Neisseria gonorrhoeae nucleic acid hybridization test
What is this test?
This test detects gene sequences in bacterial DNA. It is used to help diagnose infections caused by a bacteria called Neisseria gonorrhoeae (gonorrhea). A sample of endocervical cells or urethral cells or discharge may be collected for this test.
What are other names for this test?
- Neisseria gonorrheae nucleic acid hybridization test
Why do I need this test?
Laboratory tests may be done for many reasons. Tests are performed for routine health screenings or if a disease or toxicity is suspected. Lab tests may be used to determine if a medical condition is improving or worsening. Lab tests may also be used to measure the success or failure of a medication or treatment plan. Lab tests may be ordered for professional or legal reasons. The following is a possible reason why this test may be done:
- Gonorrhea of genitourinary tract, acute
When and how often should I have this test?
When and how often laboratory tests are done may depend on many factors. The timing of laboratory tests may rely on the results or completion of other tests, procedures, or treatments. Lab tests may be performed immediately in an emergency, or tests may be delayed as a condition is treated or monitored. A test may be suggested or become necessary when certain signs or symptoms appear.
Due to changes in the way your body naturally functions through the course of a day, lab tests may need to be performed at a certain time of day. If you have prepared for a test by changing your food or fluid intake, lab tests may be timed in accordance with those changes. Timing of tests may be based on increased and decreased levels of medications, drugs or other substances in the body.
The age or gender of the person being tested may affect when and how often a lab test is required. Chronic or progressive conditions may need ongoing monitoring through the use of lab tests. Conditions that worsen and improve may also need frequent monitoring. Certain tests may be repeated to obtain a series of results, or tests may need to be repeated to confirm or disprove results. Timing and frequency of lab tests may vary if they are performed for professional or legal reasons.
How should I get ready for the test?
Written consent will be required for endocervical sampling. Review the consent form with the healthcare worker and ask any questions that you have before signing the consent form.
Tell the healthcare worker if you have a medical condition or are using a medication or supplement that causes excessive bleeding. If possible, schedule the procedure one week after your menstrual period. Do not douche or have sexual intercourse for 24 hours before the procedure.
You may be asked to urinate prior to your endocervical sampling. This will make it easier for the healthcare worker to see your cervical canal during the procedure and may make the procedure more comfortable for you.
Before collection of urethral cells and/or urethral discharge for this test, you should not urinate during the hour prior to the test. This is because urine may minimize or clear your urethra (the tube that drains urine) of any organisms (germs), thus affecting the results of this test.
Urinate an hour or more before a sample is collected.
How is the test done?
A sample of endocervical cells or urethral cells or discharge may be collected for this test.
For an endocervical sampling, you will be asked to lie on your back with your legs spread and feet placed in stirrups. A speculum will be inserted into your vagina. This tool is used to gently spread apart your vagina. A small brush is inserted into the endocervical canal and rotated. This is done to collect cells. Once a sufficient sample is collected, the brush is removed. The sample off the brush is then sent for testing.
A urethral culture procedure is used to collect cells samples and/or urethral discharge. This test is usually done on males only. For this procedure, you will be asked to lie on your back. The tip of the penis will be cleaned. A special thin swab will be inserted into the urethra. The swab will gently be twisted side to side and then remain still for a few seconds before it is removed. This is to allow the swab to absorb enough fluid to be cultured. It may be possible to get a sample by “milking” the urethra for discharge. Ask the healthcare worker if this is an appropriate option.
How will the test feel?
The amount of discomfort you feel will depend on many factors, including your sensitivity to pain. Communicate how you are feeling with the person doing the procedure. Inform the person doing the procedure if you feel that you cannot continue with the procedure.
You may feel mild discomfort, cramping, or pain during an endocervical sampling.
A urethral culture generally takes less than a minute. However, you may feel discomfort when the swab moves in the urethra.
What should I do after the test?
After endocervical sampling, you may experience some light spotting (mild, occasional bleeding from the vagina). Generally, there are no activity restrictions after this procedure.
After a sample has been collected, avoid all sexual activities until you receive your results and speak to your healthcare worker.
What are the risks?
Endocervical cells: An endocervical cell sample is collected using a method similar to a Pap smear. This procedure may cause light bleeding from the vagina. If you have a medical condition, or are using a medication or supplement that causes excessive bleeding, you are at a higher risk of bleeding during or after this procedure. The person doing this procedure may need to perform it more than once. Talk to your healthcare worker if you have any concerns about the risks of this procedure.
Urethral cells/discharge: Ask the healthcare worker to explain the risks of this procedure to you before it is performed.
What are normal results for this test?
Laboratory test results may vary depending on your age, gender, health history, the method used for the test, and many other factors. If your results are different from the results suggested below, this may not mean that you have a disease. Contact your healthcare worker if you have any questions. The following is considered to be a normal result for this test:
What follow up should I do after this test?
Ask your healthcare worker how you will be informed of the test results. You may be asked to call for results, schedule an appointment to discuss results, or notified of results by mail. Follow up care varies depending on many factors related to your test. Sometimes there is no follow up after you have been notified of test results. At other times follow up may be suggested or necessary. Some examples of follow up care include changes to medication or treatment plans, referral to a specialist, more or less frequent monitoring, and additional tests or procedures. Talk with your healthcare worker about any concerns or questions you have regarding follow up care or instructions.
If you have a positive urethral culture, you may need to have the test repeated to monitor the treatment of your diagnosed condition. Additionally, all of your sexual partners may need to be treated. Follow the instructions given to you by your healthcare worker regarding sexual activities.
Where can I get more information?
- Johnson RE, Newhall WJ, Papp JR, et al: Screening tests to detect Chlamydia trachomatis and Neisseria gonorrhoeae infections--2002. MMWR Recomm Rep 2002; 51(RR-15):1-38.
- Koumans EH, Johnson RE, Knapp JS, et al: Laboratory testing for Neisseria gonorrhoeae by recently introduced nonculture tests: a performance review with clinical and public health considerations.. Clin Infect Dis 1998; 27:1171-1180.
- Glass N, Nelson H, Villemyer K: Screening for gonorrhea: Update of the evidence. Agency for Healthcare Research and Quality (AHRQ). Rockville, MD. 2005. Available from URL: www.preventiveservices.ahrq.gov. As accessed June 10, 2005.