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The BD ProbeTec™ GC Q^x Amplified DNA Assay, when tested with the BD Viper™ System in Extracted Mode, uses Strand Displacement Amplification technology for the direct, qualitative detection of Neisseria gonorrhoeae DNA in clinician-collected female endocervical and male urethral swab specimens, patient-collected vaginal swab specimens (in a clinical setting), and male and female urine specimens. The assay is also intended for use with gynecological specimens collected in BD SurePath™ Preservative Fluid or PreservCyt™ Solution using an aliquot that is removed prior to processing for either the BD SurePath or ThinPrep™ Pap test. The assay is indicated for use with asymptomatic and symptomatic individuals to aid in the diagnosis of gonococcal urogenital disease.

The World Health Organization estimates that 62 million new cases of infection due to Neisseria gonorrhoeae are diagnosed each year.¹ In the United States, gonorrhea is the second most commonly reported infectious disease with over 358,000 cases in 2006.² During this period, for the first time in 10 years the reported rate of infection was higher among women than men.² Infection of women is often asymptomatic and if left untreated can lead to pelvic inflammatory disease, infertility, ectopic pregnancy and chronic pelvic pain. In men, symptoms of acute urethritis and dysuria usually cause infected individuals to present for treatment before serious sequelae result. Transmission of N. gonorrhoeae occurs through sexual contact but can also take place in the birth canal leading to neonatal conjunctivitis.

Because of the high frequency of asymptomatic infections, the US Preventive Services Task Force has published recommendations for screening young, sexually active women and those who are older and considered at increased risk of infection in order to prevent complications and reduce transmission.³ The Advisory Committee on Human Immunodeficiency Virus (HIV) and Sexually Transmitted Disease (STD) Prevention also encourages active control programs that target treatable STDs as a primary intervention in the HIV epidemic.⁴ Nevertheless, a recent rise in fluoroquinolone resistance has reduced the options available to combat N. gonorrhoeae infection such that administration of cephalosporins is the only treatment recommended by the Centers for Disease Control and Prevention.⁵

N. gonorrhoeae are gram-negative, oxidase-positive diplococci that can be observed in Gram-stained smears of urethral discharge, usually within neutrophils. Culture of N. gonorrhoeae can be difficult because the organism does not survive long outside the host and is highly susceptible to adverse environmental conditions such as lack of humidity and temperature extremes. Although culture of urogenital swabs remains an important tool in the diagnosis of N. gonorrhoeae infection due to the continued need for monitoring of antimicrobial susceptibility, use of molecular methods that amplify and detect specific nucleic acid sequences is increasing due to their applicability to both swab specimens and more easily collected urine specimens.^6,7

When used with the BD Viper System, the BD ProbeTec GC Q^x Amplified DNA Assay involves automated ferric oxide-based extraction of DNA from clinical specimens using BD Fox™ Extraction technology with the chemical lysis of cells, followed by binding of DNA to para-magnetic particles, washing of the bound nucleic acid and elution in an amplification-compatible buffer. When present, N. gonorrhoeae DNA is then detected by Strand Displacement Amplification (SDA) of a specific target sequence in the presence of a fluorescently-labeled detector probe.^8,9

Quality control must be performed in accordance with applicable local, state and/or federal regulations or accreditation requirements and your laboratory's standard Quality Control procedures. It is recommended that the user refer to pertinent CLSI guidance and CLIA regulations for appropriate Quality Control practices.

The Control Set for the BD ProbeTec CT/GC Q^x Amplified DNA Assays is provided separately. One Positive and one Negative Control must be included in each assay run and for each new reagent kit lot number. Controls must be positioned according to the BD Viper Instrument User's Manual. The CT/GC Q^x Positive Control will monitor for substantial reagent failure only. The CT/GC Q^x Negative Control monitors for reagent and/or environmental contamination. Additional controls may be tested according to guidelines or requirements of local, state, and/or federal regulations or accrediting organizations. Refer to CLSI C24-A3 for additional guidance on appropriate internal quality control testing practices.¹⁴ The Positive Control contains approximately 2400 copies per mL of pCTB4 and pGCint3 linearized plasmids.

The Extraction Control (EC) oligonucleotide is used to confirm the validity of the extraction process. The EC is dried in the Extraction Tubes and is re-hydrated by the BD Viper System upon addition of the specimen and extraction reagents. At the end of the extraction process, the EC fluorescence is monitored by the instrument and an automated algorithm is applied to both the EC and N. gonorrhoeae-specific signals to report specimen results as positive, negative, or EC failure.

Each BD ProbeTec GC Q^x Reagent Pack contains:

- GC Q^x Amplified DNA Assay Priming Microwells, 12 x 96: each Priming Microwell contains approximately 30 pmol oligonucleotides, 45 pmol fluorescently-labeled detector probe, 100 nmol dNTPs, with stabilizers and buffer components.

- GC Q^x Amplified DNA Assay Amplification Microwells, 12 x 96: each Amplification Microwell contains approximately 140 units DNA polymerase and 500 units restriction enzyme, with stabilizers and buffer components.

NOTE: Each microwell pouch contains one desiccant bag.

Control Set for the BD ProbeTec CT/GC Q^x Amplified DNA Assays: 24 CT/GC Q^x Positive Control Tubes containing approximately 2400 copies each of pCTB4 and pGCint3 linearized plasmids in carrier nucleic acid, and 24 CT/GC Q^x Negative Controls Tubes containing carrier nucleic acid alone. The concentrations of the pCTB4 and pGCint3 plasmids are determined by UV spectrophotometry.

Q^x Swab Diluent for the BD ProbeTec Q^x Amplified DNA Assays: 48 tubes each containing approximately 2 mL of potassium phosphate/potassium hydroxide buffer with DMSO and preservative.

Liquid-Based Cytology Specimen (LBC) Dilution Tube for the BD ProbeTec Q^x Amplified DNA Assays (LBC Specimen Dilution Tube): 400 tubes each containing approximately 1.7 mL of Tris/Sodium Chloride solution and preservative.

BD Fox Extraction Tubes: 48 strips of 8 tubes, each containing approximately 10 mg of iron oxide in a dissolvable film and approximately 240 pmol fluorescently-labeled Extraction Control oligonucleotide.

BD Viper Extraction Reagent and Lysis Trough: each 4-cavity Extraction Reagent trough contains approximately 16.5 mL Binding Acid, 117 mL Wash Buffer, 35 mL Elution Buffer, and 29 mL Neutralization Buffer with preservative; each Lysis Trough contains approximately 11.5 mL Lysis Reagent.

General:

1. For in vitro Diagnostic Use.

2. Pathogenic microorganisms, including hepatitis viruses and Human Immunodeficiency Virus, may be present in clinical specimens. "Standard Precautions" ^10-13 and institutional guidelines should be followed in handling all items contaminated with blood and other body fluids.

3. For additional specific warnings, cautions and notes specific to the BD Viper, consult the BD Viper System User's Manual.