Study supports existence of HIV-induced uveitis

This article in the July issue of Ophthalmology reports six cases of untreated HIV-induced uveitis that all had a highly positive intraocular:plasma HIV-1 RNA ratio and similar ocular presentation.

The authors provide an air-tight case for HIV causation of anterior uveitis in this untreated cohort. In the past, I found it puzzling when ophthalmologists obtained HIV testing as part of a routine work-up of anterior uveitis patients with no other manifestations of intraocular opportunistic infections. However, this report verifies an earlier report that indeed HIV uveitis exists.

It is likely seen in roughly 10 percent of untreated HIV-positive patients and may be difficult to detect due to its indolent nature. Based on negative serologic and ocular fluid PCR data for known infectious agents, the relatively solid evidence of HIV load reductions in intraocular fluids with therapy, and the positive intraocular to plasma HIV load ratios, it is unlikely that other known pathogens are responsible for this anterior uveitis. This uveitis improves with HAART, in contradistinction to immune recovery uveitis, which worsens with this therapy.

The patients were referred for uveitis unresponsive to corticosteroids. They had mild intraocular inflammation predominantly in the anterior chamber and vitreous and no retinal lesions. Four also had vitritis. Four were known previously to have HIV; two were diagnosed during work-up.

The six patients lacked other ocular opportunistic infections (by clinical exam) and had negative laboratory work-up for syphilis and TB and negative intraocular fluid PCR for cytomegalovirus, herpes simplex virus, varicella zoster virus and toxoplasmosis. Plasma HIV load was an average of 218,688 copies/ml, whereas intraocular HIV load was 20,937,755 copies/ml. Average CD4 count was 192.

The patients had decreased vision (CF to 20/30) but no redness or photophobia. Mild to moderate (1-2+) anterior chamber cells and keratic precipitates were present in all of them. Posterior synechiae occurred in two patients and IOP elevation (>25mmHg) in three. Cataract, a presumed incidental finding, caused significant visual loss in two patients.

Within weeks of initiation of treatment with highly active anti-retroviral therapy (HAART), intraocular inflammation disappeared completely in all patients. Follow-up plasma and aqueous HIV viral load, obtained in three patients, revealed undetectable plasma levels in all of them and undetectable intraocular fluid levels in two, with low levels (1940 copies/ml) in one.

The authors advise that HIV-induced uveitis should be suspected in HAART-naive HIV-positive patients or in those in whom this treatment fails and who have anterior uveitis without any retinal lesions and exhibit no response to topical corticosteroids. They further recommend that if intraocular fluid analysis demonstrates negative results for opportunistic ocular pathogens, HIV-induced uveitis should be suspected, and a quantification of HIV-1 RNA in intraocular fluids and plasma should be performed.