Acute retinal necrosis: a case series with emphasis on associated immune dysfunction and clinical outcomes

Authors: Delphine Gobert, Justine Rheault, Simon Couture, Isabelle Schmit. Département d'Ophtalmologie et ORL-Chirurgie cervico-faciale, Université Laval.

Author Disclosure Block: D. Gobert: None. J. Rheault: None. S. Couture: None. I. Schmit: None.

Abstract Body:

Purpose: Acute retinal necrosis (ARN) is a rapidly progressing viral necrotizing retinitis that can have devastating consequences. Although ARN has traditionally been described in immunocompetent patients, there is now evidence that ARN and other retinitis such as PORN and CMV retinitis could represent a clinical spectrum of necrotizing herpetic retinopathies, in which the severity depends on the patient's immune state. The goal of this case series was therefore to determine if the immune status of patients who developed ARN can influence their visual prognosis.

Study Design: Retrospective observational case series.

Methods: All the charts of patients that were treated for ARN in our center between January 2010 and December 2019 were identified. Clinical features including demographic information and pertinent medical history were collected as well as complete ocular examination findings. Primary outcomes included final visual acuity and incidence rate of retinal detachments.

Results: The charts of 18 patients were included. In this cohort, 12 patients (66.7 %) had associated immune dysfunction, including 5 patients (27.8%) with a history of malignancy, 2 patients (11.1 %) on immunosuppressants and 5 patients (27.8 %) that were considered to have relative immune dysfunction due to other co-morbid systemic diseases such as diabetes or malignancy that was only diagnosed after they had developed ARN. In patients with immune dysfunction, VZV was identified as the causative agent in 66.67% of cases (8 patients), whereas HSV1 was identified in 33.33% of cases (4 patients). At presentation, the retinitis involved more quadrants in immunocompetent patients (83.33% of patients with 3 or more quadrants involved) than in patients with immune dysfunction (41.67% of patients with 3 or more quadrants involved). However, incidence of retinal detachment was slightly higher in patients with immune dysfunction (58.33% of patients vs. 50% of immunocompetent patients). Visual acuity (VA) improved in both groups with treatment and final VA was not statistically different between immunocompetent patients and patients with immune dysfunction (1.00 ± 0.23 logMAR vs. 1.25 ± 0.42 logMAR, p=0.7).

Conclusions: Although not associated with significantly poorer outcomes, ARN might occur in a previously underrecognized proportion of patients with associated immune dysfunction.