Special Precautions/Comments:

Interferences: Endocervical, Anorectal and Oropharyngeal swab samples >10% (v/v) blood may give invalid or false negative results.

Patients who have used over-the-counter feminine hygiene and prescription products tested in urogenital specimens; Metronidazole, Replens, RepHresh Odor Eliminating Vaginal Gel and RepHresh Clean Balance produced false negative or invalid results.

Products containing carbomer(s), including vaginal lubricants and creams may interfere with the test and should not be used prior/during specimen collection.

Eye swabs may give invalid results if the eye has been washed prior to sampling.

Method:  Real-time polymerase chain reaction (PCR). Calibration: cobas® 6800/8800 system. EQA scheme: QCMD and NEQAS. IQC: cobas® commercial preparations.

Interpretation: Results are reported as NOT detected, Inconclusive, or DETECTED by PCR. A negative result does NOT fully exclude infection. POSITIVE results must be discussed with Sexual Health for advice. Positive results may require confirmatory testing, this will be completed using a different PCR assay.

Additional Information:

Background information:  Chlamydia trachomatis is the leading bacterial cause of sexually transmitted infections worldwide.  CT causes a variety of infections including urethritis, cervicitis, proctitis, conjunctivitis, endometritis, and salpingitis; if left untreated, the infection may ascend to the uterus, fallopian tubes, and ovaries causing pelvic inflammatory syndrome, ectopic pregnancy, and tubal factor infertility. Reiter’s syndrome (urethritis, conjunctivitis, arthritis, and mucocutaneous lesions) has also been associated with genital CT infection. Many infections remain asymptomatic. Patients often become re-infected if their sexual partners are not treated. Infants born to infected mothers can develop conjunctivitis, pharyngitis, and pneumonia. The predominant symptoms in men and women are increased discharge and dysuria; women may also present with irregular uterine bleeding.

Neisseria gonorrhoeae is the causative agent of gonorrhoea and is the second most commonly reported communicable disease.  Clinical manifestations are numerous, in men urethritis, discharge, dysuria, epididymitis or rarely no symptoms. There is a high prevalence of coalescence of symptoms with CT, Trichomonas vaginalis, and vaginosis; many women remain asymptomatic. In symptomatic women increased discharge, dysuria, and intermenstrual bleeding may be observed. Pelvic inflammatory disease (PID) can occur in 10%-20% of women, combined with endometritis, salpingitis, tubo-ovarian abscess, pelvic peritonitis, and perihepatitis. PID can result in tubal scarring that can lead to infertility and ectopic pregnancy. Other gonococcal infected sites in men and women are the rectum, pharynx, conjunctiva, and to a lesser degree the disease presents itself as disseminated gonococcal infection. Infants from infected mothers can develop conjunctivitis.