Evaluation of the Bio-Rad BioPlex 2200 Syphilis Multiplex Flow Immunoassay for the Detection of IgM- and IgG-Class Antitreponemal Antibodies

Abstract

The laboratory diagnosis of syphilis is based primarily upon serologic findings. Historically, serologic testing for syphilis has relied on assays such as rapid plasma reagin, fluorescent treponemal antibody absorption,

Evaluation of the BioPlex 2200 Syphilis System as a First-Line Method of Reverse-Sequence Screening for Syphilis Diagnosis

“…Many studies are available comparing performances of different methods for syphilis diagnosis in routine use, taking into account sensitivity and specificity, as well as cost, ease of use, and suitability of automation (9-12, 33, 34). Regarding new MFI technology, Gomez et al tested the BioPlex 2200 Syphilis system (26), suggesting that it may prove beneficial to clinical laboratories experiencing increasing test volumes for syphilis serologic testing. Nevertheless, in that study, as stressed by the authors themselves, the lack of clinical information to arbitrate discordant results between different assays was a major limit for the further interpretation of the results.…”

“…The principle of MFI technology for syphilis diagnosis has been previously explained (26). Briefly, samples are added to reaction vessels containing bead reagent and sample diluent.…”

“…Percent agreement, kappa coefficient, and sensitivity and specificity with 95% confidence intervals (CI) were calculated. Result agreement by kappa values is categorized as nearly perfect (0.81 to 1.0), substantial (0.61 to 0.8), moderate (0.41 to 0.6), fair (0.21 to 0.4), slight (0 to 0.2), or poor (Ͻ0) (26).…”

Direct Comparison of the Traditional and Reverse Syphilis Screening Algorithms in a Population with a Low Prevalence of Syphilis

“…Samples that are reactive by EIA are then tested by RPR to assess disease and treatment status and provide a supplemental marker of infection (1,2,6). The implementation of reverse screening has allowed clinical laboratories to meet increasing demands for syphilis testing by providing an automated screening test that yields an objective interpretation of results (4). However, the results of reverse screening often cause confusion and anxiety among health care providers and patients, especially when the results of EIA screening and RPR are discordant (e.g., reactive by EIA and non-reactive by RPR).…”

Laboratorial Diagnosis of Syphilis

“…For anti-treponemal IgM antibody detection, BioPlex IgM MFI assay showed 80% (4/5) sensitivity and 97.9% (652/666) specificity, when compared to the Trep-Chek IgM EIA (Phoenix-Biotech). BioPlex syphilis MFI assay allow for a fully automated random-accesses platform that provides fast (1.7h for 100 samples) and high throughput (800 samples per 9 hours) analysis of the syphilis serologic response (Gomez et al, 2010).…”