Acute retinal necrosis

Acute retinal necrosis: pathophysiological aspects, diagnosis, and treatment

Acute retinal necrosis (ARN) is a devastating viral infection commonly associated with varicella zoster virus (VZV) and herpes simplex virus types 1 and 2 (HSV-1, HSV-2). Typically, ARN affects individuals without immune status disorders between the ages of 50-70. In two-thirds of the cases, one-eye involvement is observed and the inflammation can be presented as panuveitis. The most characteristic clinical manifestations are vitreitis, occlusion of the retinal arterioles, and peripheral necrotizing retinitis. Retinitis presents with the appearance of deep, multifocal, yellowish-white foci, typically localized in the peripheral retina. Systemic antivirals are the first treatment of choice for ARN. The goal of the therapy is to stop the viral replication and disease progression in the affected eye, as well as to prevent involvement of the healthy eye. The other eye can be attacked in an interval of 5 days to 30 years. The visual prognosis after illness is poor. Early diagnosis and timely initiation of treatment play an important role in maintaining visual acuity and preventing the other eye from being affected.

Management Strategies of Acute Retinal Necrosis: Current Perspectives

Acute retinal necrosis is a rare yet devastating disease, with significant ocular morbidity. Over the past several decades, initial treatment regimens have shifted from intravenous antivirals requiring hospital admission to the routine use of oral antivirals with intravitreal antivirals for immediate local control. Given the rarity of this disease process and a lack of large-scale research trials, debate continues over recommended practice guidelines. In this paper, we review current diagnostic criteria and recommend a treatment algorithm based on available evidence.

Branch Retinal Artery Occlusion as a presenting sign of Acute Retinal Necrosis: a rare association

Background

Acute retinal necrosis (ARN) is a potentially blinding necrotizing viral retinitis. It starts with one or more foci and spreads circumferentially and involves the posterior pole in the later stages. Vascular occlusions such as branch retinal artery occlusion, central retinal artery occlusion, and central retinal vein occlusion may occur secondary to underlying infectious etiology such as ARN.

Findings

An elderly male patient with a history of coronary artery disease was diagnosed with branch retinal artery occlusion (BRAO) in the right eye and referred to the treating cardiologist. Few days later, he complained of diminution of vision in the left eye which made him seek another consultation when he was diagnosed to have ARN in the left eye, encroaching the posterior pole. He was investigated and treated for the same leading to minimal improvement of vision in the left eye possibly due to a delay in the starting of the anti-viral therapy.

Conclusion

We report this case to highlight that occlusive vasculopathy can be a presenting sign of an underlying infectious etiology in any age group. BRAO was a rare presenting sign of ARN in our patient. A thorough peripheral examination is recommended in order to avoid missing infectious pathologies such as ARN which starts from the retinal periphery, progresses fast, and if not managed on time may lead to permanent loss of vision.

Combination systemic and intravitreal antiviral therapy in the management of acute retinal necrosis syndrome (an American Ophthalmological Society thesis)

PURPOSE

To compare the outcomes of combination systemic and intravitreal antiviral therapy vs systemic antiviral therapy alone for treating acute retinal necrosis syndrome (ARN). We hypothesize that combination therapy might result in superior visual acuity (VA) and retinal detachment (RD) outcomes vs traditional systemic antiviral therapy alone.

METHODS

A retrospective, interventional, comparative single-center study of patients with ARN. We reviewed demographic data, herpesvirus diagnoses, polymerase chain reaction (PCR) results, VA, RD, and the use of systemic and intravitreal antiviral therapy. Outcome measures included VA improvement by 2 or more lines, severe visual loss, VA ≤20/200, and RD.

RESULTS

We studied 29 eyes of 24 patients, treated from 1987 through 2009. Mean age was 42.6 years and mean follow-up was 44.0 months. Twelve patients (14 eyes) were treated with combined systemic and intravitreal antiviral therapy and 12 patients (15 eyes) with systemic therapy alone. Kaplan-Meier survival analysis revealed that patients receiving combination intravitreal and systemic antiviral therapy were more likely to have VA improved by 2 lines or greater (P=.006). Patients receiving combination therapy also showed a decreased incidence of progression to severe visual loss (0.13/patient-years [PY]) compared to patients receiving systemic therapy alone (0.54/PY, P=.02) and had decreased incidence of RD (0.29/PY vs 0.74/PY, P=.03).

CONCLUSIONS

Combination oral and intravitreal antiviral therapy may improve visual and functional outcomes in patients with ARN. Clinicians should consider prompt administration of combination systemic and intravitreal antiviral therapy as first-line treatment for patients with clinical features of ARN.

Ocular Findings in Japanese Patients with Varicella-Zoster Virus Infection

PURPOSE

To examine ocular findings in Japanese patients with varicella, herpes zoster ophthalmicus, and acute retinal necrosis.

METHODS

A retrospective study was conducted. Information on the ocular, cutaneous, systemic, and virologic findings on pediatric and adult patients was obtained from medical records.

RESULTS

A total of 77 (45 male and 32 female) patients were enrolled in the study: 4 children had varicella, 68 adults had herpes zoster ophthalmicus, and 5 adults had acute retinal necrosis. Children with varicella had eruptions on the eyelid. Patients with herpes zoster ophthalmicus had eruptions, conjunctivitis, keratitis, iridocyclitis, and other findings. Patients with acute retinal necrosis had intracameral cells and retinal lesions. Some patients with herpes zoster ophthalmicus had malignancy, type 2 diabetes mellitus, or other disease. One pregnant woman developed acute retinal necrosis shortly after varicella infection. A total of 48% of patients with negative Hutchinson sign had ocular lesions, while all patients with positive sign showed ocular lesions. Patients with varicella and herpes zoster ophthalmicus had good visual acuity at the last visit. Some patients with acute retinal necrosis had poor visual acuity at the last visit.

CONCLUSIONS

Patients with varicella, herpes zoster ophthalmicus, and acute retinal necrosis had several ocular complications. Some patients with acute retinal necrosis had poor visual outcomes. Ophthalmologists should be aware that acute retinal necrosis may develop shortly after varicella infection.

Diagnosis and management of the acute retinal necrosis (ARN) syndrome

The acute retinal necrosis (ARN) syndrome represents a specific pattern of clinical presentation for certain herpes virus infections in the posterior segment of the eye. The classically described triad of the ARN syndrome consists of (1) an arteritis and phlebitis of the retinal and choroidal vasculature, (2) a confluent, necrotizing retinitis that preferentially affects the peripheral retina, and (3) a moderate to severe vitritis. Anterior segment inflammation, optic neuritis, and late retinal detachment are also common features of this disorder. Definitive evidence now implicates at least two members of the herpes virus family; varicella zoster virus and herpes simplex virus as causative agents. This paper summarizes the clinical presentation, as well as the currently recommended treatment regimen for the ARN syndrome, highlighting recent advances that have resulted in a significant improvement in the visual prognosis for affected patients.

Acute retinal necrosis syndrome presenting with papillitis and arcuate neuroretinitis

Acute retinal necrosis (ARN) syndrome is a diffuse uveitis characterized by a peripheral necrotizing retinitis and retinal vasculitis. The authors document and discuss a case of ARN syndrome that initially presented with remarkable changes in the peripapillary retinal nerve fiber layer that they have termed arcuate neuroretinitis. These changes consisted of a well-defined arcuate band of retinitis paralleling the course of a parafoveal nerve fiber bundle. Evaluation of serial serum antibody titers suggests HSV-2 as a possible causative agent in this unique presentation of ARN syndrome.

A case of frosted branch angiitis

We report a case of frosted branch angiitis in a 16-year-old-girl. She noted a sudden and severe visual disturbance in both eyes, without other systemic symptoms. Diffuse retinal oedema and unusual sheathing of retinal veins were characteristic in both fundi. Fluorescein angiography showed no occlusion of the sheathed retinal veins, but some paravenous extravasation of dye was found in the late phase. With high doses of systemic corticosteroids her fundi and visual acuity improved greatly, though the vessels continued to show severe narrowing. At three months the pattern visually evoked cortical potentials were found to be normal, while flash electroretinograms were absent. No systemic abnormality has been found to explain the aetiology of this condition.

Varicella zoster virus is a cause of the acute retinal necrosis syndrome

We studied two blind eyes enucleated during the active phase of the acute retinal necrosis syndrome. Both eyes showed similar histopathologic findings of necrotizing retinitis, retinal arteritis, and optic neuropathy. A virus morphologically consistent with a herpes group virus was found on electron microscopy and immunocytopathologic stains showed this virus to be varicella zoster in both cases. Varicella zoster virus was cultured from the vitreous of one of the eyes. We conclude that varicella zoster virus retinal infection is a cause of the acute retinal necrosis syndrome.

The acute retinal necrosis syndrome. Possible herpes simplex retinitis

The acute retinal necrosis (ARN) syndrome is a severe necrotic peripheral retinitis with vasculitis and vitritis. It attacks healthy people and carries a poor visual prognosis. Five patients with ARN were seen. Two showed interesting clinical features. One patient developed the ARN syndrome in both eyes but with a 14-year hiatus separating the two episodes, each being preceded by an infectious illness. A second patient had a possible recurrence of the ARN syndrome in the same eye, one year after the original episode. Each episode was preceded by an upper respiratory infection and ipsilateral vesicular skin lesions on the face. Biopsy of one lesion yielded herpes simplex virus (HSV) in culture. These associations, although not definitive, do lend support to the hypothesis that HSV may be the cause of the ARN syndrome.

Bilateral acute retinal necrosis (BARN). Identification of the presumed infectious agent

We describe histopathologic features of an enucleated eye of a patient suffering bilateral acute retinal necrosis (BARN). Retinal tissue was found focally degenerated, and the choroid massively enlarged by lymphoid-like agranular cells. An association of the disease with a viral infection could be demonstrated by (a) the presence of virus particles of the herpesvirus type in retinal tissue, (b) the transmission of the infected principle to human embryo fibroblast cultures, and (c) the visualization of CMV-antigens by immunofluorescence microscopy in such infected cultures. Slow growth of the virus in vitro and the presence of CMV-antigens after infection indicate that the herpesvirus involved in BARN was of the type CMV. On the basis of these findings we propose a guideline for therapy.