Sexually Transmitted Diseases in Women

Sexually transmitted diseases (STDs) are among the most common infectious diseases in the United States today. More than 20 STDs have been identified and they affect an estimated 19 million men and women in this country each year. The annual treatment cost of STDs in the United States is estimated to be more than $14 billion.

How do STDs affect women?

Health problems caused by STDs tend to be more severe and more frequent for women than for men, in part because for women there are often no visible symptoms, so they do not seek care until serious problems have developed.

Some STDs can spread into the uterus (womb) and fallopian tubes to cause pelvic inflammatory disease (PID), which is a cause of both infertility and ectopic (tubal) pregnancy. Ectopic pregnancy can be fatal. STDs in women also may be associated with cervical cancer. Human papillomavirus infection (HPV) can cause genital warts and cervical and other genital cancers. STDs can be passed from a mother to her baby before, during or immediately after birth. Some of these new-born infections can be cured easily, but others may cause a baby to be permanently disabled or even die.

What are the most common types of STDs?

Chlamydial Infection

This infection is the most common of all bacterial STDs, with an estimated 2.8 million new cases occurring each year. Chlamydial infection may cause an abnormal vaginal discharge and burning during urination. In women, untreated chlamydial infection may lead to pelvic inflammatory disease (PID), one of the most common causes of ectopic pregnancy and infertility in women. Many people with chlamydial infection, however, have few or no symptoms of infection; it often goes undiagnosed and untreated. Once diagnosed with chlamydial infection, a person can be treated with an antibiotic.

Genital Herpes

Genital herpes affects at least 45 million Americans ages 12 and older. Approximately 500,000 new cases of this incurable viral infection develop annually. Herpes infections are caused by the herpes simplex viruses type 1 and type 2. Most genital herpes is caused by HSV-2. Most individuals have no or only minimal signs or symptoms. When signs do occur, they typically appear as one or more blisters on or around the genitals or rectum. The blisters break, leaving tender sores that may take two to four weeks to heal the first time they occur. Typically, another outbreak can appear weeks or months after the first, but it almost always is less severe and shorter. The virus remains in the body for life and the lesions may recur from time to time. Severe or frequently recurrent genital herpes is treated with one of several antiviral drugs that are available by prescription. These drugs help control the symptoms, but do not eliminate the herpes virus from the body. Suppressive antiviral therapy can be used to prevent recurrences and perhaps transmission. Women who acquire genital herpes can transmit the virus to their babies during delivery. Untreated HSV infection in new-borns can result in mental retardation and death.

Genital Warts 

Genital warts (also called venereal warts or condylomata acuminata) are caused by the human papillomavirus, a virus related to the one that causes common skin warts. Certain high-risk types of HPV can cause cervical cancer and other genital cancers, but these are different from the types that cause genital warts. Genital warts usually first appear as small, hard painless bumps in the vaginal area or around the anus. If untreated, they may grow and develop a fleshy, cauliflower-like appearance. There is a very low risk that a pregnant woman with genital warts can pass HPV to her baby. In the rare cases where HPV is passed, the baby could develop warts in the throat or voice box. Genital warts infect between 500,000 to 1 million Americans each year. They are usually removed by freezing, burning or laser treatment. If the warts are very large, they can be removed by surgery. If they recur, they may be treated with injections of a type of interferon. Although treatments may get rid of warts, they do not get rid of HPV, which can still be passed on to sex partners.

Gonorrhea

Gonorrhea is the second most commonly reported infectious disease in the United States. The CDC estimates that more than 700,000 persons in this country get new gonorrheal infections each year; only about half of these infections are reported to the CDC. Most women who are infected have no symptoms. Even when a woman has symptoms, they can be so non-specific as to be mistaken for a bladder or vaginal infection. The most common symptoms of gonorrhea are a vaginal discharge or vaginal bleeding between periods. Untreated cases can lead to serious complications, including PID, ectopic pregnancy and infertility. Historically, penicillin has been used to treat gonorrhea, but in the last decade resistance to penicillin has emerged. New antibiotics or combinations of drugs must be used to treat these resistant strains.

Syphilis 

While the rate of primary and secondary (P&S) syphilis – the most infectious stages of the disease – reached an all-time low in 2000, it has increased dramatically in recent years. Between 2004 and 2005, the number of reported P&S syphilis cases in the United States increased from 7,980 to 8,724. The overall increase in syphilis cases was driven primarily by increases among males. However, troubling trends also were seen among females, as the rate of reported cases among females increased for the first time in more than 10 years. Syphilis is easily curable in its early stages. The initial symptom is a chancre, a painless open sore that usually appears around or in the vagina. If untreated, it can lead to serious long-term complications, including problems of the heart and central nervous system, organ damage and even death. Congenital syphilis can cause stillbirth, death soon after birth, and physical deformity and neurological complications in children who survive. The full course of the disease can take years. Penicillin remains the most effective drug in the treatment of syphilis.

Other STDs

Other diseases that may be sexually transmitted include human immunodeficiency virus (HIV), trichomoniasis, bacterial vaginosis, cytomegalovirus infections and pubic lice (crabs). STDs in pregnant women are associated with a number of adverse outcomes, including spontaneous abortion and infection in the new-born. Low birth weight and prematurity appear to be associated with STDs, including chlamydial infection and trichomoniasis. Congenital or perinatal infection (infection that occurs around the time of birth) occurs in 30 percent to 70 percent of infants born to infected mothers, and complications may include pneumonia, eye infections, and permanent neurologic damage.

What can you do to prevent STDs?

The best way to prevent STDs is to avoid sexual contact with others. If you decide to be sexually active, there are things that you can do to reduce your risk of developing an STD:

Have a mutually monogamous sexual relationship with an uninfected partner.

Use condoms correctly every time you have sex. The use of latex or polyurethane condoms during vaginal intercourse, when used consistently and correctly, can reduce the risk of transmission of STDs.

Delay having sexual relations as long as possible. The younger people are when having sex for the first time, the more susceptible they become to developing an STD. The risk of acquiring an STD also increases with the number of partners over a lifetime.

Source: http://www.idph.state.il.us/about/womenshealth/factsheets/std.htm

NUCLEIC-ACID AMPLIFICATION TESTS

NUCLEIC-ACID AMPLIFICATION TESTS

Nucleic-acid amplification tests, also known as NATs or NAATs, are used to identify small amounts of DNA or RNA in test samples. When it comes to STD testing, there are NATs available that can detect a variety of different STDs. In fact, most urine tests for STDs are performed using nucleic-acid amplification tests.

MECHANISM

A NAT uses a series of repeated chemical reactions to make numerous copies of the DNA or RNA that doctors are trying to detect. These reactions amplify the signal of the nucleic acids in the test sample so that they are easier to identify. It's much simpler to find 10,000 copies of a gene than 10. 

once the amount of DNA or RNA has been increased in the sample using PCR or LCR, more conventional tests are used to detect it. These tests usually involve some form of nucleic acid hybridization. In those tests, the sample is probed with an artificially produced complementary strand of DNA or RNA that has been labelled in some way that makes it easy to detect. It may help to picture it as a glow in the dark tag that only sticks to one very specific piece of identifying information.

STD TESTING

Nucleic-acid amplification tests are incredibly useful for STD testing. They allow doctors to detect an STD pathogen even when only a very small number of organisms are present. It is this sort of technology that has made it possible to do urine testing for STDs that were previously only detectable by swab.

Furthermore, since nucleic-acid amplification tests are incredibly sensitive to even small amounts of viral DNA, they are very important for screening the blood supply. These tests make it possible to detect tiny amounts of HIV and other blood-borne pathogens that might otherwise be missed.

There are also non-amplified nucleic acid tests available for certain STDs, such as gonorrhea and chlamydia. Non-amplified nucleic acid hybridization tests are more likely to be used when large amounts of bacterial or viral DNA (or RNA) would be expected to be present, such as in a urethral swab or in a bacterial culture sample. In such circumstances, no amplification is necessary. In these samples, if DNA or RNA is present, it should be present in detectable amounts.

Call for abstracts: https://std-hiv-aids.cmesociety.com/call-for-abstracts

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No more ‘sledgehammer’: As gonorrhea grows resistant to antibiotics, researchers look to bespoke treatments

With antibiotic resistance on the rise, the days when doctors and clinics could rely on one treatment to cure all gonorrhea cases may be waning.

In fact, clinicians may find that some of their patients respond best to drugs of the past. But how will they know which patients?

To answer that question, a handful of researchers and companies are trying to develop rapid, point-of-care diagnostics that would signal which drugs work for a given patient and permit clinicians to tailor treatment to the bacterial strain. A future, in other words, of bespoke treatment, in which a greater variety of drugs are used to treat a very common sexually transmitted disease — potentially prolonging the utility of several antibiotics.

“It would allow for smarter medicine,” Dr. Jeffrey D. Klausner, a professor of infectious diseases medicine at the University of California, Los Angeles, told STAT. “Right now, we’re treating gonorrhea with a sledgehammer, we’re treating everything with the same exact regime. And it’s not a surprise that the organism will become resistant to what we’re currently using.”

Klausner has collaborated with several companies working in this area but has not received payment from the companies. The companies have made contributions to UCLA, he said.

Gonorrhea is spread by sexual contact, and infection can occur in the genitals, the rectum, and the throat. The World Health Organization estimates that about 78 million people a year are infected with gonorrhea; roughly 820,000 of those infections occur in the United States.

Left untreated, gonorrhea can cause pelvic inflammatory disease and infertility in women and sterility in men. Infection increases a person’s risk of contracting HIV. Babies born to an infected woman can develop blindness.

From a treatment point of view, the ideal regimen for curing gonorrhea is an oral antibiotic — and was long the standard of care. But gonorrhea is a wily bacterium, adept at learning tricks that allow it to evade the power of antibiotics. One after another, the available drugs have started to fail.

For several years, the recommended regimen for gonorrhea has been a dual-therapy approach, the thinking being that it is harder for resistance to develop to a drug combination than to a single drug. The current recommended therapy is one injection of the antibiotic ceftriaxone followed by a multiday course of azithromycin. But even that approach is starting to show signs of weakness.

At the same time, there has been a belief that, even as medicine has moved on, there is life left in the drugs that have been abandoned — if you could figure out in whom they would work.

“We’ve been treating empirically and a lot of times ignoring the fact that the majority of organisms, the majority of infections we’re seeing, are actually fully susceptible to the old drugs,” said Fred Tenover, vice president for scientific affairs at Cepheid Inc., a California-based maker of molecular diagnostics.

“So now we have to have a change in philosophy and say: You know what? Now it’s time to go and do what we do for every other infection, which is actually define what the best therapeutic is up front.”

Cepheid is exploring the idea of developing such a test, Tenover said. “We’re trying to figure out what it would look like and what it would cost,” he said. “This is not in our pipeline officially. It’s something we’re looking at, something we haven’t committed to, but we have figured out how to make the assay.”

Other smaller companies are in the hunt. SpeeDx, an Australian-American firm, has a test in development that it hopes will receive licensing approval in Europe this autumn. The company is currently conducting a clinical trial in the United States in hopes of with the goal of filing for approval with the Food and Drug Administration.

The test both diagnoses gonorrhea and indicates whether the infecting strain can be treated with Cipro, said CEO Colin Denver. It currently would need to be processed by a central lab, but the plan is to develop the assay as a point-of-care test that could be used in a clinic or doctor’s office.

Shield Diagnostics, of Santa Clara, Calif., has a similar idea in mind. The company has a proprietary testing platform; CEO Fred Turner said it will roll out its first test this fall. The test can diagnose gonorrhea and ascertain if the strain is susceptible to Cipro.

For now, it is not a point-of-care test; that may be three or four years down the road, Turner said. In the meantime, Shield will process the tests in its own laboratories. Turner said the testing will likely take two to three days. Ideally, over time, both companies hope their assays will be expanded to give a broader resistance profile, one that indicates whether other drugs would be effective.

“Our ultimate goal is to have clinicians utilize a test-and-treat algorithm so that you don’t have to use these empiric therapies,” Denver said.

A patient would come into a clinic and specimens to test would be taken. While he or she is seeing the doctor, the test would be run. Within an hour or so, the doctor would know whether a single dose of Cipro or cefixime (also an oral drug) would do, or whether the ceftriaxone-azithromycin combination would be the better option.

“It’s like personalized medicine — your individual infection treated with the antibiotic you know is going to work,” Denver said.

But in order for these types of tests to be truly useful, they’ll need to be affordable and produce a rapid answer, said Dr. Lindley Barbee, an assistant professor of infectious diseases at the University of Washington and medical director of the Public Health – Seattle & King County STD Clinic. Not a day or two later, but while the person was in the clinic.

Many clinics that treat sexually transmitted infections are government funded, Barbee noted: “You have to get the cost low enough to make it worthwhile.”

That’s clearly a factor that has slowed development of these tests. “If you say to somebody who’s paying $10 for this test now, ‘Well, I can better define your therapy but it’s going to cost $17 a test, not $10 a test,’ that may be beyond the reach of a lot of public health clinics or STI clinics. And that’s probably what it would take,” said Cepheid’s Tenover.

“To date the return on investment has not been positive enough to make these commercially available,” he said. “That may be changing. And I think as we talk more and more about the spread of superbug gonorrhea, people may be more and more interested in doing this. But in the past there hasn’t been a market for these types of tests.”

Source: https://www.statnews.com/2018/07/17/gonorrhea-grows-resistant-to-antibiotics-researchers-look-to-bespoke-treatments/