TABLE 2.
Effect of storage and retesting of urine specimens to which C. trachomatis was introduced before processing by the APTIMA Combo 2 and LCx assaysa
| Dilution | No. of negative urine specimens/no. of false-negative specimens after addition of C. trachomatis EBs (%) |
||
|---|---|---|---|
| APTIMA Combo 2 assay |
LCx assayb with 12 EBs | ||
| 12 EBs | 1 EB | ||
| Neat | 0/2 (0) | 2/7 (28.6) | 19/40 (47.5) |
| 1:4 | 0/2 (0) | 2/7 (28.6) | 18/40 (45.0) |
| False-negative result reduction | 0/415 (0) | 2/244 (0.8) | 18/334 (5.4) |
a
The specimens were kept at 4°C overnight.
b
There was sufficient volume to retest only 40 of 44 false-negative urine specimens by the LCx assay.