Secondary syphilis with ocular manifestations in older adults.

We describe 4 patients (age, >50 years) with secondary syphilis. All patients presented with ocular syphilis, and 2 presented with syphilis-negative rapid plasma reagin titers due to a prozone phenomenon. Three male patients reported sildenafil use. The presentation of these patients with ocular syphilis suggests the need for additional clinical studies involving older patients.