Retinal Vasculitis Is Principally a Single-Organ Vasculitis of the Eye
Eales disease is a well-known form of vasculitis (prevalent in the Indian subcontinent), where inflammation is limited to retinal veins.3 Despite such well-documented literature, retinal vasculitis does not find a mention as SOV in major nomenclature systems (Chapel Hill,2 2012), even though its importance has been highlighted in other updates.1 Previously, we have discussed this lacuna and have aligned retinal vasculitis in the perspective of modifications suggested by the revised Chapel Hill nomenclature system (CHNS).3
In 2015–2016, we prospectively studied consecutive patients diagnosed as having retinal vasculitis at our center (unpublished data). Retinal vasculitis was defined as presence of signs of active or resolved retinal vascular inflammation, as visualized on fundus examination of the eye. These signs included cuffing or sheathing of retinal vessels with inflammatory exudates and inflammatory occlusive retinal vasculitis, with or without the sequelae of vasculitis (like new vessels). Fluorescein angiography was done for all patients to confirm clinical findings. Patients with primary diagnosis of uveitis or any other ocular disease were excluded from this study. Tailored investigations and organ-specific consultations were carried out based on the clinical history, examination, and suspected diagnosis to rule out infective causes, systemic disease, and systemic vasculitis. Blood count, erythrocyte sedimentation rate, Mantoux test, and chest x-ray were obtained for all the patients. The primary outcome measure was to identify the pattern of retinal vasculitis in the perspective of the revised CHNS and identify the prevalence of SOV in the study population.2
Two hundred patients were included for analysis. The most common symptom on presentation was diminution of vision (52%), followed by visualization of floaters (46%). Incidental diagnosis was made in 2% of patients. The disease was diagnosed for the first time in 53.27% of patients (active or sequelae), 35.18% had recurrent disease, and 11.56% cases had healed vasculitis without any sequelae. Median duration of symptoms was 2.75 months in patients with newly diagnosed disease. Of the 200 patients included, 145 (72.5%) had bilateral involvement. Systemic vasculitis was identified in 5 patients (2.5%), whereas vasculitis associated with systemic disease (infectious and noninfectious) was identified in 11 patients (5.5%) (Fig.). Thus, 184 patients (92%) were identified to have SOV. During follow-up (minimum 1.5 years), only 1 of these patients was reclassified to have vasculitis associated with systemic disease (tuberculosis). Details of diagnosis are presented in Table 1.
The Chapel Hill nomenclature system considers SOV to be “Vasculitis in arteries or veins of any size in a single organ that has no features that indicate that it is a limited expression of a systemic vasculitis.”2 Literature is abundant in studies (conducted both before and after modified CHNS) describing retinal vasculitis as idiopathic or primary or localized to the eye.4–13 A summary of these studies is presented in Table 2. In the majority of these studies, including ours, retinal vasculitis has presented as SOV (up to 90%). Even in those studies where SOV is not the most common presentation, a sizable number of patients have been found to have vasculitis localized to the eye.