Table 2.
Sensitivity of PCR for the detection of Chlamydia trachomatis in synovial fluid depending on DNA extraction method and primer system used
| Amplification system | 1 Alkaline Lysis | 2 Qiaex II gel extraction kit® | 3 Chelex® | 4 Qiagen Tissue kit® | 5 Qiagen Stool kit® |
|---|---|---|---|---|---|
| (C. trachomatis EB/ml SF) | (C. trachomatis EB/ml SF) | (C. trachomatis EB/ml SF) | (C. trachomatis EB/ml SF) | (C. trachomatis EB/ml SF) | |
| PCR 1 | 1 | 0.1 | 100 | 1 | 1 |
| C. trachomatis | (0.1-10) | (1-100) | (10-100) | (1-10) | (1-100) |
| omp 1 | M1 | M 1 | M 100 | M 1 | M 100 |
| Statistical analysis | * 2,5 | * 1,4 | * 2 | * 1 | |
| PCR 2 | 10 | 1000 | 1000 | 10 | 10 |
| C. trachomatis | (10) | (1-1000) | (100-1000) | (0.1-10) | (10-1000) |
| omp 1 | M 10 | M 1000 | M 1000 | M10 | M 10 |
| Statistical analysis | * 2 | * 1,4,5 | * 2 | * 2 | |
| PCR 3 | 1 | 100 | 1000 | 1 | 100 |
| Plasmid | (0.1-10) | (10-1000) | (1000) | (1-10) | (10-1000) |
| M 1 | M 100 | M 1000 | M 1 | M 100 | |
| Statistical analysis | * 2,3,5 | * 1,3,4,5 | * 1,2 | * 2,3 | * 1,2,4 |
| PCR 4 | 1 | 10 | 1000 | 10 | 100 |
| 16 sRNA | (0.1-10) | (10-1000) | (10-1000) | (0.1-10) | (10-100) |
| M 1 | M 100 | M 1000 | M 10 | M 10 | |
| Statistical analysis | * 2,3,5 | * 1,4,5 | * 1 | * 2,3 | * 1,2 |
| LCR | 10 | 1 | 10000 | 10 | 100 |
| Plasmid | (0.1-100) | (1-100) | (100-1000) | (10- 100) | (1-1000) |
| M 10 | M 100 | M 1000 | M 10 | M 100 | |
| Statistical analysis | * 2 | * 1,3,4,5 | * 2 | * 2 | * 2 |
Synovial fluid was spiked with isolated C. trachomatis- elementary bodies (C. trachomatis EB) per ml synovial fluid (SF) ranging from 10,000 C. trachomatis EB/ml SF to 0.1 C. trachomatis-EB/ml SF in 10-fold decreasing concentrations. Five independent repeats of each serial dilution was performed (n = 5) for each DNA extraction method and amplification system evaluated. The range of detection limits of each method is given in brackets, median (M) of serial dilutions given below. Sensitivity was defined as reproducibly detected lowest number of detected C. trachomatis EB/ml SF. Statistical analysis: significant results are indicated in order of method compared. Statistical significant results are indicated by *, method compared with is indicated by number (P < 0.05). LCR = ligase chain reaction; omp-1 = major outer membrane protein.