The immunosuppression caused by HIV infection increases the incidence of eye infections. However, the risk of serious eye problems associated with advanced immunosuppression, such as blindness caused by cytomegalovirus (CMV) retinitis, is much lower in patients treated with effective antiretroviral therapy (ART). Common problems not unique to HIV-infected patients include dry eye, blepharitis, keratitis, and presbyopia. Infections that may affect the eye include herpes simplex virus (HSV), herpes zoster virus (HZV), and syphilis. More severely immunocompromised patients (CD4 count <100 cells/µL) may experience CMV retinitis, Toxoplasma retinochoroiditis, cryptococcal chorioretinitis, and other conditions. Retinal detachment can result. Kaposi sarcoma (KS) also can affect the eye.
Immune reconstitution inflammatory syndrome (IRIS) may affect the eye in patients with advanced HIV disease soon after the initiation of effective ART. IRIS may lead to exacerbation of a previously treated opportunistic infection or a new presentation (often with unusual manifestations) of a previously subclinical infection. In the case of CMV, IRIS may present as retinitis, or less commonly as uveitis or vitreitis. IRIS retinitis typically occurs in patients whose CD4 counts have increased from <50 cells/µL to 50-100 cells/µL while receiving ART.
Drug-induced ocular toxicity can be caused by rifabutin, ethambutol, and cidofovir, and less often by high-dose didanosine (ddI, Videx), IV ganciclovir, IV acyclovir, and atovaquone.
The patient complains of dry eyes, blurred vision, floaters, sharp pains, flashing lights, central vision loss ("black holes"), vision field defects ("can only see half the page"), or peripheral vision loss ("looks like I'm in a tunnel").
Ascertain the following during the history:
Evaluate recent CD4 cell count and HIV viral load to determine whether the patient is at risk of opportunistic infections as causes of eye complaints. Also, do the following:
Refer to an HIV-experienced ophthalmologist for dilated retinal or slit-lamp examination and definitive diagnosis. If symptoms raise suspicion of serious or vision-threatening conditions such as herpes ophthalmicus, CMV retinitis, or retinal necrosis, ophthalmologic evaluation should occur within 24-72 hours. Note that patients with HSV or VZV lesions in the V1 distribution (including the forehead, eyelids, or nose) should receive urgent ophthalmologic evaluation.
The differential diagnosis includes the following conditions:
The patient may complain of intermittent eye pain, intermittent blurred vision that clears with blinking, and mild eye irritation. The condition worsens with extended reading or computer use. Keratoconjunctivitis sicca is related to HIV-mediated inflammation with damage to the lacrimal glands. It occurs in 10-20% of HIV-infected patients, most often in those with advanced HIV disease. In patients with a CD4 count of >400 cells/µL and no other signs or symptoms, confirm that results of a recent eye examination were normal or refer for same, prescribe artificial tears, and monitor.
Blepharitis is inflammation of the eyelids, a common condition with dry eyes. The patient may complain of discharge and erythema of the eyes or eyelids. Of the bacterial causes, Staphylococcus aureus is the most common. Treatment includes cleaning of the eyelashes with warm water and mild shampoo, and applying antibiotic ointment if indicated.
The patient may complain of photophobia, eye pain, decreased vision, and irritation. Infectious keratitis may be caused by VZV, HSV, CMV, bacteria, fungi, or Microsporidia. VZV and HSV are the most common infectious causes of keratitis in HIV-infected patients. Bacterial and fungal keratitis occur equally in HIV-infected and HIV-uninfected persons. Fungal infections are caused most frequently by Candida species, especially in intravenous drug users. Keratitis may be more severe and may recur more frequently in HIV-infected patients than in HIV-uninfected persons. Evaluation should include slit-lamp examination by an ophthalmologist.
The patient may complain of blurring vision with near or distance vision. Other findings include an abnormal Snellen test or inability to read fine print. The condition may be attributable to presbyopia or other causes. Refer for ophthalmologic examination.
The patient may complain of redness or watering of the eyes, constriction of the pupil, and blurred vision. Anterior-chamber inflammation is fairly common among patients with HIV infection and is often associated with CMV or HSV retinitis. Ocular bacterial infections, syphilis, toxoplasmosis, and tuberculosis can cause severe symptoms. Fungal retinitis rarely causes iridocyclitis. Other causes include other systemic conditions (e.g., reactive arthritis, sarcoidosis) and drug toxicity (e.g., rifabutin, cidofovir, ethambutol). Evaluation should include slit-lamp examination by an ophthalmologist.
Treatment should be directed at the causative pathogen or illness. If drug toxicity is suspected, the offending drug should be discontinued or reduced in dosage, if possible. Topical steroids may be indicated as an adjunctive measure. CMV IRIS may present as posterior uveitis; for suspected IRIS, consult an HIV-experienced ophthalmologist.
The patient typically has no symptoms, but may complain of blurred vision, visual field defects, floaters, or flashing lights. Cotton wool spots on the retina appear as small fluffy white lesions with indistinct borders and without exudates or hemorrhages. Usually, these findings are benign and do not progress. Refer for ophthalmologic examination to rule out other causes.
Patients with retinitis caused by CMV infection may be asymptomatic or may experience blurred vision, floaters, scotomata, or central or peripheral vision loss or distortion. Retinal examination shows creamy to yellowish lesions, white granular areas with perivascular exudates, and hemorrhages ("cottage cheese and ketchup"). The abnormalities initially appear in the periphery, but progress if untreated to involve the macula and optic disc. CMV is a common complication of advanced HIV infection in patients with CD4 counts of <50 cells/µL. Vision loss usually is permanent. Urgent ophthalmology consultation and initiation of anti-CMV therapy are required. See chapter Cytomegalovirus Disease .
The patient may complain of eye pain, decreased visual acuity, and floaters. Rapidly progressing peripheral necrosis frequently causes blindness. Retinal necrosis usually is caused by VZV, although HSV and CMV also have been implicated. Treatment should be initiated urgently.
Toxoplasma retinochoroiditis may occur in patients with CD4 counts of <100 cells/µL and cause blurred vision, visual field defects, floaters, or flashing lights. In HIV-infected patients, ocular manifestations often appear after the infection of the central nervous system with Toxoplasma (see chapter Toxoplasmosis). Retinal examination may reveal yellow-white infiltrates without hemorrhage and active vitreous inflammation. Evaluation requires consultation with an HIV-experienced ophthalmologist. If toxoplasmosis is confirmed or strongly suspected, treatment should be initiated as quickly as possible.
Symptoms or signs of papilledema, optic neuritis, cranial nerve palsies, and visual field defects may indicate encephalopathy, increased intracranial pressure, neurosyphilis, toxoplasmosis, progressive multifocal leukoencephalopathy, meningitis, or central nervous system lymphomas. A thorough neurologic examination is required to determine whether additional diagnostic testing, such as imaging studies or cerebrospinal fluid testing, is needed in addition to ophthalmologic evaluation.
The patient may complain of flashes of light, sudden loss of vision, or both. This condition requires immediate referral to an emergency department.