Early unilateral VZV-associated acute retinal necrosis misdiagnosed as iridocyclitis: a case report

Abstract Purpose To report a case of early unilateral VZV-associated acute retinal necrosis (ARN) which was initially misdiagnosed as iridocyclitis and progressed to retinal detachment. Case presentation A 41-year-old female patient presented with two weeks of blurry vision in the left eye and was initially diagnosed as iridocyclitis and uveitis. There was no response to topical corticosteroid therapy and her condition deteriorated with decreased vision. Examination revealed mutton-fat keratic precipitates, edematous optic disc, white sheaths of the retinal artery. Aqueous humor PCR returned positive for VZV and the diagnosis of ARN was confirmed. Treatment with systemic and topical antivirals, oral steroids, and anticoagulants led to temporary stabilization of her condition. Owing to significant vitreoretinal traction, the patient underwent left eye vitrectomy and endolaser photocoagulation. However, retinal detachment occurred in the left eye three weeks postoperatively, and the patient received another vitrectomy. Conclusion Even without prominent vitritis, ARN should be considered in the differential diagnosis when anterior chamber inflammation and retinal arteriolar involvement occurred. The combination of intravenous and intravitreal antiviral therapy with oral corticosteroids is recommended. When ARN is diagnosed at a late stage, the affected eye remains at a high risk of retinal detachment, even with appropriate treatment.