The largest prospective series of ocular syphilis in the post-penicillin era, this study confirmed good visual outcomes after treatment irrespective of HIV status or time to presentation. It also found an unexpected and as yet unexplained preponderance for left-eye involvement in uniocular cases.
Increasing numbers of case reports and series in the literature suggest that ocular syphilis is on an upward trend. However, there have been no prospective, population-based studies evaluating the incidence and features of ocular syphilis.
To address this, the authors identified UK patients diagnosed with early intraocular syphilis between 2009 and 2011. An initial questionnaire was collected from treating ophthalmologists at baseline and again at six or more months after treatment.
Forty-one new cases (63 eyes) of intraocular syphilis were reported, for an annual incidence of 0.3 per million in the UK adult population. The mean age was 48.7 years; 90.2% were male. All had RPR/VDRL titers of ‡1:16.
Bilateral ocular involvement occurred in 56%; in unilateral cases, and the left eye was more commonly affected. The mean presenting visual acuity was 20/6. At final follow-up, 92.1% had visual acuity of 20/40 or better after antibiotic therapy.
They write that it is unclear why the incidence reported here does not reflect the exponential increase seen in infectious syphilis. This may be due to increased awareness due to various nationwide health campaigns and a resulting improvement in health-seeking behavior.
They also note that the predominance of left-eye involvement has not been previously reported in ocular syphilis. The reasons for the difference are unknown.
While this was an interesting and relevant study, it is important for readers to recognize that it included only patients with early intraocular syphilis.