May 31, 2019 Conference
Systemic inflammatory disorders can manifest as uveitis, and in theory, both eyes should be equally susceptible. The development of recurrent unilateral iritis raises suspicion about the possibility of an underlying viral etiology as these entities (and specifically the Herpes viruses) establish latency within anatomic structures that would predispose to recurrences within the same eye (ie. trigeminal ganglion, ciliary ganglion, corneal endothelium, vascular endothelium). Aside from laterality, the Herpes viruses often have other ocular findings that may alert the clinician to the presumed diagnosis including: raised intraocular pressure (38-90% of eyes), corneal scars and/or opacities (33% of eyes), patchy or sectoral iris atrophy (10-88% of eyes), posterior synechiae (38% of eyes)1. Although the laterality of recurrent inflammatory events may be suggestive of a viral condition, this factor alone is not diagnostic. Rosenbaum et al reported a series of patients with HLA-B27 associated uveitis. The initial event occurred in the right eye in 52.5% of patients and in the left 44% of patients, but the difference between involvement right versus left was not statistically significant. Interestingly, 69.4% of subsequent episodes occurred in the same eye affected previously2. In summary, laterality along with other associated clinical features may suggest a viral diagnosis, but the manifestation of recurrent, monocular iritis does not exclude the possibility of an autoimmune disorder .