Isolated Intraocular Jarisch-Herxheimer Reaction Following Treatment for Syphilitic Chorioretinitis.

A 39-year-old male patient presented with grossly reduced vision in the left eye for the past three months. Fundus evaluation revealed multiple discrete grayish-white deep chorioretinal lesions in the macular area. An optical coherence tomography (OCT) scan in the affected area was normal. Following investigations, a specific diagnosis of syphilitic macular chorioretinitis was made. A repeat OCT on day eight revealed cystic macular edema, consistent with a Jarisch-Herxheimer reaction (JHR). He was started on oral prednisolone in tapering doses and followed up till resolution. The ocular correlates of JHR are rare, and physicians should be aware of the potential of this phenomenon.