Demonstration that origin of antimicrobial-resistant Neisseria gonorrhoeae is from an oral commensal bacterium

Contents of presentation
Recently, due to the diversification of sexual behaviors, cases of gonococcal infections have been reported not only in the urethra and cervix, but also in non-genital organs such as the pharynx and conjunctiva. Neisseria gonorrhoeae is a well-known causative agent of sexually transmitted diseases. Gonococcal conjunctivitis is a serious disease that can lead to corneal perforation and blindness if treatment is delayed. Gonococcal infections other than those affecting the genitals, especially those caused by oral sex, are often asymptomatic; hence, gonococcal infections of the pharynx may go unnoticed and become problematic later. In 2013, the U.S. Centers for Disease Control and Prevention raised the hazard level of the drug-resistant strains of Neisseria gonorrhoeae to the most serious “urgent threats” level. In the following year, the WHO issued a warning that Neisseria gonorrhoeae had become resistant to third-generation cephalosporins antibiotics (ceftriaxone; Rocephin®), making it the most notable antibiotic-resistant strain in the world. Neisseria gonorrhoeae is classified as a member of the genus Neisseria, which is endemic to the oral cavity. When Neisseria gonorrhoeae infects the pharynx, certain gene regions are altered (mutated) due to the gene transfer from those strains of Neisseria gonorrhoeae that are commensal bacteria in the oral cavity. This can be attributed to a special property of Neisseria gonorrhoeae to receive genes known as its natural transformation ability. This change (mutation) is thought to be a factor in the development of resistance to ceftriaxone, the last trump card in the antibiotic treatment of gonococcal infections.