# Birdshot Chorioretinopathy in a Patient on Tocilizumab for the Treatment of Giant Cell Arteritis

## TL;DR

A patient with giant cell arteritis on tocilizumab developed asymptomatic Birdshot chorioretinopathy, a rare eye condition, with no prior reported cases of this combination.

## Contribution

First reported case of Birdshot chorioretinopathy in a patient with giant cell arteritis treated with tocilizumab.

## Key findings

- The patient had asymptomatic BSCR lesions while on tocilizumab for GCA.
- No prior cases of co-occurring GCA and BSCR were found in the literature.
- Tocilizumab may have suppressed BSCR symptoms due to its immunosuppressive effects.

## Abstract

Birdshot chorioretinopathy (BSCR) is a presumed autoimmune disease of the eye affecting mostly middle-aged women and typically associated with the HLA-A29 genetic haplotype. Presenting symptoms include blurred vision, nyctalopia, and floaters. Classic fundus findings are multiple, bilateral, creamy, oval lesions around the optic nerve, mostly nasal and inferior to the disc. Fluorescein/indocyanine angiography, optical coherence topography, and fundus autofluorescence can be used for diagnosis and disease monitoring. Here, we present a case of a patient with giant cell arteritis (GCA) on tocilizumab who presented with asymptomatic BSCR lesions in both eyes. Both GCA and BSCR have T cell lymphocyte–mediated inflammation and are treated with corticosteroids. In our case, the patient was on a steroid-sparing agent, which may have suppressed symptoms of BSCR. We found no other cases of a patient having both GCA and BSCR.