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Home , Neisseria, Neisseria gonorrhoeae

gonorrhoeae by Real-time PCR with Reflex to resistance by Molecular Analysis

“The sensitivity and specificity of the nucleic acid amplification tests (NAATs) are clearly the highest of any of the test chorioamnionitis, premature birth, intrauterine growth retardation, platforms for the diagnosis of chlamydial and gonococcal neonatal , and postpartum . infections. Since accurate diagnosis is the goal, there is no • During vaginal delivery with an infected mother, 30% to 35% justification for the ongoing use of other technologies”(1, 2). of neonates will acquire which, if left - Centers for Disease Control and Prevention (CDC) untreated, can progress to corneal ulceration and scarring, as well as blindness called gonorrheal ophthalmia neonatorum. • MDL provides detection of Neisseria gonorrhoeae by Real- Time PCR, one of the most powerful and sensitive gene Laboratory Diagnosis analysis techniques available. • Diagnosis of infections with N. gonorrhoeae has traditionally • Sensitivity and specificity up to 99%. relied upon , culture, and immunochemical • Test results are typically available within 24-48 hours. techniques. Although culture techniques may be highly • This test has been validated for detection of N. gonorrhoeae specific, sensitivity is greatly impacted by the adequacy of the using the OneSwab®, UroSwab® (males and females), and ® clinical specimen and transport conditions, particularly when ThinPrep . transporting to off-site facilities. Epidemiology • Due to the genome plasticity of N. gonorrhoeae strains circulating in the population, this bacterium has developed • is the second most commonly reported bacterial resistance to multiple classes of antimicrobial agents, resulting STD in the United States with an estimated 700,000 new N. in decreased efficacy for gonorrhea therapy. An increase of gonorrhoeae infections occuring each year (7). -resistant N. gonorrhoeae demonstrated a similar • Due to the fact that gonococcal infections among women are pattern to previous reports in Japan and Southeast Asia that frequently asymptomatic, targeted screening of young women prompted the CDC to remove ciprofloxacin from the treatment at increased risk for infection is a primary component of guidelines as a primary antibiotic (1-3). gonorrhea control in the United States (7). • In August 2012, the CDC called for Ceph-R NG surveillance through N. gonorrhoeae antibiotic susceptibility testing for Pathogenesis patients that have failed treatment (3). Although susceptibility • Neisseria gonorrhoeae, a Gram-negative diplococci, is the testing by culture remains the standard for antibiotic causative agent of gonorrhea. susceptibility determination in clinical microbiology, there are • Due to its affinity for columnar or pseudo stratified , it inherent growth-related issues that can delay results by as is most commonly detected in the genital tract with the primary much as three days or more. • site of involvement being the endocervical canal and transition Known mechanisms of antibiotic resistance in N. gonorrhoeae zone of the . are linked to mutations in the chromosomal DNA as well as • N. gonorrhoeae’s unique ability to alter surface structures the presence of -borne genes. Surveillance of genetic allows increased pathogenicity, facilitates epithelial surface markers of antibiotic resistance is important for the prediction of attachment, and enables evasion of the host’s immune clinical resistance as the antibiotic susceptibility signatures of response. individual N. gonorrhoeae strains differ. • Transmission of N. gonorrhoeae occurs almost exclusively through sexual contact, though it can also be transmitted via the passage of a neonate through an infected mother’s birth canal or via autoinoculation from the hands of an infected person to their eye. • Incubation time for this infection is typically 3-5 days and transmission more frequently occurs from male to female. • Some risks factors for infection include: low socioeconomic status, early onset of sexual activity, unmarried status, a history of previous gonorrhea infection, illicit drug abuse, and prostitution. Clinical Significance

• Clinical manifestation in men usually includes symptomatic NOTE: PenR = penicillinase producing Neisseria gonorrhoeae and chromosomally mediated ; however, pharyngeal, anorectal, and disseminated -resistant N. gonorrhoeae; TetR = chromosomally and plasmid mediated - infections are also possible. resistant N. gonorrhoeae; and QRNG = quinolone-resistant N. gonorrhoeae. • In women, infections are often asymptomatic; however, when Figure 1: Gonococcal isolate surveillance project (GISP)-penicillin, manifested, symptoms may include: vaginal discharge, dysuria, tetracycline, and ciprofloxacin resistance among GISP isolates, 2010 (7). intermenstrual bleeding, menorrhagia, pelvic discomfort, infection of the periurethral glands, Bartholin glands, and • Test 167 Neisseria gonorrhoeae by Real-Time PCR (Reflex anorectum. to Antibiotic Resistance by Molecular Analysis) developed • Due to the fact that gonorrhea can have serious consequences by MDL, offers a valuable diagnostic tool for the reliable for both mother and neonate, it is crucial to screen pregnant detection of genetic determinants of antibiotic resistance, women for infection who reportedly have an incidence of thereby predicting antibiotic susceptibility of individual N. gonorrhea during pregnancy as high as 10%. gonorrhoeae strains in a given clinical specimen. This test • Complications that can occur during pregnancy include: amniotic addresses the problem of genetic variability in N. gonorrhoeae infection syndrome, premature rupture of the membranes, and delivers a prognostic recommendation for antibiotic therapy in a personalized manner. Medical Diagnostic Laboratories, L.L.C. • www.mdlab.com • 877.269.0090 Table 1: Comparison of Multiple Assay Systems for the Detection of Neisseria gonorrhoeae. Test N Ϯ Prevalence (%) Sensitivity (%) Specificity (%) PPV (%) NPV (%) References PCR 100 7.8 100 99.4 93.4 100 (17) Amplicor 2238 5.2  96.3 98.7 80.2  99.8  (18) Aptima Combo 2 1479 8.6 99.2 98.7 88.1 99.9 (19) BD Probe Tec 1411 8.1 97.2 99.4 91.6 99.6 (20) GEN-PROBE 1750 8.7 97.1 99.1 90.6 99.8 (21) (Pace 2) Culture 866 4.5 50.0 97.1 40.0 98.0 (22)

Ϯ = Unless otherwise noted, all specimens are swabs  = Calculated data Screening REFERENCES: Table 2: Summary of screening for N. gonorrhoeae infection by nucleic 1. Miller WC, Ford CA, Morris M, et al. 2004. Prevalence of acid amplification testing (NAAT) (derived from 7). Infections Among Young Adults in the United States. JAMA 291:2229- 2236. Women 2. Monif GR, Baker DA. Infectious Diseases in Obstetrics and • Annual routine screening for all sexually active women at risk Gynecology, Fifth Edition. New York, NY: The Parthenon Publishing for infection. Group; 2004:222-233. • Screening at the first prenatal visit for all pregnant women at risk 3. Mandell, GL, Bennett JE, Dolin R. Mandell, Douglas, and Bennett’s or living in a high prevalence area. Principles and Practices of Infectious Diseases, Vol 2. Philadelphia: Churchhill Livingstone; 2000:2242-2256. • In women with via either vaginal, cervical, or urine 4. Faro S, Soper DE. Infectious Diseases in Women. Philadelphia: W.B. samples. Saunders Company; 2001:435-450. Men who have sex with men (MSM) 5. Girdner JL, Cullen AP, Salama TG, et al. (1998). ASM Meeting. • Screening for urethral infection via nucleic acid amplification 6. Donders GF, VanGerven V, de Wet HG, et al. 1996. Scan J Infect Dis. testing (NAAT) of urine in all men who have had insertive 28:559-562. intercourse the preceding year regardless of use. 7. CDC. 2010. Sexually Transmitted Disease Guidelines. MMWR Vol. 59, • Screening for rectal infection via nucleic acid amplification testing no. RR-12. (NAAT) of a rectal swab in all men who have had receptive anal 8. Girdner JL, Cullen AP, Salama TG, et al. 1998. ASM Meeting. 9. Vlaspolder F, Mustaers JA, Blog F, et al. 1993. J Clin Microbiol intercourse during the preceding year. 31:107-110. • Screening for pharyngeal infection via nucleic acid amplification 10. Cullen A, He L, Arthur P, et al. 1998. ASM Meeting. testing (NAAT) in all men who have had receptive oral intercourse 11. Donders GF, VanGerven V, de Wet HG, et al. 1996. Scan J Infect Dis during the preceding year. 28:559-562. Both Men and Women 12. Johnson RE, Newhall WJ, Papp JR, et al. 2002. Screening tests to detect and Neisseria gonorrhoeae • Newly diagnosed HIV infection infections--2002. 13. CDC. 2002. MMWR Recomm Rep 2002 18;51(RR-15):1-38. 14. van Doornum GJ, Schouls LM, Pijl A, et al. 2001. Comparison Treatment between the LCx Probe System and the COBAS AMPLICOR System for Detection of Chlamydia trachomatis and Neisseria gonorrhoeae Table 3: Current Recommendations from the CDC for adults, adolescents Infections in Patients Attending a Clinic for Treatment of Sexually & children >45 kg: urogenital, rectal infection with N. gonorrhoeae (16). Transmitted Diseases in Amsterdam, The Netherlands. J Clin Microbiol 39(3):829-835. Recommended Regimens 15. Palmer HM, Mallinson H, Wood RL, Herring AJ. 2003. Evaluation of the Specificities of Five DNA Amplification Methods for the Detection of Ceftriaxone 250 mg IM in a single dose PLUS Neisseria gonorrheae. J Clin Microbiol 41(2):835-837. 1 g orally in a single dose 16. CDC. 2010. Update to CDC’s Sexually Transmitted Diseases Treatment Guidelines, Oral No Longer a Recommended OR Treatment for Gonococcal Infection. MMWR 61(31):590-594. Doxycycline 100 mg orally twice a day for 7 days 17. Gaydos CA, et al. 2003. Performance of the APTIMA Combo 2 assay for detection of Chlamydia trachomatis and Neisseria gonorrhoeae Alternative Regimens: If ceftriaxone is not an option in female urine and endocervical swab specimens. J Clin Microbiol 41(1):304-9. Cefixime 400 mg orally in a single dose PLUS 18. Van Der Pol B, et al. 2001. Multicenter evaluation of the BDProbeTec Azithromycin 1 g orally in a single dose ET System for detection of Chlamydia trachomatis and Neisseria gonorrhoeae in urine specimens, female endocervical swabs, and male OR urethral swabs. J Clin Microbiol 39(3):1008-16. Doxycycline 100 mg orally twice a day for 7 days 19. Crotchfelt KA, et al. 1997. Detection of Neisseria gonorrhoeae and Chlamydia trachomatis in genitourinary specimens from men and women by a coamplification PCR assay.J Clin Microbiol 35(6):1536-40. • Due to the concerns for developing patterns of antimicrobial 20. 510(k) Summary, http://www.fda.gov/cdrh/pdf/k974503. pdf. Device resistance, most current recommendations for treatment name: Roche Amplicor CT/NG Test For Neisseria gonorrhoeae. should be followed. Guidance can be obtained from the CDC Accessed 06/2007. website (http://w ww.cdc.gov/std/gisp) and state and local 21. Vlaspolder F, et al. 1993. Value of a DNA probe assay (Gen-Probe) health departments. compared wh that of culture for diagnosis of gonococcal infection. J Clin • If treatment is still unsuccessful, contact the CDC for a Microbiol 31(1):107-10. consultation. 22. Danders GG, et al. 1996. Rapid tests for Neisseria gonorrhoeae • Complete treatment guidelines for Chlamydia are available and Chlamydia trachomatis are not accurate for screening women with disturbed vaginal lactobacillary flora. Scand J Infect Dis :559-62. from the CDC http://www.cdc.gov/std/treatment/2010/vaginal- 28(6) discharge.htm. (Accessed March 28, 2012).

Medical Diagnostic Laboratories, L.L.C. • www.mdlab.com • 877.269.0090