# Necrotizing Herpetic Retinopathy: A Case of Delayed Acute Retinal Necrosis Presentation in a Patient With Uncontrolled Diabetes Mellitus and Complications

## TL;DR

A patient with uncontrolled diabetes and ARN experienced severe vision loss due to retinal detachment, highlighting the importance of early diagnosis.

## Contribution

This case report highlights the rare interplay between uncontrolled diabetes, ARN, and retinal detachment, emphasizing the need for early diagnosis.

## Key findings

- The patient presented with ARN and developed severe retinal detachment despite treatment.
- Uncontrolled diabetes and tobacco use may have contributed to the patient's poor prognosis.
- There is a lack of existing research on the combined effects of diabetes, ARN, and tobacco use.

## Abstract

Necrotizing herpetic retinopathy is a term used to describe two similar yet different forms of retinopathy - acute retinal necrosis (ARN) and progressive outer retinal necrosis (PORN), which can both present similarly with eye pain and/or vision loss stemming from inflammatory and necrotic retinal changes caused by members of the Herpesviridae family. This case presentation involves a patient with ARN, which has a multifocal pathogenesis, creating diffuse necrosis that over time coalesces and increases the risk of rhegmatous retinal detachment.

We report the case of a 56-year-old male with uncontrolled insulin-dependent diabetes mellitus complicated by retinopathy and heavy tobacco use who presented with nonspecific symptoms of left eye redness, burning ocular pain, and blurred vision with lateral field vision loss for two weeks. Thorough dilated fundus examination with retinal imaging identified 360-degree retinal necrosis extending to the periphery, mild retinal hemorrhages, and moderate disk edema. Serology was found to be positive for herpes simplex virus (HSV)-1 IgG, which did not confirm ongoing infection as HSV-1 IgM was negative. Other testing, including HSV-2 IgG, human immunodeficiency virus (HIV)-1 and HIV-2 screening antibody, QuantiFERON Gold (Qiagen, Hilden, Germany), cytomegalovirus (CMV) IgG and IgM, and polymerase chain reaction (PCR) for toxoplasmosis, was negative. Intravitreal fluid sampling was negative for HSV-1 and 2 DNA by PCR, although CMV and varicella zoster virus (VZV) were not tested due to lab limitations. The patient was placed on standard ARN treatment with IV acyclovir three times a day, ophthalmic prednisolone drops two to four times a day, and a single dose of intravitreal ganciclovir injection. At the time of discharge, associated symptoms had resolved with minimal vision improvement. Follow-up was complicated by a total retinal detachment leading to complete loss of vision in the left eye.

Due to complicated compounding factors found in our patient, many factors may have influenced his severe complications and poor prognosis following discharge, despite appropriate treatment. It has been shown that uncontrolled diabetes can make individuals immunocompromised and predispose them to many infectious diseases. It is possible that this could be a risk factor for our patient. Although ARN is associated with retinal detachment, we are not able to exclude underlying diabetic retinopathy and vascular atherosclerosis related to tobacco dependence as contributing factors. Although there has been some evidence of a commonality between ARN and patients with pre-existing diabetes mellitus, there is no current research found to describe the interplay between uncontrolled diabetes with diabetic retinopathy, continued tobacco use, and the sequential development of ARN.

This case report discusses a patient presenting with classic symptoms of a unique retinal pathology, ARN, complicated by severe retinal detachment. The goal of this case report is to bring awareness of a rare disease to assist providers in making an efficient diagnosis to prevent vision loss.