TABLE 1.
Comparison of the ViraChip MIB assays and ViraStripe LIA for detection of anti-B. burgdorferi IgM and IgG antibodies in serum
| ViraChip assay and resulta | ViraStripe assay and no. to tests with indicated resultb |
% agreement (95% CI)c |
Kappa value (95% CI) | ||||
|---|---|---|---|---|---|---|---|
| Positive | Negative | Uninterpretable | Positive | Negative | Overall | ||
| IgM MIB | IgM LIA (n = 411) | ||||||
| Positive | 160 | 1 | 1 | ||||
| Negative | 49d | 191 | 4 | 75.5 (69.2–80.8) | 99.0 (96.1–99.9) | 85.6 (81.9–88.7) | 0.71 (0.65–0.78) |
| Invalid | 3 | 1 | 1 | ||||
| IgG MIB | IgG LIA (n = 411) | ||||||
| Positive | 122 | 25 | 0 | ||||
| Negative | 9 | 253 | 0 | 93.1 (87.3–96.5) | 90.4 (86.3–93.3) | 91.2 (88.1–93.6) | 0.81 (0.75–0.87) |
| Invalid | 0 | 2 | 0 | ||||
a
MIB, microarray immunoblot; LIA, line immunoassay.
b
The ViraChip IgM MIB assay detected antibodies to only p41 in 37/49 samples and to only p23 in only 1 sample. The ViraChip IgM MIB assay did not detect antibodies to p39 in any of the 49 discordant samples.
c
CI, confidence interval.
d
Eleven samples had 0 bands, and 38 samples had only 1 band detected by the ViraChip IgM MIB assay.