An adult male presented to the Hawaii Health Department with a purulent urethral discharge. Urethral Gram stain examination led to a presumptive gonorrhea diagnosis even though his sexual history was nonsupportive. Culture results identified Neisseria meningitidis. This case report highlights the clinical similarities and differing epidemiology of these Neisseria urethritides.
The clinical presentation of Neisseria meningitidis urethritis is virtually identical to urethritis caused by Neisseria gonorrhoeae, however, the epidemiology is vastly different as highlighted by this case report.
From the *Department of Public Health Sciences, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI; and †Diamond Head Health Center, STD/AIDS Prevention Branch, Hawaii State Department of Health, Honolulu, HI
The authors thank Gail Kunimoto and Eloisa Maningas, Medical Microbiology Branch, HI Department of Health, State Laboratories Division for laboratory support.
Correspondence: Alan R. Katz, MD, Department of Public Health Sciences, John A. Burns School of Medicine, University of Hawaii, 1960 East-West Rd, Biomedical Sciences Bldg, Room D104M, Honolulu, HI 96822. E-mail: firstname.lastname@example.org.
Received for publication August 4, 2010, and accepted September 28, 2010.
Gonorrhea is the second most common nationally notifiable disease in the United States.1 Gonococcal infections in men are usually symptomatic and suspected when there is dysuria accompanied by purulent urethral discharge. Currently, most cases are confirmed using nucleic acid amplification tests (NAATs), but rapid laboratory diagnosis may be based on finding an increased number of polymorphonuclear leukocytes (PMNs) with Gram-negative intracellular diplococci (GNID) on a Gram-stained urethral swab specimen.2 However, neither NAAT nor Gram stain test are 100% specific, hence false-positive results are possible.3,4 The only diagnostic test result for gonorrhea with 100% specificity is to isolate Neisseria gonorrhoeae from a culture obtained from a clinical specimen. Sexual histories are necessary in interpreting laboratory results, however, the accuracy of self-reported sexual risk behaviors may be questionable.5 We present a case report of presumptive gonorrheal urethritis (based on clinical presentation and Gram stain findings) with an incompatible sexual history, which turned out to be a meningococcal urethritis most likely contracted from oral sex with a monogamous sexual partner.
On May 18, 2010, a 26-year-old man presented to the Diamond Head Health Center of Hawaii State Department of Health with a 5-day history of greenish penile discharge and dysuria. He reported being in a 7-month mutually monogamous relationship with a 22-year-old woman with whom he had been cohabitating for the past 5 months. He reported having oral and vaginal sex approximately once per week. He had no history of sexually transmitted diseases (STDs), was on no medications, had no smoking history, drank alcoholic beverages 3 times per week, and was employed as a security guard.
Physical examination revealed a small amount of purulent light green penile discharge. Gram stain of a urethral swabbed specimen revealed 60 to 80 PMNs per oil immersion field with GNID and Gram-negative extracellular diplococci. A Neisseria culture specimen was obtained from a urethral swab and plated on Martin–Lewis agar and a NAAT was performed for both N. gonorrhoeae and Chlamydia trachomatis from a second urethral swab using transcription mediated amplification (APTIMA Combo-2, Gen-Probe, San Diego, CA).
The patient was diagnosed as having presumptive gonococcal urethritis and was treated with 400 mg of cefixime and 1 gram of azithromycin orally and was advised to have his sexual partner examined and treated. The patient returned to the clinic within 1 week with his partner. The index case reported that his discharge had abated 2 days after treatment and his dysuria gradually decreased and finally abated 5 days post-treatment.
His female partner complained of a 7-day history of yellow vaginal discharge. Her sexual history corroborated that of the index case, both claiming a single monogamous partner over the past 7 months. She gave no prior history of STDs, was on no medications, and had a pap smear 3 months earlier which was reportedly within normal limits. She was employed in the beauty industry.
Pelvic examination revealed cervicitis with a moderate amount of yellow mucoid cervical and vaginal discharge. A Gram stain of an endocervical swabbed specimen demonstrated greater than 100 PMNs per oil immersion field without GNID or Gram-negative extracellular diplococci. A vaginal saline wet-mount specimen showed an increased number of PMNs, and a vaginal 10% potassium hydroxide wet-mount specimen was negative for yeast. An endocervical swabbed specimen was plated on Martin–Lewis media and a second endocervical swab was tested for C. trachomatis and N. gonorrhoeae, using transcription-mediated amplification (APTIMA Combo-2, Gen-Probe, San Diego, CA).
The female partner was treated with 125-mg intramuscularly ceftriaxone to cover the possibility of an oropharyngeal gonococcal infection. As the male partner's NAAT results had been reported as negative for C. trachomatis at the time of the female partner's visit, no azithromycin was administered.
The final laboratory results from the male patient revealed a positive urethral culture for Neisseria; however, API-NH biochemical testing results (bioMérieux, La Balme-les-Grottes, France) identified the isolate as N. meningitidis, not N. gonorrhoeae. The NAAT was negative for both N. gonorrhoeae and C. trachomatis. The endocervical swabbed culture specimen from the female partner showed no growth after 2 days, and the endocervical NAAT was also negative for N. gonorrhoeae and C. trachomatis.
Although relatively uncommon, N. meningitidis urethritis presents in a manner indistinguishable from N. gonorrhoeae.6–8 Although both conditions are related to sexual activity, their epidemiology is vastly different.
The rate of subclinical infection with N. meningitidis is high in the general population, with an estimated 5% to 10% prevalence of asymptomatic nasopharyngeal colonization.9 A recent serial cross-sectional study of college students in the United Kingdom revealed a 13.9% prevalence of nasopharyngeal carriage at the start of the fall semester which increased to 34.2% 2 months later.10 Chronic or at least long-term colonization has also been demonstrated in the general population.11 N. meningitidis has also been linked to symptomatic pharyngitis.12
Although the endocervical swabbed specimen was culture negative for N. meningitidis and no oral culture was obtained, the female sexual partner was the probable source of infection for our index case. She worked in the beauty industry and had close face-to-face prolonged contact with numerous clients which may have facilitated respiratory droplet exposure to N. meningitidis which she then transmitted to the index case through oral-genital contact. Although there are no studies, to our knowledge, demonstrating increased rates of N. meningitidis carriage among beauty industry workers, there is evidence supporting an association between nasopharyngeal carriage and occupations involving frequent social contacts.13 The etiology of her cervicitis remains unknown. The etiology of nongonococcal/nonchlamydial cervicitis is an important under-researched topic.14
Cases of urogenital meningococcal infections have been reported since the 1930s15 with a marked increase, beginning in the early 1970s including meningococcal urethritis,6,8,16–21 epididymitis,19 proctitis,16,17,20 cervicitis,6,21 and pelvic inflammatory disease.6,16,19 The increase has been attributed to changing sexual behaviors, specifically, an increased practice of oral sex, expanding the niche of N. meningitidis.8,18,21,22
Definitive diagnosis of gonococcal urethritis can only be made via culture isolation. Without an isolate, a NAAT may provide a presumptive diagnosis, but if used inappropriately (e.g., to screen persons from low prevalence population groups), the positive predictive value may be less than optimal and the test may yield false-positive results.4 A Gram-stained specimen from a symptomatic male's urethra demonstrating increased numbers of PMNs with GNIDs has been noted to have a sensitivity of 90% to 95% and a specificity of 95% to 100% for detection of gonorrhea3 but as this case report reminds us, the specificity is not 100%, and this point should be emphasized in textbooks and other reference materials. Gram stain findings of increased numbers of PMNs with GNIDs should be considered a presumptive gonorrhea diagnosis, nothing more; a definitive diagnosis requires laboratory confirmation.
The therapeutic approach to meningococcal and gonococcal urethritis is identical. Current Centers for Disease Control and Prevention treatment recommendations for uncomplicated gonococcal infection of the urethra are ceftriaxone 125-mg intramuscularly or cefixime 400 mg orally, both third generation cephalosporins (plus treatment for chlamydia if it has not been ruled out by NAAT).2 Third generation cephalosporins also provide excellent coverage for meningococcal infections.23 In the seminal textbook on STDs, Hook and Handsfield recommend that genital meningococcal infections “be managed in the same manner as gonorrhea.”3
The routine use of NAATs has in large part replaced cultures for gonorrhea diagnosis. The dual (chlamydia and gonorrhea) NAAT has dramatically improved chlamydia diagnostics and allowed for noninvasive urine-based screening for both infections. However, urethral N. gonorrhoeae cultures from symptomatic males have high sensitivity (≥90%)3 and should be recommended when assessing symptomatic males with positive urethral Gram stain findings but sexual histories that are incompatible with a gonorrhea diagnosis.
Although neither of our patients reported emotional distress with the misdiagnosis, both were visibly relieved when informed of their final laboratory results. A number of studies have documented the adverse psychosocial impact of being diagnosed with a sexually transmitted infection including, anxiety, guilt, shame, feelings of decreased self worth, and bitterness toward ones sexual partner.24–26
In conclusion, we leave the reader with a warning from a 1998 ProMED-mail post: “... correct identification of the organism in acute male urethritis might occasionally save a marriage, when the organism is N. meningitidis from the wife's throat rather than N. gonorrhoeae from extracurricular sources.”27
1.Centers for Disease Control and Prevention. Summary of notifiable diseases—United States, 2008. Morb Mortal Wkly Rep 2008; 57:1–94.
2.Centers for Disease Control and Prevention. Sexually transmitted diseases treatment guidelines, 2006. MMWR Recomm Rep 2006; 55:42.
3.Hook EW III, Handsfield HH. Gonococcal infections in the adult. In: Holmes KK, Sparling PF, Stamm WE, et al, eds. Sexually Transmitted Diseases, 4th ed. New York, NY: McGraw-Hill, 2008:627–645.
4.Katz AR, Effler PV, Ohye RG, et al. False-positive gonorrhea test results with a nucleic acid amplification test: The impact of low prevalence on positive predictive value. Clin Infect Dis 2004; 38:814–819.
5.Schroder KE, Carey MP, Vanable PA. Methodological challenges in research on sexual risk behavior. II: Accuracy of self reports. Ann Behav Med 2003; 26:104–123.
6.Hagman M, Forslin L, Moi H, et al. Neisseria meningitidis
in specimens from urogenital sites: Is increased awareness necessary? Sex Transm Dis 1991; 18:228–232.
7.McKenna JG, Fallon RJ, Moyes A, et al. Anogenital non-gonococcal Neisseriae
: Prevalence and clinical significance. Int J STD AIDS 1993; 4:8–12.
8.Urra E, Alkorta M, Sota M, et al. Orogenital transmission of Neisseria meningitidis
serogroup C confirmed by genotyping techniques. Eur J Clin Microbiol Infect Dis 2005; 24:51–53.
9.Heymann DL, ed. Control of Communicable Disease Manual, 19th ed. Washington, DC: American Public Health Association, 2008:415–421.
10.Neal KR, Nguyen-Van-Tam JS, Jeffrey N, et al. Changing carriage rate of Neisseria meningitidis
among university students during the first week of term: Cross sectional study. BMJ 2000; 320:846–849.
11.Yazdankhah SP, Caugant DA. Neisseria meningitidis
: An overview of the carriage state. J Med Microbiol 2004; 53:821–832.
12.Mattila PS, Carlson P. Pharyngolaryngitis caused by Neisseria meningitidis.
Scand J Infect Dis 1998; 30:198–200.
13.Caugant DA, Høiby EA, Magnus P, et al. Asymptomatic carriage of Neisseria meningitidis
in a randomly sampled population. J Clin Microbiol 1994; 32:323–330.
14.Marrazzo JM, Martin DH. Management of women with cervicitis. Clin Infect Dis 2007; 44:S102–S110.
15.Murray EG. Meningococcal infections of the male urogenital tract and the liability to confuse with gonococcus infection. Urol Cutaneous Rev 1939; 43:739–741.
16.Givan KF, Thomas BW, Johnston AG. Isolation of Neisseria meningitidis
from the urethra, cervix, and anal canal: Further observations. Br J Vener Dis 1977; 53:109–112.
17.Judson FN, Ehret JM, Eickhoff TC. Anogenital infection with Neisseria meningitidis
in homosexual men. J Infect Dis 1978; 137:458–463.
18.Miller MA, Millikin P, Griffin PS, et al. Neisseria meningitidis
urethritis: A case report. JAMA 1979; 242:1656–1657.
19.William DC, Felman YM, Corsaro MC. Neisseria meningitidis
: Probable pathogen in two related cases of urethritis, epididymitis, and acute pelvic inflammatory disease. JAMA 1979; 242:1653–1654.
20.Faur YC, Wilson ME, May PS. Isolation of N. meningitidis
from patients in a gonorrhea screening program: A four-year survey in New York City. Am J Public Health 1981; 71:53–58.
21.Conde-Glez CJ, Calderón E. Urogenital infection due to meningococcus in men and women. Sex Transm Dis 1991; 18:72–75.
22.Edwards S, Carne C. Oral sex and the transmission of non-viral STIs. Sex Transm Infect 1998; 74:95–100.
23.Apicella MA. Neisseria meningitidis.
In: Mandell GL, Bennett JE, Dolin R, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, 7th ed. Philadelphia, PA: Churchill Livingstone Elsevier, 2010:2737–2752.
24.Newton DC, McCabe MP. A theoretical discussion of the impact of stigma on psychological adjustment to having a sexually transmissible infection. Sex Health 2005; 2:63–69.
25.Holgate HS, Longman C. Some peoples' psychological experiences of attending a sexual health clinic and having a sexually transmitted infection. J R Soc Health 1998; 118:94–96.
26.Ross MW. Psychological perspectives on sexuality and sexually transmitted diseases and HIV infection. In: Holmes KK, Sparling PF, Stamm WE, et al, eds. Sexually Transmitted Diseases, 4th ed. New York, NY: McGraw-Hill, 2008:137–148.
27.ProMED-mail. Meningitis, meningococcal: Venereal transmission. ProMED-mail 1998; 5 March:19980305.0418. Available at: http://www.promed.org
. Accessed August 3, 2010.