Ocular syphilis in Pacific peoples-are we making misdiagnoses secondary to yaws?

To determine the demographic and clinical features of patients with ocular disease consistent with syphilis and positive treponemal serology in Auckland, and to compare patients who lived in a Pacific nation before 1960 with all other patients with regard to these features, considering a possible history of yaws infection.

Retrospective review of subjects seen in uveitis and neuroophthalmology clinics at Auckland District Health Board between January 2006 and June 2019.

Two thousand four hundred and ninety-three subjects were reviewed in uveitis clinics during the timeframe, of whom 45 were diagnosed with syphilitic uveitis (1.8%). Mean age was 56.2±14.8 years and 34 (75.5%) were male. Ethnicity was Caucasian in 16 (35.5%), Pacific peoples in 16 (35.5%), Māori in two (4.4%), Asian in six (13.3%) and other in five (11.1%). Pacific peoples were older at presentation (p=0.001) and 75.0% were aged >60 compared to 24.1% of non-Pacific peoples (p=0.002). Comparing Pacific people born prior to 1960 (aged >60) to the rest of the cohort, older Pacific subjects had lower RPR titres (median 3 vs 32 p=0.004), less optic nerve swelling (0% vs 28.0% eyes p=0.014) and less posterior uveitis (6.25% vs 32.0% eyes p = 0.033). No difference was observed in anterior and intermediate uveitis between the groups. No difference was observed in the resolution or recurrence of inflammation between the groups.

Syphilitic uveitis is common in New Zealand, occurring in 1 in 55 patients seen in consultant uveitis clinics. Clinicians should consider a history of yaws in Pacific peoples presenting with ocular inflammation and positive treponemal serology. In these cases alternative causes of ocular pathology should be included as differentials. In cases of diagnostic uncertainty, the risk of treatment versus the potentially severe sequelae of untreated syphilis need to be considered.