Borrelia multiplex: a bead-based multiplex assay for the simultaneous detection of Borrelia specific IgG/IgM class antibodies

Table 2 Sensitivity and specificity of Borrelia multiplex against a commercial 2-step diagnostics

Classification	Sensitivity		Specificity
Classification	Manual processing	Automated processing	Manual processing	Automated processing
IgG + IgM	2-Step testing positive: 42 Borrelia multiplex: positive consensus: 40 Sens.: 95.2% (84.2–99.2%) PPV: 47.6%	2-Step testing positive: 42 Borrelia multiplex: positive consensus: 36 Sens.: 85.7% (72.2–93.3%) PPV: 53.7%	2-Step testing negative: 620 Borrelia multiplex: negative consensus: 576 Spec.: 93.0% (90.6–94.7%) NPV: 99.7%	2-Step testing negative: 620 Borrelia multiplex: negative consensus: 589 Spec.: 95.0% (93.0–96.5%) NPV: 99.0%
IgG	2-Step testing positive: 39 Borrelia multiplex: positive consensus: 37 Sens.: 94.9% (83.1–99.1%) PPV: 80.4%	2-Step testing positive: 39 Borrelia multiplex: positive consensus: 32 Sens.: 82.1% (67.3–91.0%) PPV: 80.0%	2-Step testing negative: 623 Borrelia multiplex: negative consensus: 614 Spec.: 98.6% (97.3–99.2%) NPV: 99.7%	2-Step testing negative: 623 Borrelia multiplex: negative consensus: 615 Spec.: 98.7% (97.5–99.3%) NPV: 98.9%
IgM	2-Step testing positive: 7 Borrelia multiplex: positive consensus: 5 Sens.: 71.4% (35.9–94.9%) PPV: 11.6%	2-Step testing positive: 7 Borrelia multiplex: positive consensus: 5 Sens.: 71.4% (35.9–94.9%) PPV: 17.2%	2-Step testing negative: 655 Borrelia multiplex: negative consensus: 617 Spec.: 94.2% (92.1–95.7%) NPV: 99.7%	2-Step testing negative: 655 Borrelia multiplex: negative consensus: 631 Spec.: 96.3% (94.6–97.5%) NPV: 99.7%

Sensitivity and specificity were determined based on a comparison with a 2-step diagnostics consisting of an ELISA and an immunoblot (both Virotech Diagnostics). The determination was carried out for IgG and IgM detection separately as well as for a combined analysis of both antibody classes. In total 662 samples of the MuSPAD study were analyzed. Number of positive and negative samples with both the commercial 2-step testing and the Borrelia multiplex are indicated. Percentage indicates Borrelia multiplex performance (sensitivity/specificity) compared to the commercial 2-step testing. 95% CI calculated by Wilson/Brown are shown. PPV—positive predictive value. NPV—negative predictive value.

ISSN: 1471-2334