Delay in the diagnosis of early syphilis among men who have sex with men: need for greater community and health provider education

INTRODUCTION

In recent years, a resurgence of syphilis has been seen among men who have sex with men (MSM) in a number of industrialized countries including Australia, posing new challenges to the control of this infection. ¹ Syphilis is infectious during its early phase, when the typical symptoms and signs of primary infection may be clinically mild or atypical, leading to unrecognized or undiagnosed infection. ² Optimal control of syphilis requires the early detection and treatment of infectious cases to prevent further transmission of infection. ²

To our knowledge, there have been no studies that have specifically aimed to determine the duration between the onset of symptoms of early syphilis in MSM and its diagnosis. This study aimed to identify any significant delay in the diagnosis of syphilis among MSM.

METHODS

We undertook a review of all cases of early symptomatic syphilis (primary and secondary) in MSM diagnosed at the Melbourne Sexual Health Centre (MSHC), Victoria, between January 2003 and August 2007. During the study period, patients could attend MSHC with or without a referral from a general practitioner (GP). All cases were serologically confirmed by enzyme immunoassay and/or Treponema pallidum particle agglutination test. Polymerase chain reaction (PCR) for T. pallidum was used selectively where lesions of early syphilis were suspected.

As the time period between onset of symptoms and treatment was of interest, cases of early latent syphilis were excluded. Also cases of early syphilis were excluded that had already been diagnosed and treated elsewhere prior to their attendance at MSHC.

Data on recent reported sexual behaviour of men in the study were analysed. Information was also collated on: reported HIV status, date of onset of self-reported symptoms of syphilis infection (genital lesions or rash), date of syphilis diagnosis (when positive serology and/or PCR was received), and date of commencement of syphilis treatment. To assess whether syphilis was considered as the diagnosis by referring GPs, the referral letters from practitioners who had referred men to MSHC were reviewed. Time periods were compared with the Mann-Whitney test using SPSS version 15 (SPSS Inc., Chicago, IL, USA).

RESULTS

The study included 123 men. This included 34 men who had presented to a GP first and who were subsequently referred to MSHC and 89 men who presented to MSHC themselves.

The mean age of men was 37 years. Fifty-two percent (n = 64) presented with primary syphilis and 48% (n = 59) with secondary syphilis. Twenty-five percent (n = 30) were known to be HIV-positive. Twenty-nine percent (n = 45) had lesions that were tested positive by T. pallidum PCR. The median rapid plasma reagin titre among men was 1:32.

Of the 34 cases that were referred to MSHC by GPs, on review of referral letters from those GPs, there was no evidence that referring practitioners had considered the diagnosis of syphilis for 10 men with primary syphilis and 20 men with secondary syphilis.

For all cases of early syphilis, the median time between onset of symptoms and confirmation of diagnosis, and onset of symptoms and treatment, was 15 (range: 3–56) and 20 (range: 1–57) days, respectively. The respective times for secondary syphilis (17 and 23 days) were longer than for primary syphilis (13 and 15 days) (P < 0.05). Time to treatment was not significantly lower for those who were diagnosed positive by PCR. The mean number of male sex partners reported by men for the prior three months was 8.8 (range: 1–15). During this time, 99% reported anal sex with other men, 51% of whom reported any unprotected anal sex.

DISCUSSION

If early diagnosis and treatment of infectious syphilis is to be optimized as a core component of syphilis control, it will require early symptom recognition by infected individuals, prompt presentation to health-care providers, and the correct diagnosis to be made by the health-care provider. This study has shown that in our setting, there was a delay of about two weeks between the onset of symptoms of early syphilis and its diagnosis, a period during which further transmission could have occurred. Furthermore, it appears that the diagnosis of syphilis was missed by most referring GPs. That the latter occurred more frequently with secondary syphilis, and as time to diagnosis was greater for secondary syphilis, this suggests that the early diagnosis of secondary syphilis is particularly challenging.

There are a number of limitations to this study. First, it is likely that the time to diagnosis and treatment varies considerably between different populations where symptom recognition and access to quality health care are different. Therefore, the time periods found in this study may not apply to different settings. It is likely that even longer delays would exist in more remote or more resource-limited settings. Secondly, we do not know where the main delays occurred: whether these were mainly related to delayed symptom recognition or delayed health-seeking. It is likely these would have differed between men. Thirdly, we could only determine if a GP had entertained a diagnosis of syphilis by examining their referral letter. It is possible that GPs had considered the diagnosis but not explicitly stated this in their referring letter. We may therefore have overestimated the proportion who missed the diagnosis.

That there are delays in the diagnosis of syphilis is perhaps not surprising. While there may have been a resurgence of syphilis among MSM in a number of countries, syphilis is still encountered infrequently by most primary care providers. ³ The challenge of making the correct diagnosis is compounded by the diverse and often atypical way in which syphilis can present. Secondary syphilis for instance can have protean manifestations and may mimic other common dermatological conditions. ²

Efforts at reducing delays in syphilis diagnosis should include education of health-care providers about the symptoms and signs of syphilis and the need to consider syphilis testing of MSM presenting with suggestive symptoms and signs. ³ There should also be campaigns in raising awareness of syphilis among affected groups, with particular reference to its symptoms and signs and the need for early treatment. For example, at MSHC, we have posted images of early syphilis on our website to assist clinicians and people in the community with recognition of early syphilis (http://www.mshc.org.au/syphilis/). While we have focused on symptomatic syphilis, the importance of screening for early latent syphilis, which can account for a substantial proportion of cases of early syphilis among MSM, should not be overlooked, together with measures that enhance such screening. ⁴