Table 1 Comparison of positive B. pertussis patient specimens by real-time RT-PCR assays Average crossing threshold (Ct) values and standard deviations (SD) for each combination of PCR and conventional results are shown. Samples were selected based on results for DFA/culture IS481 HP PCR.
From: Evaluation of real-time PCR for diagnosis of Bordetella pertussis infection
Result combination | IS481HP Assay | IS481MB Assay* | TPR Assay* | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Â | Positive/tested (%) | Average Ct of positives | SD of positives | Positive/tested (%) | Average Ct of positives | SD of positives | Positive/tested (%) | Average Ct of positives | SD of positives |
DFA negative Culture negative Screen PCR (IS481HP) positive | 28/28 (100.0) | 35.7 | 3.9 | 26/28 (92.9) | 40.4 | 3.2 | 15/28 (53.6) | 40.1 | 2.1 |
DFA negative Culture positive Screen PCR (IS481HP) positive | 17/17 (100.0) | 31.6 | 5.4 | 17/17 (100.0) | 36.5 | 5.7 | 15/17 (88.2) | 37.7 | 5.0 |
DFA positive Culture positive Screen PCR (IS481HP) positive | 21/21 (100.0) | 24.9 | 3.8 | 21/21 (100.0) | 30.1 | 3.9 | 21/21 (100.0) | 32.3 | 3.4 |