Definition Urayama and colleagues1 published the first six instances of an apparently novel condition with acute necrotizing retinitis, vitritis, retinal arteritis, choroiditis, and late-onset rhegmatogenous retinal detachment in 1971. In 1978, Young and Bird2 described two comparable cases and coined the acronym BARN for the syndrome (bilateral acute necrosis syndrome). The disease was dubbed acute retinal necrosis syndrome, or ARN syndrome, after the discovery of unilateral and asynchronous bilateral instances. The start of episcleritis or scleritis, periorbital discomfort, and anterior uveitis, which may be granulomatous or stellate in appearance, are all symptoms of acute retinal necrosis syndrome. Reduced vision due to vitreous opacification, necrotizing retinitis, and, in certain cases, optic neuritis or neuropathy follows. The retinitis manifests itself as deep, multifocal yellow-white patches that start in the peripheral fundus (Figs 88.1, 88.2) and subsequently become concentrically confluent and expand toward the posterior pole (Figs 88.388.5); the macula is frequently spared. Perivascular hemorrhages, sheathing, and terminal thrombi obliteration of arterioles are all signs of active vasculitis. The active phase of retinitis typically lasts 46 weeks. 38
Akira Urayama defined acute retinal necrosis (ARN) as a clinical illness characterized by an acute unilateral panuveitis, retinal periarteritis, and necrotizing retinitis. This illness process was found to occur in persons who were otherwise healthy. Forster and colleagues proposed the term "progressive outer retinal necrosis," or PORN, to describe a condition that affects immunocompromised people in 1990. They identified an infectious retinitis with little intraocular inflammation, major involvement of the outer retina, and involvement of the posterior pole linked with recent cutaneous zoster infection. Although our understanding of the disease has progressed since then, these characteristics have remained constant. Rapidly progressive herpetic retinal necrosis is another name for PORN (RPHRN). [1] PORN has a significantly lower rate of ocular inflammatory reaction than ARN. Etiology
Although there are a few case reports of CMV PORN in the ophthalmologic literature, CMV is a less common cause of progressive outer retinal necrosis. A 37-year-old Indian man with a clinical diagnosis of PORN had a CMV-positive PCR but negative PCR for HSV and VZV, according to a 2002 report. 5 Our patient was started on HAART (emtricitabine/tenofovir and raltegravir) as well as double strength sulfamethoxazole and trimethoprim while in the hospital. He was closely monitored, and by the time he was discharged on day 14, his vision had stabilized at 20/80. (See Figure 5). Despite repeated attempts by the Infectious Disease Department and the Wills Eye Retina Service to contact the patient, he did not return for additional follow-up visits. REVIEW
Acute varicella retinitis/choroiditis in children, as well as chronic choroiditis or non-necrotizing retinal vasculitis in adults, are examples of viral posterior uveitis that can show as patchy, solitary, or numerous retinitis patches.
Chikungunya retinitis[4042] is a type of herpetic or CMV retinitis that is diagnosed by a history of chikungunya sickness and the identification of specific antibodies to the virus in blood or intraocular fluid. It's usually self-limiting, and acyclovir or intravitreal ganciclovir have been reported to help, albeit they're not specific.
