crucial for individuals at risk.

Prevention

Preventive strategies include regular ophthalmologic examinations for individuals with HIV/AIDS and maintaining a strong immune system through antiretroviral therapy. Prophylactic antiviral therapy may be considered in high-risk patients.

Related pages

• Retinitis
• Cytomegalovirus
• HIV/AIDS
• Immunosuppression