Acute Retinal Necrosis: Poor Visual Outcomes and High Risk of Retinal Detachment in a Case Series from Two Referral...

Acute retinal necrosis (ARN) is a severe and vision-threatening complication of herpesvirus infection, characterized by rapid progression and significant visual morbidity. While intravenous acyclovir remains the cornerstone treatment, adjunctive therapies such as intravitreal antivirals and surgical interventions may reduce complications.

This retrospective study analyzed 18 ARN cases from two reference hospitals in São Paulo, Brazil, over a seven-year period (2017-2024).

The cohort primarily consisted of female patients (57.9%), with a mean age of 51.4 years. The majority (83.3%) were immunocompetent and 94.4% had unilateral initial manifestation. Retinal detachment was the most common complication, occurring in 50% of cases, followed by vitreous haze (11.1%) and phthisis bulbi (11.1%). Visual acuity (VA) outcomes were generally poor, with 61.1% of patients experiencing deterioration, 27.8% showing improvement, and only 11.1% maintaining their initial VA. The mean initial VA was < 20/200, emphasizing the severity of disease presentation and the consequences of delayed diagnosis and referral.

In this case series, ARN occurred predominantly in immunocompetent individuals and carried a high risk of retinal detachment, further complicating visual prognosis. The high rate of retinal detachment observed, despite standard antiviral therapy, raises the possibility that delays in diagnosis or referral may have influenced outcomes. Further research is warranted to optimize treatment protocols for this rare yet devastating condition, particularly in mitigating the risk of retinal detachment and improving long-term visual outcomes.