by Alison Bowler

Created on: June 05, 2009   Last Updated: July 13, 2009

Gonorrhea, sometimes known as the clap, is a sexually transmitted disease caused by the bacterium Neisseria gonorrhoeae. Neisseria species are gram-negative staining diplococci. In a gram smear, the diplococci are seen as pairs of red staining slightly kidney shaped cocci.

Neisseria gonorrhoeae is killed by prolonged exposure to atmospheric oxygen levels and by drying out, so gonorrhea cannot be caught from the toilet seat! A person catches gonorrhoeae by intimate, sexual contact with an infected person. Neisseria gonorrhoeae can infect the vagina, urethra, rectum and throat so all forms of unprotected sexual activity carry the danger of infection.

A patient with gonorrhea will sometimes have a thick yellow colored discharge from the infected site. Other patients, particularly females, may be asymptomatic. Because women are frequently asymptomatic, they often fail to seek any form of treatment. This can lead to serious complications.

Without treatment, gonorrhea in females may cause pelvic inflammatory disease (PID). PID increases the risk of an ectopic pregnancy and may lead to infertility. A rare systemic complication of gonorrhea is septic arthritis where the bacterium infects the fluid surrounding a joint. Gonococcal septic arthritis occurs more frequently when treatment in delayed. It is more common in females than in males.

A newborn infant may catch gonorrhea at birth from its mother. Such babies will often develop severe eye infections and N. gonorrhoeae can be isolated from swabs taken from their eyes. If left untreated this eye infection leads to blindness.

Within specialized Sexually Transmitted Diseases clinics, a gram stain of a smear from an infected site will give a provisional diagnosis of gonorrhea. Using a microscope, the laboratory technician looks for intracellular gram-negative diplococci. It is important that the bacteria be seen within the phagocytic polymorphonuclear cells to distinguish infecting Neisseria species from other harmless gram-negative cocci that may be colonizing the site. This rapid method is not suitable for diagnosing oral gonorrhea as N. meningitidis can often be found in the throat and cannot be distinguished microscopically from N. gonorrhoeae.

A culture is required for confirmation of the disease. Neisseria are fastidious organisms requiring an agar medium enriched with lysed or heated (chocolatized) blood for growth. They also require incubation in a carbon dioxide enriched atmosphere. It will

• 1
• 2
• Next Page >>