Acute Retinal Necrosis: Presenting Characteristics and Clinical Outcomes in a Cohort of Polymerase Chain Reaction-Positive Patients

Fulminant bilateral acute retinal necrosis complicated with secondary herpes simplex type-1 viral encephalitis: A case report

RATIONALE

Acute retinal necrosis (ARN), which is characterized by peripheral necrotizing retinitis, severe retinal arteritis, and progressive inflammatory reaction in the vitreous and anterior chambers, has been reported in cases with herpes simplex encephalitis (HSE). It is a relatively rare complication secondary to HSE. However, cases presented with viral encephalitis following ARN were seldom reported.

PATIENT CONCERNS

A 43-year-old immunocompetent male patient manifested the aforesaid reverse situation. He developed HSE following 3-day systemic steroid therapy for abrupt ocular pain and rapidly decreased visual acuity, which was later diagnosed as ARN. Polymerase chain reaction (PCR) analysis of vitreous specimen verified herpes simplex virus-1 (HSV-1) infection.

DIAGNOSIS

HSE associated with ARN.

INTERVENTIONS

The patient was treated with intravenous acyclovir (500 mg every 8 h) for 21 days. A pulse of intravenous methylprednisolone, 500 mg/d for 5 days was given as an anti-inflammatory therapy, followed by prednisone taper.

OUTCOMES

The patient's neurological symptoms got improved very soon after the therapy, but his vision acuity remained no perception of light in both eyes.

LESSONS

The present case indicates that ARN can also be a risk factor for HSE. Once ARN was suspected, corticosteroid should be applied with caution and in combination with antiviral treatment to avoid progressive duplication of virus and its spread to the brain.

Acute retinal necrosis in a patient with remote severe herpes simplex encephalitis

A 60-year-old man with a history of severe herpes simplex virus type 1 (HSV-1) encephalitis 2 years prior presented with acute onset of visual loss in the left eye. Dilated funduscopic examination showed retinitis and occlusive vasculitis with retinal necrosis. PCR of the vitreous fluid was positive for HSV-1, and he was diagnosed with acute retinal necrosis (ARN) due to HSV-1. The patient was treated with intravenous acyclovir and intravitreous foscarnet for 2 weeks, followed by high dose oral valacyclovir for 2 weeks. He was subsequently placed on planned life-long suppressive valacyclovir. His case demonstrates that acute visual loss concomitant with or subsequent to HSV-1 encephalitis warrants suspicion of ARN. Prompt therapy with effective antiviral medication is necessary to reduce the risk of sight-threatening complications. Chronic suppression with oral antiviral therapy after ARN is recommended to prevent involvement of the contralateral eye, though there is no consensus on the duration and dosage of antivirals.

Acute Retinal Necrosis Multicenter Case Series: Prognostic Indicators and Treatment Outcomes

Purpose:

The purpose of this article is to report the prognostic associations of acute retinal necrosis (ARN), determine the diagnostic utility of aqueous vs vitreous polymerase chain reaction (PCR), and describe outcomes of antiviral, corticosteroid, antithrombotic, and laser retinopexy treatment.

Methods:

A retrospective, nonrandomized case series was conducted. Primary outcomes included final visual acuity (VA), severe VA loss (≥1.00 log of the minimum angle of resolution [logMAR] [Snellen equivalent, <20/200]), and retinal detachment (RD).

Results:

Fifty eyes of 46 patients were diagnosed with ARN. Varicella-zoster and herpes simplex viruses were the viral etiology in 29 and 16 eyes, respectively. Five were diagnosed on clinical criteria. Intravenous acyclovir was administered in 90% of eyes. Neither induction therapy for ≥13 days ( P = .692) nor intravitreal medication ( P = .203) decreased the incidence of severe vision loss. Maintenance antiviral medication was administered in 96% of eyes (50% received >13 weeks). At final follow-up, 40% of eyes had severe vision loss (range, –0.08 to +3.0 logMAR [Snellen, 20/17-no perception of light]). Forty-six percent developed RD. Relative afferent pupillary defect (RAPD), zone and extent of retinitis, and RD were prognostic of final VA. Antithrombotic therapy was administered in 25/50 eyes and was associated with lower incidence of severe VA loss ( P = .027) and better final VA ( P = .040). Laser retinopexy was performed in 40% of eyes with no significant effect on RD incidence ( P = .901) or severe VA loss ( P = .451).

Conclusions:

ARN has a high incidence of RD and poor visual outcomes. Aqueous humor PCR is the first-line diagnostic investigation. Prognostic indicators include RD, RAPD, zone, and extent of retinitis. Induction antiviral medication is appropriate for at least 12 days. Antithrombotic medication is associated with improved outcomes. Laser retinopexy does not reduce the incidence of RD.