Clinical and Virological Characteristics and Prognostic Factors in Viral Necrotizing Retinitis

Abstract

Purpose: Describe the clinical and virological characteristics of viral necrotizing retinitis (VNR) and assess its prognostic factors. Methods: Retrospective study (Pitié Salpêtrière Hospital, Paris) of consecutive VNR patients diagnosed and monitored by qPCR on aqueous humor between 2015 and 2019. All patients received induction therapy with intravenous +/− intravitreal injections (IVI) of antivirals. Results: Forty-one eyes of 37 patients with a mean age of 56 years were included. Involved viruses were VZV (44%), CMV (37%) and HSV2 (19%). Acute retinal necrosis represented 51%, progressive outer retinal necrosis 12% and CMV retinitis 37% of eyes. Forty-six percent of patients were immunocompromised. Median BCVA was 0.7 LogMAR at baseline and 0.8 LogMAR after an average of 14.1 months. VNR bilateralized in 27% of cases after 32 months. Retinal detachment (RD) occurred in 27% of cases after a mean duration of 98 days. Factors associated with a “poor BCVA” at 1 month were: advanced age, low baseline BCVA, high vitritis grade and viral load (VL) at baseline and the “slow responder” status (i.e., VL decrease <50% after 2 weeks of treatment). Factors associated with RD were: advanced age, immunocompetence, low baseline BCVA, high vitritis grade at baseline and use of ≤5 IVIs. Conclusions: Clinical factors including advanced age, immunocompetence, low BCVA and high vitritis grade at baseline were associated with a poor prognosis. New virological factors were predictive of a poor outcome: high baseline VL and the “slow responder” status. Sequential intraocular fluid sampling might help prognosticate the outcomes of VNR.

Keywords: CMV; HSV; VZV; outcome; prognosis; retinal detachment; viral load; viral necrotizing retinitis.

Figure 1

Viral load evolution in rapid and slow responders according to each virus. Each virus is presented with a different color. Each eye is represented by a single curve. Slow and rapid responders correspond respectively to eyes with a viral load decrease lower or greater than 50% (versus baseline) after 2 +/− 1 weeks of intravenous antiviral treatment. On the X axis, viral load measured at the 1st visit (baseline = 0) and after 1, 2 and 3 weeks. On the Y-axis, viral load expressed in the logarithm of international units per milliliter. HSV: Herpes simplex virus; VZV: Varicella zoster virus; CMV: Cytomegalovirus.

Figure 2

Evolution of visual acuity according to each virus. X-axis: time in months. Y-axis: BCVA (best-corrected visual acuity) in LogMAR. The red line represents the mean BCVA, the black line represents the median BCVA, the n displayed at the bottom corresponds to the number of evaluated eyes at each timepoint. Single points represent an extreme value < Q1-1.5*Interquartile range or > Q3+1.5*Interquartile range. HSV: Herpes simplex virus; VZV: Varicella zoster virus; CMV: Cytomegalovirus.