Background: Annual syphilis testing was reintroduced in the Swiss HIV Cohort Study (SHCS) in 2004. We prospectively studied occurrence, risk factors, clinical manifestations, diagnostic approaches and treatment of syphilis.
Methods: Over a period of 33 months, participants with positive test results for Treponema pallidum hemagglutination assay were studied using the SHCS database and an additional structured case report form.
Results: Of 7244 cohort participants, 909 (12.5%) had positive syphilis serology. Among these, 633 had previously been treated and had no current signs or symptoms of syphilis at time of testing. Of 218 patients with newly detected untreated syphilis, 20% reported genitooral contacts as only risk behavior and 60% were asymptomatic. Newly detected syphilis was more frequent among men who have sex with men (MSM) [adjusted odds ratio (OR) 2.8, P < 0.001], in persons reporting casual sexual partners (adjusted OR 2.8, P < 0.001) and in MSM of younger age (P = 0.05). Only 35% of recommended cerebrospinal fluid (CFS) examinations were performed. Neurosyphilis was diagnosed in four neurologically asymptomatic patients; all of them had a Venereal Disease Research Laboratory (VDRL) titer of 1:≥32. Ninety-one percent of the patients responded to treatment with at least a four-fold decline in VDRL titer.
Conclusion: Syphilis remains an important coinfection in the SHCS justifying reintroduction of routine screening. Genitooral contact is a significant way of transmission and young MSM are at high risk for syphilis. Current guidelines to rule out neurosyphilis by CSF analysis are inconsistently followed in clinical practice. Serologic treatment response is above 90% in the era of combination antiretroviral therapy.
aClinic for Infectious Diseases, Bern University Hospital and University of Bern, Bern, Switzerland
bDivision of Infectious Diseases, University Hospital and University of Zurich, Zurich, Switzerland
cDivision of Dermatology and Division of Infectious Diseases, University Hospital of Geneva, Geneva, Switzerland
dDivision of Infectious Diseases, University Hospital of Lausanne, Lausanne, Switzerland
eDivision of Infectious Diseases, University Hospital of Basel, Basel, Switzerland
fDivision of Infectious Diseases, Cantonal Hospital of St-Gallen, St-Gallen, Switzerland
gDivision of Infectious Diseases, Cantonal Hospital of Lugano, Lugano, Switzerland
hInstitute of Social and Preventive Medicine, University of Bern, Bern, Switzerland.
Received 8 February, 2010
Revised 7 May, 2010
Accepted 10 May, 2010
Correspondence to Hansjakob Furrer, MD, Universitätsklinik für Infektiologie, University Hospital Bern, Inselspital PKT2 B, CH-3010 Bern, Switzerland. Tel: +41 31 632 27 45; fax: +41 31 632 31 76; e-mail: email@example.com