C-163. Detection of Chlamydia trachomatis and Neisseria gonorrhoeae in Urine using the BD ProbeTec™ CTQx and GCQx Amplified DNA Assays on the BD Viper™ System in Extracted Mode
We have developed two novel assays for the detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) on the BD Viper™ System in extracted mode. Here we describe the analytical performance of the new BD ProbeTec™ CTQx and GCQx Amplifed DNA Assays with Neat urine (without preservative) as well as urine specimens stored in the Urine Preservative Transport (UPT) for the BD ProbeTec™ (CT/GC) Qx amplified DNA assays. Both the Neat and UPT urine samples utilized with pierceable caps and were extracted on the BD Viper System. The analytical sensitivities of the CTQx and GCQx assays with Neat and UPT-treated urine were determined by spiking pooled CT/GC negative specimens from healthy donors at the following target levels: 0, 1, 3, 7, 15, and 30 Elementary Bodies (EBs)/mL for CT and 0, 5, 10, 20, 50, and 100 particles/mL for GC. The 95% limits of detection (LODs) for CT and GC with Neat urine were *14 EBs/mL (95% confidence intervals: 8, 21 EBs/mL) and *21 particles/mL (12, 30), respectively, while for UPT-treated urine the LODs were *6 EBs/mL (4, 9) and *25 particles/mL (13, 38). Specimen stability studies were conducted using multiple pools of Neat and UPT-treated urine that were spiked with CT and GC organisms at a low level near the analytical LODs of the Qx assays, and which were then stored under different conditions. CT and GC DNA were successfully detected in Neat urine stored at 30°C for up to 30 hours and at 2-8°C for up to 7 days. With UPT-treated urine, CT and GC DNA were stable at 2-30°C for up to 30 days. Stability of CT/GC DNA was also demonstrated when Neat urine specimens were held at 2-8°C for up to 24 hours and 30°C for up to 8 hours prior to transfer to the UPT. The BD ProbeTec CTQx and GCQx assays, when used in conjunction with extraction on the BD Viper System, were able to detect low numbers of organisms in both Neat and UPT-treated urine. The stability of the CT/GC DNA in Neat and UPT-treated urine specimens with pierceable caps was also demonstrated over a broad range of temperatures that provide flexible alternatives for transport and storage prior to extraction on the BD Viper System. Product not for sale, for investigational use only in the US.