STD: Bacterial

Rates of gonorrhea in the United States were highest between 1960 and 1975; in 1975, a national gonorrhea control program helped reduce the spread of the disease, and rates have been declining ever since. However, gonorrhea is still a public health problem: about 1 to 2 million cases of gonorrhea occur in the United States every year, although only a fraction of these will be detected and treated. The infection is highest in certain geographical areas or populations. Rates are highest in the South and in large cities throughout the U.S.; rates are also higher among adolescents and minority populations.

The large majority (over 80 percent) of cases occur in persons aged 15 to 29. The highest incidences among males occur between 20 to 24 years, and among females between 15-19 years. It is predominantly spread through the heterosexual population.

Gonorrhea is caused by the organism Neisseria gonorrhoeae, a gram negative diplococci and member of the Neisseria genus. It is a small obligate aerobe with flattened abutting sides. It is fast-growing, and divides by binary fission every 20 to 30 minutes. N. gonorrhoeae contains plasmids that produce beta-lactamase, and can result in penicillin resistance.

To grow N. gonorrhoeae, the specimen must be planted immediately on a selective medium such as the Thayer-Martin, a chocolate agar plate containing antibiotics. It grows best at 36 degrees centigrade in a 3 to 5 percent carbon dioxide environment. If the specimen is taken from a site that is somewhat sterile (such as cerebrospinal fluid or blood) the media should be chocolate without antibiotics.

Transmission of the bacteria between people occurs through vaginal or anal intercourse. Orogenital exposures are less efficient at spreading the bacteria. Perinatal transmission also occurs. Transmission from a woman to a man after one exposure is estimated to occur about 20 percent of the time. Passage of the infection from a man to a woman is estimated to be higher.

During transmission, the bacteria infect columnar epithelium and mucosal surfaces. The bacteria are ingested by pilli located on noncilliated epithelial cells. The incubation period of N. gonorrheae is 1 to 14 days, with an average of 3 to 7 days. During this time, the toxins damage the epithelial cells that N. gonnorheae produce, and a local, purulent infection occurs in the submucosa and luminal spaces. This process helps explain the symptoms the bacteria cause in humans.

The signs and symptoms of gonorrhea differ between men and women. For men, the majority will experience infection in their urethra, causing painful urination and discharge, usually pus from the penis. Some men will experience edema in the penis and lymphangitis, prostatitis, and epididymitis if their gonorrhea is untreated early. About 5 percent of men with the infection will not have a urethral infection and may experience only the complications of the disease later.

For women, gonorrhea may go undetected because only 50 to 80 percent of women experience symptoms once they are infected. Sometimes the symptoms, if experienced, may be so minimal that the woman may not choose to seek help. The endocervical canal is the most common site of infection in women, but the vast majority (70 to 90 percent) has colonization of the urethra in addition. Symptoms of these two sites of infection include painful urination, increased need to urinate, abnormal discharge from the vagina, abnormal uterine bleeding, or labial swelling. When the woman complains of extreme abdominal pain in addition to these symptoms it is possible that she has pelvic inflammatory disease (PID), in which the bacteria have infected her fallopian tubes and other reproductive organs. PID is a complication of untreated gonococcal infection, as is abscess of Bartholin's glands, perihepatitis, and, if the woman is pregnant, spontaneous abortion, premature delivery of an infant, and problems in the newborn including ophthalia neonatorum, vaginitis and urethritis.

Because complicated infections can cause scarring of reproductive tissue, untreated, complicated gonococcal infection can cause infertility.

Other sites of infection for both men and women include the anus and rectum, throat and eye. Anorectal infection will cause bleeding from the rectum, discharge and painful defecation. Pharyngeal, or throat, infections are largely asymptomatic but may present with a sore throat or pharyngeal exudates. Eye infections present with conjunctivitis.

Disseminated gonococcal infection can occur in both men and women, although it is extremely rare. Only 1 to 3 percent of the cases of gonorrhea result in disseminated infection. In disseminated infection the person may experience fever, arthritis, skin lesions, hepatitis, endocarditis and meningitis. Infants who are infected perinatally may show signs of disseminated infection through conjunctivitis, sepsis, arthritis and meningitis.

Up to 50 percent of people with gonorrhea also have chlamydial infections. Therefore, treatment for gonorrhea with an antibiotic should also include treatment for chlamydia with another, appropriate antibiotic.

A person who gets diagnosed with gonorrhea and receives an antibiotic must be sure to take all the antibiotics in the prescription. He or she then needs to return to a health care provider to get retested for the infection, just to ensure that it is not still present. Partners of the infected person should also go to their local health clinic to get tested for gonococcal infection.