A 29-year-old man reported that he had night blindness in both eyes for about 1 year. He had no family history of retinal disease. At the initial examination, his visual acuity was 20/20 in both eyes, and the intraocular pressure was 15 mmHg in right eye and 13 mmHg in left eye. Slit-lamp examination did not show cells or flare in the anterior chamber, rubeosis iridis, or vitreous opacities. There were no obvious inflammatory cells in the vitreous. Ophthalmoscopy showed neovascularization on both optic discs (Fig. 1A). White spotted lesions were found throughout the retina, however no pigmentary deposits or attenuation of the retinal vessels was detected (Fig. 1B). Fundus autofluorescence (FAF) showed hypo-autofluorescence suggesting atrophy of the retinal pigment epithelium (RPE), and the sites of the hypo-autofluorescence atrophy matched the retinal white-spotted lesions (Fig. 1C). Optical coherence tomography (OCT) showed a shortening of the length of the ellipsoid zone (EZ), slight nodular elevation of the foveal EZ, thinning of the outer nuclear layer and punctate hyperreflectivity of the choroid (Fig. 2A, B). Fluorescein angiography (FA) showed leakage from the neovascular tissue, nonperfused areas in the peripheral retina, and window defects indicating the sites of the RPE atrophy (Fig. 3A, B). Electroretinography (ERG) showed that the dark-adapted (DA) 0.01 ERGs were non-recordable from both eyes (Fig. 4A). The amplitudes of the DA 3.0 ERGs were markedly reduced (Fig. 4C). The amplitudes of both the light-adapted (LA) 3.0 1 Hz and 30 Hz ERGs were also reduced (Fig. 4E, G), but were relatively better preserved than the DA ERGs.
No abnormalities were found on the chest X-rays and ultrasound evaluations of the carotid artery. Cutaneous eruptions were not observed. Systemic workup including antinuclear antibodies, antidouble-stranded DNA, antineutrophilic cytoplasmic antibodies, rheumatoid factor, IgG4, angiotensin-converting enzyme serum lysozyme, T-SPOT, Mycoplasma pneumoniae antibody, toxoplasmosis IgG and IgM, Epstein-Barr virus-viral capsid antigen IgG and IgM, IgG and IgM of varicella-zoster virus and herpes simplex virus, angiotensin converting enzyme, lysozyme, myeroperoxidase and proteinase3 ANCA, antiSS-A/Ro, antiSS-B/La, antiU1-ribonucleoprotein antibody, and soluble interleukin-2 receptor were all unremarkable. The patient had a mildly elevated C-reactive protein.
The serological test also showed an elevated rapid plasma reagin value to 512 RU (normal value: <1 RU), and a T. pallidum hemagglutination value of 40960 TU (normal value: <80 TU). He was diagnosed with syphilis. He tested negative for HIV, gonorrhea, and chlamydia. After the diagnosis was confirmed, he was treated with 1500 mg/day of oral amoxicillin for 10 months and with 30 mg/day of oral prednisolone for 6 weeks.
Intravitreal injection of bevacizumab (IVB) were performed on both eyes with the start of oral treatment, and the optic disc neovascularity quickly regressed ophthalmoscopically. Because residual neovascularity was confirmed by OCT angiography (OCTA) and FA, panretinal photocoagulation (PRP) was performed. A small number of vitreous hemorrhages and mild macular edema were observed during the recovery period, however both abnormalities were resolved and no additional treatment was given.
One year after the initial treatment, the visual acuity was maintained at 20/20, and FA demonstrated that the ischemic changes were resolved (Fig. 3C).
OCT revealed that length of EZ was slightly prolonged, and the nodular elevations of foveal EZ were improved (Fig. 2).
OCTA showed a regression of the optic disc neovascularization after the IVB and further regression after the PRP (Fig. 3D-F). No significant changes were seen in the FAF images (Fig. 1C). The ERG waveforms showed no obvious improvement which indicated that the retinal damage was probably permanent (Fig. 4).