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Lewis Liew Urology





What are STDs and how can their spread be prevented?

Sexually transmitted diseases (STDs) are infections that are transmitted during any type of sexual exposure, including intercourse (vaginal or anal), oral sex, and the sharing of sexual devices, such as vibrators. In the professional medical arena, STDs are referred to as STIs (sexually transmitted infections). This terminology is used because many infections are frequently temporary. Some STDs are infections that are transmitted by persistent and close skin-to-skin contact, including during sexual intimacy. Although treatment exists for many STDs, others currently are usually incurable, such as HIV, HPV, hepatitis B and C, and HHV-8. What is more, many infections can be present in, and be spread by, patients who do not have symptoms.

The most effective way to prevent the spread of STDs is abstinence. Alternatively, the diligent use of latex barriers, such as condoms, during vaginal or anal intercourse and oral-genital contact helps decrease the spread of many of these infections. Still, there is no guarantee that transmission will not occur. In fact, preventing the spread of STDs also depends upon appropriate counseling of at-risk individuals and the early diagnosis and treatment of those infected.


genital herpes

What is genital herpes and how is it spread?

Genital herpes is a viral infection that causes clear blisters that overlie ulcers on the skin or mucosa (lining of the body's openings) of sexually exposed areas. Two types of herpes viruses are associated with genital lesions; herpes simplex virus-1 (HSV-1) and herpes simplex virus-2 (HSV-2). HSV-1 more often causes blisters of the mouth area while HSV-2 more often causes genital sores or lesions in the area around the anus (perianal region).

Most people infected with HSV-2 have not been diagnosed as being infected. If symptoms occur, they appear approximately 3 to 7 days after an initial exposure to herpes. Many men experience mild symptoms, which resolve spontaneously. Others can develop severe bouts of painful blisters on the penis that can be accompanied by fever and headache. Once a herpes infection occurs, it is life-long and can be characterized by recurrent sporadic outbreaks. The outbreaks occur because the dormant HSV is activated. Outbreaks occur at different rates in different individuals. The recurrences can be associated with stress or other infections. They also occur with increased frequency in those who have weakened immune systems, such as with HIV infection. These outbreaks usually are characterized by mildly to moderately painful clusters of blisters over the infected area. The recurrences usually resolve spontaneously, with the blisters disappearing in about 5 days. HSV in HIV-infected individuals, however, can cause more severe disease, which often causes ulcers rather than blisters and persists for a longer time.

Estimates are that as many as 50 million persons in the United States are infected with genital HSV. Genital herpes is spread only by direct person to person contact. Again, most infected people have not been diagnosed. Most genital herpes is passed on by people who do not have active signs of disease at the time of transmission.


The suspicion for genital herpes is usually based upon the appearance of multiple, painful clusters of small blisters over the penis or anal area. The definitive diagnosis is based on a culture of the virus. The culture is done by opening a blister, swabbing the base of the ulcer, and sending the swabbed material to the laboratory for culture.

Blood tests that detect antibodies to the HSV reveal whether someone is infected with herpes. These antibodies are proteins that are produced by the body in an immunological (defensive) response specifically targeted against this virus. The antibodies, however, do not indicate whether the person's current lesions are actually due to the herpes or another disease. The antibody test, therefore, is of minimal value in diagnosing genital herpes.

What should persons infected with genital herpes know?

Patients who are newly diagnosed with genital herpes should be aware that
there is no cure for the infection,
recurrent episodes can occur, and
even when there are no obvious lesions, HSV can be spread to others.

Affected individuals should notify their sex partners that they are infected with HSV. They should avoid sexual activity not only when the blisters are present, but also when a pre-outbreak tingling, which sometimes is felt over the involved skin, occurs. Since HSV can be spread even during periods when there are no symptoms, condoms or other latex barriers should be used routinely during sexual contact with an infected person. This should be done even if the condoms are not needed at that time to prevent other STDs or to avoid pregnancy. Also, women with genital herpes should be aware of the possibility of that HSV can be spread to a newborn if the mother has an outbreak at the time of delivery. Finally, people with HSV infection should understand the clear, but limited role, of antiviral medications for the initial outbreak and for subsequent outbreaks and for suppressive therapy to prevent recurrences in patients with frequent outbreaks.


Several antiviral drugs have been used to treat HSV infection, including acyclovir, famciclovir, and valacyclovir. Although topical (applied directly on the lesions) agents exist, they are generally less effective than other medications and are not routinely used. Medication that is taken by mouth, or in severe cases intravenously, is more effective. Patients need to understand, however, that there is no cure for genital herpes and that these treatments only reduce the severity and duration of outbreaks. Since the initial infection with HSV tends to be the most severe episode, an antiviral medication usually is warranted. These medications can significantly reduce pain and decrease the length of time until the sores heal, but treatment of the first infection does not appear to reduce the frequency of recurrent episodes.

In contrast to a new outbreak of genital herpes, recurrent herpes episodes tend to be mild, and the benefit of antiviral medications is only derived if therapy is started immediately prior to the outbreak or within the first 24 hours of the outbreak. Thus, the antiviral drug must be provided for the patient in advance. The patient is instructed to begin treatment as soon as the familiar pre-outbreak “tingling” sensation occurs or at the very onset of blister formation.

Finally, suppressive therapy to prevent frequent recurrences may be indicated for those with more than 6 outbreaks in a given year.



Syphilis is an infection that is caused by a microscopic organism called Treponema pallidum . The disease can go through three active stages and a latent (inactive) stage. In the initial or primary stage of syphilis, a painless ulcer (the chancre) appears in a sexually-exposed area, such as the penis, mouth, or anal region. Sometimes, multiple ulcers may be present. The chancre develops any time from 10 to 90 days after infection, with an average time of 21 days following infection until the first symptoms develop. Painless, swollen glands (lymph nodes) are often present in the region of the chancre, such as in the groin of patients with penile lesions. The ulcer can go away on its own after 3 to 6 weeks, only for the disease to recur months later as secondary syphilis if the primary stage is not treated.

Secondary syphilis is a systemic stage of the disease, meaning that it can involve various organ systems of the body. In this stage, therefore, patients can initially experience many different symptoms, but most commonly they develop a skin rash that does not itch. Sometimes the skin rash of secondary syphilis is very faint and hard to recognize; it may not even be noticed in all cases. In addition, secondary syphilis can involve virtually any part of the body, causing, for example, swollen glands (lymph nodes) in the groin, neck, and arm pits, arthritis, kidney problems, and liver abnormalities. Without treatment, this stage of the disease may persist or resolve (go away).

Subsequent to secondary syphilis, some patients will continue to carry the infection in their body without symptoms. This is the so-called latent stage of the infection. Then, with or without a latent stage, which can last as long as twenty or more years, the third (tertiary) stage of the disease can develop. Tertiary syphilis is also a systemic stage of the disease and can cause a variety of problems throughout the body including: (1) abnormal bulging of the large vessel leaving the heart (the aorta), resulting in heart problems; (2) the development of large nodules (gummas) in various organs of the body; (3) infection of the brain, causing a stroke, mental confusion, meningitis (type of brain infection), problems with sensation, or weakness (neurosyphilis); (4) involvement of the eyes leading to sight deterioration; or (4) involvement of the ears resulting in deafness. The damage sustained by the body during the tertiary stage of syphilis is severe and can even be fatal.


A diagnosis of the chancre (primary stage of disease) can be made by examining the ulcer secretions under a microscope. A special microscope (dark field), however, must be used to see the distinctive corkscrew-shaped Treponema organisms. Since these microscopes are rarely detected, the diagnosis is most often made and treatment is prescribed based upon the appearance of the chancre. Diagnosis of syphilis is complicated by the fact that the causative organism cannot be grown in the laboratory, so cultures of affected areas cannot be used for diagnosis.

For secondary and tertiary syphilis, the diagnosis is based upon antibody blood tests that detect the body's immune response to the Treponema organism.

The standard screening blood tests for syphilis are called the Venereal Disease Research Laboratory (VDRL) and Rapid Plasminogen Reagent (RPR) tests. These tests detect the body's response to the infection, but not to the actual Treponema organism that causes the infection. These tests are thus referred to as non-treponemal tests. Although the non-treponemal tests are very effective in detecting evidence of infection, they can also produce so-called false positive results for syphilis. Consequently, any positive non-treponemal test must be confirmed by a treponemal test specific for the organism causing syphilis, such as the microhemagglutination assay for T. pallidum (MHA-TP) and the fluorescent treponemal antibody absorbed test (FTA-ABS). These treponemal tests directly detect the body's response to Treponema pallidum.

Patients with secondary, latent, or tertiary syphilis will almost always have a positive VDRL or RPR, as well as a positive MHA-TP or FTA-ABS. Several months after treatment, the non- treponemal tests will generally decrease to undetectable or low levels. The treponemal tests, however, will usually remain positive for the remainder of the patient's life whether or not they have been treated for syphilis.


Primary infection, secondary infection, or latent infection (for less than 1 year) is best treated with a single dose of Benzathine penicillin injection 2.4 million units. Patient who has penicillin allergy can be treated with Doxycycline 100 mg orally twice per day for 14 days or tetracycline 500 mg orally four times per day for 14 days.



Common causes and symptoms

The urethra is a canal in the penis through which urine from the bladder and semen are emptied. Urethritis (inflammation of the urethra) in men begins with a burning sensation during urination and a thick or watery discharge that drips from the opening at the end of the penis. Infection without and symptoms is common. The most common causes of urethritis are the bacteria Neisseria gonorrhea and Chlamydia trachomatis. Both of these infections are usually acquired through sexual exposure to an infected partner. The urethritis can extend to the testicles (orchitis) and the tube connecting the testicles to the urethra, the epididymis (epididymitis). These complicated and potentially severe infections can cause tenderness and pain in the testicles. For example, they occasionally develop into an abscess (pocket of pus) requiring surgery and can even result sterility.


A person with symptoms of urethritis as described above should seek medical care. An evaluation for urethritis generally requires a laboratory examination of a sample of urethral discharge or of a first-in-the-morning urine sample. The specimens are examined for evidence of inflammation (white blood cells). Urethritis has traditionally been classified into two types: gonococcal (caused by the bacterium responsible for gonorrhea) and non-gonococcal. Chlamydia is the major cause of non-gonococcal urethritis. If evidence of urethritis is present, every effort should be made to determine if it is caused by Neisseria gonorrhea, Chlamydia trachomatis, or both. Several diagnostic tests are currently available for identifying these organisms, including cultures of the urethral discharge (obtained by swabbing the opening of the penis with a cotton swab) or of the urine. Other tests rapidly detect the genetic material of the organisms. Ideally, treatment should be directed towards the cause of infection.

If appropriate and timely follow-up is impossible on the patient's part, however, patients should be treated for both N. gonorrhea and C. trachomatis as soon as urethritis is confirmed, because these organisms commonly occur in the same people, produce similar symptoms, and can cause serious complications if left untreated.



Chlamydia is an infection caused by the bacterium Chlamydia trachomatis that most often occurs in sexually active adolescents and young adults. It can cause urethritis and the resultant complicating infections of epididymitis and orchitis. Recent studies have proven, however, that both infected men and infected women commonly lack symptoms of chlamydia infection. Thus, these individuals can unknowingly spread the infection to others. Consequently, sexually active individuals should be routinely evaluated for chlamydial urethritis. Note that another strain (type) of Chlamydia trachomatis, which can be distinguished in specialized laboratories, causes LGV (see above).


A convenient single dose therapy for chlamydia is azithromycin (Zithromax) 1 gram by mouth. Alternative treatments are often used, however, because of the high cost of this medication. The most common alternative treatment is doxycycline 100 mg twice per day for 7 days taken by mouth. Patients should abstain from sex for 7 days after the start of treatment and to notify all of their sexual contacts. People with chlamydia are often infected with other STDs and therefore should undergo testing for other infections that may be present at the same time. Their sexual contacts should also then be evaluated for chlamydial infection.

The most common reason for the recurrence of chlamydia infection is the failure of the partners of infected persons to receive treatment. The originally infected person then becomes reinfected from the untreated partner. Other reasons are the failure to correctly follow one of the 7-day treatment regimens or the use of erythromycin for treatment, which has been shown to be somewhat less effective than azithromycin or doxycycline. Complicated chlamydial infections, epididymitis, and orchitis are generally treated with a standard single-dose therapy as used for Neisseria gonorrhea (described below) and 10 days of treatment for Chlamydia trachomatis with doxycycline. In this situation, a single dose therapy for chlamydia is not an option.

What should a person do if exposed to someone with Chlamydia?

Persons who know that they have been exposed to someone with chlamydia should be evaluated for the symptoms of urethritis and tested for evidence of inflammation and infection. If infected, they should be treated appropriately. Many doctors recommend treating all individuals exposed to an infected person if the exposure was within the 60 days preceding the partner's diagnosis.



Gonorrhoea is an STD that is caused by the bacteria Neisseria gonorrhoea. In women, this infection often causes no symptoms and can therefore often go undiagnosed. In contrast, men usually have the symptoms of urethritis, burning on urination, and penile discharge. Gonorrhoea can also infect the throat (pharyngitis) and the rectum (proctitis). Proctitis results in diarrhea (frequent bowel movements) and an anal discharge (drainage from the rectum). Gonorrhoea can also cause epididymitis and orchitis. What is more, gonorrhoea can cause systemic disease (throughout the body) and most commonly results in swollen and painful joints or skin rash. Many patients with gonorrhoea also are infected with Chlamydia.

Symptoms of gonorrhoea usually develop in men within 4 to 8 days after genital infection, although in some cases they may occur after a longer time period.


Gonorrhoea may be diagnosed by demonstration of the characteristic bacteria when urethral secretions are examined microscopically. Gonorrhoea can also be diagnosed by a culture from the infected area, such as the urethra, anus, or throat. In patients with systemic gonorrhoea with, for example, arthritis or skin involvement, the organism can occasionally be cultured from the blood. Newer, rapid diagnostic tests that demonstrate the genetic material of N. gonorrhoea are also available.


The treatment of uncomplicated gonorrhoea affecting the urethra or rectum is usually a single-dose injection of ceftriaxone 125 mg. Alternative treatments include oral doses of cefixime (Suprax) 400 mg, ciprofloxacin (Cipro) 500 mg, ofloxacin (Oflox) 400 mg, cefpodoxime 400 mg, or levofloxacin 250 mg daily. An intramuscular injection of 2 g of spectinomycin is also an alternative treatment.

Many patients with gonorrhoea are simultaneously infected with chlamydia. Patients treated for gonorrhoea, therefore, should also be treated for chlamydia with a single dose of azithromycin 1 gram or doxycycline 100 mg twice per day for 7 days, both of which are taken by mouth.

Systemic gonorrhoeal infections involving the skin and/or joints is generally treated with either daily injections of ceftriaxone 1 gram in the muscle tissue (intramuscularly) or in the vein (intravenously) every 24 hours, or cefotaxime or ceftizoxime 1 gram intravenously every 8 hours. If the patient does not need admission to the hospital or is stable enough for discharge, the treatment can be one of the quinolone antibiotics (ciprofloxacin 500 mg twice per day orofloxacin 400 mg once daily) for 14 days, along with the treatment for Chlamydia. Another option for the treatment of disseminated (throughout the body) gonococcal infections is spectinomycin 2 g intramuscularly every 12 hours.

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