Comparison of the ocular characteristics of anterior uveitis caused by herpes simplex virus, varicella-zoster virus, and cytomegalovirus

Abstract
To compare the clinical characteristics of anterior uveitis (AU) caused by herpes simplex virus (HSV), varicella-zoster virus (VZV), or cytomegalovirus (CMV). The medical records were reviewed of 46 patients whose diagnoses were based on their clinical characteristics [e.g., unilateral involvement, presence of keratic precipitates (KPs), and elevation of intraocular pressure (IOP)] and on PCR detection of herpes virus DNA in the aqueous humor. The demographics, chief complaints, and clinical characteristics of the three types of herpetic AU were compared. Of the 46 patients with AU, eight had HSV-AU, 20 had VZV-AU, and 18 had CMV-AU. HSV-AU and VZV-AU shared common features, i.e., a relatively acute disease process and the presence of large KPs. Among the three groups of patients, the characteristic features of those with VZV-AU were severe intraocular inflammation, as shown by severe aqueous flare, highest viral load in the aqueous humor, and presence of segmental iris atrophy. In comparison, patients with CMV-AU had the mildest intraocular inflammation, lowest corneal endothelial cell density, and highest IOP. Although the AU caused by each of the three types of herpes viruses has a number of common features, each disease also has distinct features that should facilitate an accurate diagnosis.