Abstract
Purpose::
In 1994 the Executive Committee of the American Uveitis Society published criteria for the diagnosis of acute retinal necrosis syndrome (ARN). The diagnosis requires: 1) one or more foci of retinal necrosis with discrete borders in the peripheral retina, 2) rapid progression of disease, 3) circumferential spread of disease, 4) evidence of occlusive vasculopathy with arteriolar involvement, and 5) a prominent inflammatory reaction in the anterior chamber AND vitreous. We present an interesting case that begs the question: is there a need to reassess the standard diagnostic criteria for ARN?
Methods::
Illustrative case report.
Results::
A 46y immunocompetent white male presented with 4d of decreased vision and pain OD. His vision was 20/100 OD, 20/25 OS. Intraocular pressures were 22 OD, 11 OS, and a right afferent pupillary defect was present. The slit lamp and dilated fundus examinations were normal OS, whereas scleral injection and 3+ white cells in the anterior chamber were seen OD. Gonioscopy revealed a normal open angle to the ciliary body band OU. Moderate disc swelling, diffuse venous engorgement and tortuosity, mild macular edema, 4 quadrants of mild intraretinal hemorrhages, and no vitritis were present OD. 3 days later, vision had dropped to hand motions OD, and large areas of retinal whitening without discrete borders were seen both posteriorly and peripherally. Many of his arterioles were sclerotic and segmented. There was no vitritis. Fluorescein angiography demonstrated large areas of nonperfusion with abrupt occlusions of arteriolar flow with vessel staining. IV methylprednisolone was initiated for treatment of a presumed noninfectious vasocclusive disease with associated anterior sclerouveitis. He had a negative systemic review of systems, and his chest x-ray and laboratory workup were unremarkable. 4 days later he was noted to have inferior retinal breaks and a decision to perform a diagnostic vitrectomy with retinal biopsy and retinal detachment repair was made. Immunostaining and PCR were positive for HSV. The patient was started on oral acyclovir and his oral prednisone was tapered. Vision OD subsequently evolved to no light perception.
Conclusions::
This patient did not have discrete borders to his areas of retinal ischemia nor did he have vitritis, two requirements for the diagnosis of ARN. Although ARN was #2 among the differential diagnoses, antiviral therapy was not initially instituted given the lack of vitritis and discrete borders to the retinal whitening. In the age of PCR, perhaps the utility of the strict criteria for the diagnosis of ARN proposed in 1994 should be revisited.
Keywords: herpes simplex virus • retinitis