First-line management of necrotizing herpetic retinitis by prioritizing the investigation of immune status and prognostic factors for poor visual outcomes

Purpose To review management, treatment, and outcomes of patients with necrotizing herpetic retinitis (NHR) to propose an algorithm for first-line management of NHR. Methods Retrospective evaluation of a series of patients with NHR at our tertiary center between 2012 and 2021 using demographic, clinical, ophthalmologic, virological, therapeutic, and prognostic characteristics was performed. Patients were classified by NHR type: acute retinal necrosis (ARN), progressive outer retinal necrosis (PORN), cytomegalovirus (CMV) retinitis. Results Forty-one patients with NHR were included: 59% with ARN, 7% with PORN, and 34% with CMV retinitis. All patients with CMV retinitis and PORN were immunocompromised versus 21% of patients with ARN. CMV infection was found in 14 (34%) patients, varicella zoster virus infection in 14 (34%) patients, herpes simplex virus type 2 infection in 8 (20%) and type 1 infection in 5 (12%) patients. Intravenous antiviral therapy was received by 98% of patients and intravitreal antiviral injections by 90% of patients. The overall complication rate during follow-up was 83% of eyes. Most frequent complications were retinal detachment (33% eyes) and retinal break (29% eyes). Prognostic factors for poor visual outcomes were pre-existing monocular vision loss in contralateral eye among 17% of patients, bilateral NHR in 17% of patients, posterior pole involvement in 46% of eyes, and involvement > 2 retinal quadrants in 46% of eyes. Conclusions The visual prognosis of patients with NHR remains poor. Prompt investigation of immune status and presence of factors justifying intravitreal antiviral injections must be prioritized to initiate and adapt management while awaiting causative virus confirmation.