Table 4.
Diagnostic Accuracy of Three POC Kits for Toxoplasma IgG and IgM Detection
| POC Kit | Toxoplasma Antibodies | Sensitivity (%) (95% CI) |
Specificity (%) (95% CI) | NPVb (%) (95% CI) |
PPVb (%) (95% CI) |
|---|---|---|---|---|---|
| Biopanda | IgG | 100 (97.8–100) |
96.3 (89.5–98.9) | 100 (95.3–100) | 98.3 (95.0–99.5) |
| IgM | 62.2 (51.4–71.9) |
88.5 (82.7–92.5) |
82.5 (76.2–87.4) | 72.9 (61.5–81.9) |
|
| OnSite | IgG | 100 (97.8–100) | 97.5 (91.3–99.6) |
100 (95.3–100) | 98.8 (95.8–99.8) |
| IgM | 28.0 (19.5–38.6) |
97.6 (93.9–99.1) |
73.2 (66.9–78.6) |
85.2 (67.5–94.1) |
|
| LDBIOa | IgG/IgM Combined | 100 (97.8–100) |
98.8 (93.2–99.9) |
100 (95.4–100) | 99.4 (96.8–99.9) |
Abbreviations: CI, confidence interval; Ig, immunoglobulin; POC, point of care; NPV, negative predictive value; PPV, positive predictive value.
aAs the LDBIO-POC test reports Toxoplasma IgG and IgM antibodies combined in a single testing band (T band), specificity for LDBIO-POC test was calculated over 80 seronegative sera (Toxoplasma-IgG−/IgM−)
bThe above PPV and NPV for the 3 POC tests are representative of the performance of these tests in a group of samples in which 33% were Toxoplasma IgM+ and 68% were Toxoplasma IgG+. In pragmatic clinical settings, the prevalence of Toxoplasma IgM+ individuals is significantly lower (usually <1% [<10 of 1000]).