As for ocular symptoms in the patients with a definite diagnosis of HAU, more than 80% of VZV-AU and CMV-AU patients complained about ocular pain, whereas only 15% of HSV-AU patients had this symptom. There were no differences concerning redness and photophobia among these three subgroups. Unilateral involvement was observed in all these patients with a definite diagnosis of HAU, although bilateral involvement was also noted in 15 out of 274 patients with a clinical diagnosis of HAU. The median logMAR BCVA at the first visit for HSV-AU, VZV-AU, and CMV-AU eyes was 0.4, 0.7, and 1.0, respectively, and poor visual acuity was noted in VZV-AU patients or CMV-AU patients as compared with HSV-AU patients (
P = 0.006 and
P = 0.005). The increased IOP (>24 mm Hg) at the first visit was observed in more than 75% of the patients in all three subgroups, and the mean IOP in HSV-AU, VZV-AU, and CMV-AU patients was 24.2 ± 4.0, 40.6 ± 10.9, and 36.0 ± 12.2 mm Hg, respectively, showing a statistical difference among these three groups (
P < 0.001). Ciliary or mixed injection was noted in more than 60% of HSV-AU and VZV-AU patients, whereas it was observed only in 17% of CMV-AU patients. Corneal lesions manifested mainly as edema or opacity in all these subgroups without difference in frequency among them. KPs were observed in more than 60% of the affected eyes at the first visit and characterized by mutton-fat KPs almost universally toned with pigmentation. Anterior chamber cells were noted in all the patients in these 3 subgroups at first visit, and a severe inflammation (anterior chamber cells ≥2+) was more frequently noted in VZV-AU patients than in HSV-AU or CMV-AU patients (
P < 0.001 and
P = 0.001), although no difference was observed concerning the anterior chamber flare among these three subgroups. Iris stromal atrophy was observed in more than 75% of the patients in all three subgroups. It was single or multiple in number, and round, oval, or irregular in appearance. HSV-AU and VZV-AU patients usually presented as single or multiple patchy, or diffuse iris atrophy, whereas CMV-AU patients mostly displayed multifocal round, oval, or irregular iris atrophy (
Fig. 1,
Supplementary Table S2). There were no differences regarding posterior synechia and pupil deformation among these subgroups (
Table 2). The deformed pupil mostly showed a pulling appearance unlike that caused by other nonherpetic uveitis entities (
Fig. 2).