A 25-year-old man comes to the physician because of a 4-day history of pain and burning with urination and frequent urinary urgency. He is sexually active and has several female partners; he does not use condoms. His temperature is 37°C (98.6°F). Urinalysis shows 2+ protein; cultures grow on chocolate agar. A Gram stain shows gram-negative diplococci. The organism causing this patient’s symptoms most likely produces which of the following virulence factors?
A. Elementary bodies
C. Free radicals
Pili-although it does not produce any exotoxins, neisseria gonorrhoeae has a wide range of virulence determinants. the first stages of infection, which includes adherence and invasion, are mediated by surface components. the bacterium first attaches to epithelial cells by means of its fimbriae, specifically n-methylphenylalanine (type iv) pili, with the main subunit pile. after initial attachment, the bacteria enter a second stage of binding mediated by the outer membrane protein p.ii (also known as opa) which is needed for tight binding and invasion of epithelial cells. also, p.ii from one bacterium will bind to los of an adjacent bacterium, which allows for the construction of a small colony that may function similarly to a biofilm. neisseria gonorrhoeae also produces an iga1 protease that may take part in the colonization stage.the outer membrane porin of n. gonorrhoeae p.i (also known as por) is equivalent to the ompc and ompf porins of e. coli. they are involved in the passage of solutes through the outer membrane. however, p.i apparently has a role in virulence that allows the gonococci to survive inside of phagocytes. purified p.i has also been shown to inhibit the ability of phagocytes to kill ingested bacteria. the lipooligosaccharide (los) is thought to be responsible for most of the symptoms of gonorrhea. gonococcal los triggers an intense inflammatory response. the activation of complement, attraction and feeding by phagocytes, and the lysing of the phagocytes themselves, contributes to the purulent discharge. the local production of tnf is thought to be the main cause of damage to the fallopian tubes. in addition, in strains that cause systemic infection, los binds sialic acid from the serum forming a microcapsule of sialylated los, which allows the gonococci to resist the host immune response and serum bactericidal reaction