Abstract
Purpose: :
To evaluate clinical differences between polymerase chain reaction (PCR)-confirmed herpes simplex virus (HSV) and varicella zoster virus (VZV) retinitis. This study also examines the relationship between prophylactic laser demarcation, the subsequent development of retinal detachment (RD) and final visual acuity (VA).
Methods: :
Microbiological records were reviewed to identify all patients at a single academic center treated between April 1, 2000 and December 31, 2008 with a PCR-analysis of intraocular fluids positive for HSV1, HSV2 or VZV. Zone 1 refers to a 3000-um radius centered on the fovea and extends 1500-um nasally from the optic disc.
Results: :
PCR-analysis of intraocular fluids confirmed the presence of VZV in 36 (57%) patients and HSV in 27 (43%) patients. The average age at presentation in the VZV group was 49 years and in the HSV group was 33 years. There was no statistically significant difference between HSV and VZV in laterality, gender distribution, or prior duration of symptoms or follow-up. Eighteen of 36 patients (50%) with VZV retinitis were HIV+ at the time of presentation, while 4 of 27 (15%) with HSV retinitis were HIV+. Eighteen (50%) of the patients with VZV-retinitis had bilateral disease, compared to 5 (19%) with HSV-retinitis (p=0.03). At initial presentation, 23 of 54 (42%) VZV-retinitis eyes had retinitis involving Zone 1, compared to 5 of 33 (15%) HSV-retinitis eyes (p=0.06). Treatment strategies varied. Seventy percent of all patients received intravenous therapy. Seventy-five percent of all patients received intravitreal injections. Eighty-nine percent of injections included both foscarnet and gancicolovir. For VZV retinitis, 13% of eyes that underwent laser demarcation subsequently developed RD, while 53% of eyes without demarcation developed RD (p=0.01). For HSV retinitis, 36% of eyes that underwent laser demarcation subsequently developed RD, while 67% of eyes without demarcation developed RD (p=0.07). The presenting vision was not statistically different between eyes that underwent demarcation and those that did not (p=0.17). The difference in final VA was statistically significant (p=0.004) between the two groups: laser demarcation (logMAR 1.38) and no laser demarcation (logMAR 2.33).
Conclusions: :
In this retrospective study, patients with PCR-confirmed VZV retinitis were more likely to have HIV at presentation, bilateral disease, and zone I involvement relative to HSV. Laser demarcation was associated with a statistically significantly decreased incidence of RD and improved final VA. Prophylactic laser demarcation is likely beneficial in the management of HSV and VZV retinitis.
Keywords: retinitis • laser • herpes simplex virus