Antibiotic Resistance in Syphilis

Scanning Electron Micrograph of Syphilis Bacteria. CDC/SCIENCE PHOTO LIBRARY/GETTY IMAGES

Much of the time, when doctors are talking about the problem of antibiotic resistance in STDs, they're talking about gonorrhea. Antibiotic resistant gonorrhea is a growing problem throughout the world, and a problem of which doctors and researchers are becoming increasingly aware and concerned. However, gonorrhea isn't the only STD where resistance is showing up as a potential problem. It's not even the only bacterial STD, as there are growing concerns about antibiotic resistance in syphilis.

Syphilis is a bacterial STD caused by Treponema Pallidum, a spiral shaped bacterium. Detected using VDRL tests, it can have serious long term side effects if left untreated, it can even be fatal. One of the reasons syphilis is often talked about in academic settings is its role in upending the way that clinical trials are performed in the United States, due to the ethical malfeasance of the doctors behind the Tuskegee Study. However, in recent years there have also been renewed conversations about clinical concerns about the infection -- such as its potential spread during oral sex and the growing problem of antibiotic resistance. 

Although injections of penicillin are the preferred treatment for syphilis in the United States, other countries have used alternate antibiotics for treatment, due to problems with allergies, ease of administration, and reduced cost. However, there has been a growing problem of antibiotic resistance to azithromycin, which is why that antibiotic is not currently recommended for syphilis treatment in the U.S.

This can necessitate retesting of patients with syphilis due to concerns about treatment failures, not to mention re-treatment. Both re-testing and re-treatment have the potential to put significant burden on patients, even aside from increasing the cost of care.

As with gonorrhea, most cases of syphilis remain treatable -- if not always easily or cheaply.

However, the problem of antibiotic resistance remains one to watch. After all, the problem of syphilis had been thought to be under control for many years before it's resurgence in gay men - a resurgence linked to the low HIV risk associated with oral sex, and many people's incorrect assumption that oral sex is therefore safe.

Antibiotic resistant syphilis isn't yet a major concern in the United States, and due to the relatively easy accessibility and affordability of penicillin in the country, hopefully it won't ever be. However, it is something to keep an eye on around the world, as uncontrolled syphilis infections can cause serious problems for vulnerable populations -- those who have difficulty accessing testing and treatment and, in particular, their unborn children.


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