Article

Qualitative and quantitative aspects of the serological diagnosis of early syphilis

Scottish Bacterial Sexually Transmitted Infections Reference Laboratory, Laboratory Medicine (Microbiology), 51 Little France Crescent, Edinburgh, Scotland, UK.
International Journal of STD & AIDS (Impact Factor: 1.05). 10/2008; 19(9):620-4. DOI: 10.1258/ijsa.2008.008103
Source: PubMed

ABSTRACT

The aim of the present study was to evaluate the use of various serological tests in the diagnosis of early syphilis. The Murex enzyme immunoassay (EIA) test was used for screening; the Venereal Diseases Research Laboratory (VDRL) test, the Treponema pallidum particle agglutination assay (TPPA) and the Mercia antitreponemal IgM EIA were used in all the patients with a positive screening test and in those with suspected syphilis or in known contacts. In 89 cases of primary syphilis, the Murex EIA screening test was positive in 67 (75%) patients, the Mercia IgM EIA in 80 (90%) cases, the VDRL in 60 (67%) cases and the TPPA in 85 (96%) cases. All the tests were positive in 68 patients with secondary syphilis. In 72 cases of early latent syphilis, the Murex EIA screening test was positive in 68 (94%) patients, the Mercia IgM EIA in 50 (69%) cases, the VDRL in 61 (85%) cases and the TPPA in 68 (94%) cases. The Mercia IgM EIA was the only test positive in four (6%) of these cases; these four patients were known contacts. Antibody titres in the VDRL and TPPA increased as the infection progressed.

Full-text preview

Available from: ceescat.org
  • Source
    • "Serological tests for syphilis lack sensitivity and though some may be helpful in assessing the stage of infection, they are unreliable [7]. In determining the stage, particularly in asymptomatic patients, clinicians thus rely on previously documented syphilis tests, anamnesis (i.e. "
    [Show abstract] [Hide abstract]
    ABSTRACT: In recent years, the number of syphilis cases has stabilised in many countries of Western Europe, however several countries have reported increases among men who have sex with men (MSM). The aim of this article was to describe the epidemiology of early syphilis in Norway in 1992-2008. Cases of early syphilis and congenital syphilis reported to the Norwegian Surveillance System for Communicable Diseases (MSIS) 1992-2008 were described by route of transmission, gender, age, birthplace, stage of disease, HIV co-infection, source partner and place of infection. The incidence of reported syphilis ranged from 0.05 (1992) to 1.50 (2002) per 100 000 person-years. Of 562 cases reported to MSIS during the study period, 62% were men infected by another man. The proportion of those, infected homosexually increased from 0 (1992-1994) to 77% (2008). Most of them were Norwegians (83%). The proportion of HIV co-infection among homosexually infected increased over time and reached 39% in 2008. The majority reported being infected by a casual partner (73%) and in the municipality of Oslo (72%). Of 152 heterosexually infected men 64% were Norwegians; 51% were infected by casual contacts and 20% by commercial sex workers; 73% were infected abroad. Among 56 women, 57% were Norwegians, 57% were infected by a steady partner and 40% were infected abroad. Almost half (46%) were diagnosed in the early latent stage. Four cases had congenital syphilis, two of whom were adopted from abroad. Syphilis is rare in Norway, but MSM represent almost two thirds of cases. The increase of HIV co-infected cases among MSM may enhance transmission of both infections. We recommend sexually active MSM to be tested for syphilis 2-4 times a year. Due to its variable clinical course, syphilis might be difficult to recognise at an early stage among women in a low-prevalence population. We estimate current practice of prenatal screening in Norway as sufficient.
    Full-text · Article · Apr 2010 · BMC Infectious Diseases
  • [Show abstract] [Hide abstract]
    ABSTRACT: To determine the sensitivity and specificity of the Architect Syphilis Chemiluminescence Assay (CLIA): a new highly automated screening test for syphilis. To establish the sensitivity of the Architect Syphilis assay we tested 129 stored sera from serologically characterised cases of untreated syphilis. The sera were selected to contain a disproportionately high number of primary infections. There were 79 primary infections, 29 secondary infections, 9 early latent infections and 12 latent syphilis of unknown duration. To establish the specificity of the assay we tested 1107 sera that had been submitted for routine syphilis serology. The Architect CLIA and the Treponema pallidum particle agglutination test (TPPA) were in total agreement for all untreated infection with sensitivity of 98.4%. This was significantly higher than the sensitivity of the Murex immune capture enzyme (ICE) immunoassay (86%, p<0.001), the IgM enzyme immunoassay (EIA) (86.8%, p<0.001) and the Venereal Disease Research Laboratory test (VDRL) (83.7%, p<0.001). The difference in the sensitivity of the Architect and ICE assays was entirely due to primary stage syphilis (97.5% vs 77.2%, p<0.001). Although the specificity of Architect CLIA was very high (99.1%, 1049/1059) it was significantly lower (p = 0.016) than that of the Murex ICE assay (99.9%). The Architect CLIA is significantly more sensitive than the Murex ICE screening assay in detecting primary syphilis but it is significantly less specific. Given the relatively high levels of early syphilis, we consider a small increase in the number of confirmatory tests required to exclude false-positive results is worthwhile to increase the detection of primary syphilis by 20%.
    No preview · Article · Oct 2008 · Sexually transmitted infections
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The aim of the study was to compare reactivity in the Mercia immunoglobulin M enzyme immunoassay (IgM EIA) and the Venereal Disease Research Laboratory (VDRL) after treatment of 229 previously untreated patients with early syphilis. At three months, the VDRL and the IgM EIA were negative in 41 (38%) and 71 (62%) cases, respectively; a four-fold or greater decrease in VDRL titre occurred in 106 (99%). At six months, the VDRL and the IgM EIA were negative in 45 (48%) and 69 (71%) patients, respectively; a four-fold or greater decrease in VDRL titre occurred in 88 (95%) and an eight-fold or greater decrease in 80 (86%). At 12 months, the VDRL and the IgM EIA were negative in 35 (70%) and 55 (92%) patients, respectively; a four-fold or greater decrease in VDRL titre occurred in 49 (98%) and an eight-fold or greater decrease in 47 (94%). The Mercia IgM EIA is as sensitive as the VDRL in monitoring treatment of primary syphilis but not as sensitive as the finding of a four-fold or eight-fold decrease in VDRL titre in patients treated for secondary or early latent infection.
    Preview · Article · Nov 2008 · International Journal of STD & AIDS
Show more