Ocular Syphilis May be Overlooked When Presenting as Inflammation

Syphilis is a diagnosis frequently overlooked in initial investigations, according to a publication in the Canadian Journal of Ophthalmology. However, the disease has experienced a resurgence in the United States and in Canada in the last 20 years. Based on the findings of the Ontario-based case series, researchers are recommending syphilis be considered as a possible diagnosis for patients presenting with any type of ocular inflammation. 

The case series included data from 26 participants with ocular syphilis and focused on 5 specific cases to illustrate the various presentations of the condition. The patients’ sings uveitis, iris granuloma, retinitis, vasculitis, optic neuritis, and serous retinal detachment.

Anterior and posterior uveitis are common presentations of ocular syphilis, in addition to panuveitis. More than half of the patients presented with anterior uveitis, which can include corneal edema, keratic precipitates, hypopyon, and inflammatory cells, the report shows. While isolated intermediate uveitis is uncommon in ocular syphilis, it presents as part of panuveitis, which was the most common type of uveitis in this case study. 

Iris granuloma, while rare in ocular syphilis, was present in at least 1 case; the lesion presented with associated sentinel vessels, iris displacement, and anterior chamber (AC) reaction, and it was responsive to treatment with penicillin and topical steroids. 

The occurrence of vasculitis, as seen in 1 patient, was linked with a “ground glass” retinitis, though there is a large clinical variability for the condition. The last presentation, optic neuritis, manifests in ocular syphilis the same as in any condition, though there is an increased risk in HIV-positive patients, who are also more susceptible to syphilis. Patients with unilateral and bilateral cases of anterior and retrobulbar optic neuritis may experience a rapid loss of vision.

The researchers explain that, because syphilis must be detected via serologic testing for antibodies, its ocular manifestation may be overlooked as a diagnosis if testing is not carried out. However, ocular syphilis most commonly presents in secondary and tertiary disease and is extremely rare in primary syphilis. The study concludes that the standard treatment using penicillin is effective in treating its ocular manifestation as well.

“Owing to the location of their infection, patients are treated in the same way as cases of neurosyphilis,” the researchers explain. “Standard recommended treatment for neurosyphilis is 10 to 14 days of IC penicillin F, 4 million units every 4 hours.”

Reference

Schulz DC, Orr SMA, Johnstone R, Devlin MK, Sheidow TG, Bursztyn LLCD. The many faces of ocular syphilis: case-based update on recognition, diagnosis, and treatment. Can J Ophthalmol. Published online February 4, 2021. doi:10.1016/j.jcjo.2021.01.006.