Neisseria gonorrhoeae

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Neisseria gonorrhoeae
Neisseria gonorrhoeae cultured on two different media types.
Scientific classification
Kingdom: Bacteria Phylum: Proteobacteria Class: Beta Proteobacteria Order: Neisseriales Family: Neisseriaceae Genus: Neisseria Species: N. gonorrhoeae
Binomial name
Neisseria gonorrhoeae Zopf, 1885

Neisseria gonorrhoeae, also known as Gonococci (plural), or Gonoccus (singular), is a species of Gram-negative bacteria responsible for the sexually transmitted disease gonorrhoea.^[1]

Neisseria are fastidious cocci, requiring nutrient supplementation to grow in laboratory cultures. Specifically, they grow on Chocolate agar (heated blood agar) with carbon dioxide. These cocci are facultatively intracellular and typically appear in pairs (diplococci).

Gonorrhoea symptoms include a purulent (or pus-like) discharge from the genitals which may be foul smelling, a burning sensation during urination and conjunctivitis. Conjunctivitis is common in neonates and Silver nitrate is often applied to their eyes as a preventive measure against gonorrhoea. Neisseria is usually isolated on Thayer-Martin agar — an agar plate with three different antibiotics and nutrients which not only facilitate the growth of Neisseria species, but inhibit the growth of Gram-positive organisms and most bacilli and fungi. Further testing to differentiate the species includes testing for oxidase (all Neisseria show a positive reaction) and the carbohydrates maltose, sucrose, and glucose test in which N. gonorrhoeae will only oxidize (that is, utilize) the glucose.

If N. gonorrhoeae is resistant to the penicillin family of antibiotics, then ceftriaxone (a third-generation cephalosporin) is often used.

Patients should also be tested for Chlamydia infections, since co-infection is frequent.

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