Treponemal Assay Research Articles

Field evaluation of the performance and testing costs of a rapid point-of-care test for syphilis in a red-light district of Manaus, Brazil

Objectives:To assess the performance, usefulness and cost of a rapid treponemal antibody assay (VisiTect Syphilis) to detect syphilis in high risk populations.Methods:People who attended STI clinics in Manaus, Brazil, were...

Cost-Effectiveness of On-Site Antenatal Screening to Prevent Congenital Syphilis in Rural Eastern Cape Province, Republic of South Africa

On-site screening and same-day treatment of maternal syphilis in underresourced settings can avert greater numbers of congenital syphilis cases, but health outcomes and associated costs must be evaluated jointly. We used decision analysis to estimate the incremental cost-effectiveness of two on-site antenatal syphilis screening strategies to avert congenital infections-qualitative RPR (on-site RPR) and treponemal immunochromatographic strip assay (on-site ICS)-compared to the current practice (off-site RPR/TPHA). With antenatal active syphilis prevalence of 6.3%, the incremental cost-effectiveness of on-site ICS in averting congenital infections was estimated to be USD104, averting 82% of cases expected in absence of a program. The incremental cost-effectiveness of off-site RPR/TPHA was USD82 but would avert only 55% of congenital syphilis cases. On-site RPR was dominated by the other screening strategies. In settings of high maternal syphilis prevalence, on-site antenatal screening with ICS is a cost-effective approach to reduce the incidence of congenital syphilis.

Update on ocular syphilis

The present review updates the reader on publications from the past 5 years relevant to ocular syphilis. Articles from this period are easily grouped into three categories: descriptions of syphilitic ocular manifestations, ocular syphilis in the setting of HIV infection, and treatment of syphilitic ocular disease. While all of the entities described were previously recognized, many are unusual and their description in connection with syphilis is a reminder to be vigilant for this uncommon but everpresent disease. Ocular syphilis can be more severe in patients with HIV infection who are not taking highly active antiretroviral therapy, while with this treatment syphilis is an increasingly likely cause of ocular inflammation. Ocular syphilis should be treated like neurosyphilis, with daily intravenous or intramuscular penicillin for 2 weeks. The prevalence of syphilis has increased markedly in the past 5 years, most notably among men who have sex with men. The fluorescent treponemal antibody assay and similar tests remain the appropriate diagnostic tests for syphilis in patients with ocular inflammation. Syphilis lingers on the differential diagnosis of all forms of ocular inflammation and should be considered when evaluating such patients.

Syphilitic nodules on the tongue

Syphilitic nodules on the tongue

False positive reactions in confirmatory tests for syphilis in presence of antiphospholipid antibodies: misdiagnosis with prognostic and social consequences

False-positive reactions in the Venereal Disease Research Laboratory test are well known, whereas a positive fluorescent treponemal antibody absorption assay is rarely thought to be a false positive. The non-recognition of serological false-positive tests for syphilis may have negative prognostic and social implications.

IgG Western Blot as a Confirmatory Test in Early Syphilis

Sensitivity and specificity of IgG detection by Western blotting performed with a lysate of Treponema pallidum whole cells were compared with those of the most common assays used in the laboratory diagnosis of syphilis, i.e. fluorescent treponemal antibody absorption test (FTA-ABS) and treponemal haemagglutination assay (TPHA). Thirty-five serum samples obtained from twenty-one patients with a clinical diagnosis of early syphilis, based on the presence of typical chancre or skin or mucous membrane lesions, were studied. In addition, thirty blood samples from donors, ten sera positive for Borrelia burgdorferi and five positive for Leptospira interrogans were tested as controls. The clinical diagnosis was the reference method used to compare the performance of the serological tests. Western blotting performed with a sensitivity and specificity of 100%, whereas the corresponding sensitivity and specificity for FTA-ABS were 88.5% and 98%, respectively. The performance of TPHA showed a sensitivity of 86% and a specificity of 100%.

Syphilis Exposure in Patients with Uveitis

The purpose of the study is to determine the frequency of syphilis exposure in patients with uveitis, identify patient characteristics associated with serologic fluorescent treponemal antibody assays (FTA-ABS) reactivity, and examine the clinical implications of syphilis exposure in patients with uveitis. A retrospective review of the records of 552 consecutive patients examined in the referral uveitis clinic of an urban eye hospital between January 1989 and January 1994 was performed. Forty-four (8%) of 552 consecutive patients with uveitis had serologic evidence of syphilis exposure on the basis of a strongly reactive serum FTA-ABS. Syphilis was presumed to be the sole cause of uveitis in 24 patients (4.3%) over the 5-year period. The racial demographic profile of those patients with serologic evidence of syphilis was consistent with the reported distribution of syphilis cases, but there were relatively few identifiable risk factors for sexually transmitted disease (including only three patients who were positive with human immunodeficiency virus). The choice of antibiotic treatment of these patients was variable and sometimes suboptimal. This study implicates syphilis exposure as a more common etiology of uveitis than did previous reports, advocates routine serum FTA-ABS testing of patients with uveitis, and indicates a need for a more aggressive role of the ophthalmologist in antibiotic treatment of patients with uveitis and syphilis exposure.

Lumbar Puncture for Evaluation of Latent Syphilis in Hospitalized Patients

To determine the prevalence of abnormal neurologic findings and cerebrospinal fluid abnormalities in hospitalized patients with serologic evidence of latent syphilis. Cross-sectional survey. Consecutively admitted hospital inpatients from an inner-city population were screened for serologic evidence of syphilis with reactive plasma reagin and confirmatory fluorescent treponemal antibody absorption assays. In those with reactive tests, such clinical findings as a history of treatment for syphilis, neurologic abnormalities, presence of human immunodeficiency virus infection, and rapid plasma reagin titer were correlated with cerebrospinal fluid white blood cell count, protein level, and VDRL result. Of 490 consecutive patients, 52 (11%) had serologic evidence of syphilis. Forty-three (83%) of these underwent lumbar puncture. Of the 43, 31 (72%) were seronegative for human immunodeficiency virus and 12 (28%) were seropositive. No patient had a reactive cerebrospinal fluid VDRL test. Cerebrospinal fluid abnormalities were seen in 32% of human immunodeficiency virus-seronegative patients and in 67% of human immunodeficiency virus-seropositive patients. Cerebrospinal fluid abnormalities were not predicted by history of treatment for syphilis, abnormal neurologic findings, or an elevated rapid plasma reagin titer. Cerebrospinal fluid IgG indexes in patients with elevated cerebrospinal fluid protein levels suggested that the protein abnormalities were not caused by local antibody production. Nonreactive cerebrospinal fluid fluorescent treponemal antibody absorption tests suggest that the cerebrospinal fluid abnormalities were not the result of neurosyphilis. There was a high prevalence of cerebrospinal fluid abnormalities in hospitalized patients with latent syphilis detected by routine screening. Because of the nonspecificity of the cerebrospinal fluid findings, routine lumbar puncture for such patients appears to contribute little to the treatment of latent syphilis.

Effects of HIV infection on the serologic manifestations and response to treatment of syphilis in intravenous drug users.

To describe the effects of human immunodeficiency virus (HIV) infection on the serologic manifestations and response to treatment of syphilis in intravenous drug users. Cohort study of intravenous drug users. Medical clinic in a hospital-based methadone maintenance treatment program in New York City. Fifty patients with syphilis, of whom 31 were HIV seropositive and 19 HIV seronegative. Serologic tests for syphilis and clinical manifestations. Stage of syphilis at presentation was not associated with HIV serologic status. No unusual or fulminant manifestations of early syphilis or neurosyphilis were noted among HIV-seropositive cases. Maximum nontreponemal titers were higher among HIV-seropositive (median, 1:128) than among HIV-seronegative (median, 1:32) patients with syphilis (P = 0.05); this difference was present only among patients with first-episode syphilis. All 26 evaluable, HIV-seropositive patients treated for syphilis responded appropriately, including 13 patients given standard or less-than-standard doses of penicillin. Seven of 43 patients (16%) showed reversion to negative treponemal antibody assay results after treatment for syphilis; this finding was not associated with HIV infection, CD4 count, or stage of syphilis. Low nontreponemal titer was weakly associated with treponemal test reversion. Infection with HIV did not alter the stage at presentation, clinical course, serologic manifestations, or response to treatment of syphilis in this cohort of intravenous drug users.