Retinal dysfunction of syphilitic outer retinopathy.

Purpose: We present our findings in two cases of retinal dysfunction caused by syphilitic outer retinopathy. CASE 1: A 59-year-old man visited our clinic complaining of blurred vision in his left eye. Optical coherence tomography (OCT) demonstrated an absence of the ellipsoid zone (EZ) in the left eye. A round yellowish-white lesion was observed in the posterior pole of the left fundus. Fundus autofluorescence (FAF) showed hyperfluorescent areas in the posterior pole of both fundi although no specific ophthalmoscopic findings were seen in the right eye. The amplitudes of the LA 3.0 1 Hz and LA 3.0 30 Hz ERG responses were reduced with better preservation of the rod responses. Based on a strong positivity to the rapid plasma reagin (RPR) assay and the Treponema pallidum hemagglutination (TPHA) test, he was diagnosed with syphilitic outer retinopathy and treated with systemic antibiotics. The treatment resulted in a restoration of the retinal structures and cone function. CASE 2: A 47-year-old man was referred to our clinic complaining of reduced vision in both eyes. Although the ocular fundus appeared normal, FAF showed a diffuse hyperfluorescent area in the posterior pole and multiple hyperfluorescent spots. Indocyanine green angiography showed multiple confluent areas of hypofluorescence. OCT demonstrated irregular EZs in both eyes. The amplitudes of the LA 3.0 1 Hz and LA 3.0 30 Hz ERG responses were slightly reduced with prolonged implicit times. These findings are comparable to the findings in patients with multiple evanescent white dot syndrome. However, the strong positivity to the RPR and TPHA tests led us to diagnose the patient with outer retinopathy caused by syphilis. Systemic administration of antibiotics resulted in the restoration of the retinal structures and retinal function.
Conclusions: Syphilitic outer retinopathy affected the retinal structures and function that can be restored by antibiotic treatments.