Tag Archives: cefixime

STD Awareness: Gonorrhea’s Ever-Growing Resistance to Antibiotics

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Gonococci, the bacteria that cause gonorrhea.

Ever since the advent of effective antibacterial therapies less than a century ago, humans with access to these drugs can easily cure gonorrhea. Most of us in the developed world have forgotten that this disease was once a leading cause of infertility in women and blindness in babies — sulfa drugs and antibiotics not only erased these infections from our bodies, they also erased memories of gonorrhea’s dangers from our collective consciousness.

There are two drugs remaining to treat gonorrhea, and resistance to them is climbing higher as the years march on.

Unfortunately, thanks to their talent for genetic gymnastics, gonococci, the bacteria that cause gonorrhea, have been evolving resistance to every drug we’ve thrown at them — to tetracycline, to penicillin, and more recently to fluoroquinolones. One class of antibiotics remains to treat gonorrhea: cephalosporins. In 2013, Centers for Disease Control and Prevention (CDC) Director Tom Frieden warned that we could find ourselves in a “post-antibiotic era” – unless we take precautions. And, just two weeks ago, the latest study from the CDC’s Gonococcal Isolate Surveillance Project sounded the alarm that the post-antibiotic era is drawing ever closer, especially when it comes to gonorrhea.

Azithromycin and ceftriaxone, the two drugs that are used in combination to deliver a one-two punch to invading gonococci, are the best antibiotics remaining in our arsenal. Azithromycin is taken by mouth, while ceftriaxone is administered by a shot, and when taken together they team up to target different weak points in gonococci’s armor. Azithromycin interferes with the bacteria’s ability to make proteins, shutting the cells down, while ceftriaxone causes the cell wall to fall apart. However, the gonococci can acquire resistance. For example, in the case of azithromycin, a resistant bacterium can spit out the drug before it has a chance to kill it, or it can change the shape of its protein-making apparatus such that the drug can’t attach to it.  Continue reading →

STD Awareness: Which STDs Are Resistant to Antibiotics?

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You’ve probably heard of MRSA, which is pronounced “mersa” and stands for methicillin-resistant Staphylococcus aureus — a strain of bacteria that is resistant to methicillin, as well as pretty much every other antibiotic out there. MRSA is an example of evolution by natural selection — what didn’t kill its ancestors made them stronger, spawning a drug-resistant strain.

There are drug-resistant strains of gonorrhea, trichomoniasis, and syphilis.

Evolution is the force behind life’s diversity. Normally, diversity is a good thing — but when it comes to microbes that cause diseases like gonorrhea, trichomoniasis, and syphilis, these organisms’ ability to evolve new defenses against our antimicrobial drugs isn’t good for us.

STDs have plagued us for millennia, but it wasn’t until the 20th century that we finally developed antibiotics, which gave us a powerful tool against many of our most formidable sexually transmitted foes. Suddenly, scourges like gonorrhea and syphilis could be quickly and easily treated with a dose of penicillin.

Problem solved, right? Nope. Enter evolution by natural selection. Continue reading →

STD Awareness: Ceftriaxone-Resistant Gonorrhea

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Nestled in the throat of a Japanese woman was a collection of clones that scientists abducted from their temporary habitat and christened H041 — a humdrum moniker for a strain of bacteria that would burn headlines in medical journals. Though the bacteria never caused symptoms in their host, they lingered in her throat from at least January until April of 2009, when a swab finally tested negative. Rather than succumbing to repeated bombardment by an antibiotic called ceftriaxone, the infection probably just went away on its own — as oral gonorrhea infections tend to do.

Resistance to ceftriaxone, our last good gonorrhea drug, has been reported in Japan, Australia, Sweden, France, and Spain.

The emergence of antibiotic-resistant gonorrhea is considered one of the most pressing problems in infectious disease — just two years ago, the Centers for Disease Control and Prevention named it an “urgent threat.” We have one remaining first-line gonorrhea treatment left: extended-spectrum cephalosporins, which include cefixime, which is taken orally, and ceftriaxone, which is administered as a shot. Resistance to cefixime was first documented in 1999, leaving ceftriaxone as our best remaining option, and the CDC’s first choice for treating gonorrhea. There are no good alternatives to ceftriaxone remaining, which is why reports of ceftriaxone-resistant gonorrhea are so deeply troubling.

What made H041 special was that it was the first extensively drug-resistant strain of Neisseria gonorrhoeae, the bacteria that cause gonorrhea. With an unusually high level of resistance to ceftriaxone — four to eight times higher than the previous record holder — the strain was also resistant to a slew of other antibiotics: penicillin and its relatives, fluoroquinolones, macrolides, tetracycline, trimethoprim-sulfamethoxazole, chloramphenicol, nitrofurantoin, cefpodoxime, cefixime, ciprofloxacin, and levofloxacin — and had reduced susceptibility to azithromycin to boot.

Another thing that made H041 special — as special as clones can be, anyway — is that it never reappeared. After its discovery, researchers in Kyoto and Osaka intensified their surveillance, trying to uncover it again and track its spread through the population. However, their search for H041 turned up empty handed. But other ceftriaxone-resistant strains have been documented around the world. Continue reading →

STD Awareness: Genetics and the Gonococcus

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Image: CDC

Ever since the discovery of effective antibacterial therapies less than a century ago, humans have been able to easily cure gonorrhea, the sexually transmitted scourge that laid waste to fallopian tubes and robbed newborns of vision. Most of us in the developed world have forgotten that this disease was once a leading cause of infertility in women and blindness in babies — and still is in much of the developing world.

Unfortunately, gonococci — the species of bacteria that cause gonorrhea — have been evolving resistance to every antibiotic we’ve thrown at them, including sulfonamides, penicillins, tetracyclines, macrolides, fluoroquinolones, and narrow-spectrum cephalosporins. We have one remaining first-line gonorrhea treatment left: extended-spectrum cephalosporins, which include cefixime, which is taken orally, and ceftriaxone, which is administered as a shot — and resistance is emerging to those drugs, as well.

Gonococci don’t swap potato salad recipes at family reunions — they swap genetic material!

The emergence of antibiotic-resistant gonorrhea is considered one of the most pressing problems in infectious disease — just two years ago, the Centers for Disease Control and Prevention named it an “urgent threat,” and indeed, gonorrhea seems to be evolving resistance to drugs at quite a rapid clip. Gonococci can acquire resistance to antibiotics in three ways.

First, a genetic mutation can endow bacteria with special antibiotic-fighting powers, making it harder for a drug like penicillin to attach to their cells and destroy them. Such a mutant is more likely to gain evolutionary traction if it finds itself in an antibiotic-drenched environment in which resistance to that drug allows it to “outcompete” other bacteria. Indeed, antibiotic resistance was first documented in the 1940s, just years after sulfonamides and penicillin were introduced as the first effective cures for gonorrhea. Continue reading →

STD Awareness: The Latest on Gonorrhea

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Neisseria gonorrhoeae, the bacterium that gangs up on your body to give it gonorrhea. Image: CDC

Gonorrhea is that guy with the funny name who’s always up to something new and mischievous. Last year, the New England Journal of Medicine declared that it’s “time to sound the alarm” in response to emerging strains of gonorrhea that are increasingly resistant to antibiotics. Then, earlier this year, the medical journal JAMA reported the first North American sightings of gonorrhea that failed treatment with cefixime, one of the last drugs we have in our anti-gonorrhea arsenal. It’s a great time to be a gonococcus — the type of bacteria that causes gonorrhea — but the humans they infect probably don’t see it that way.

Last month, this bad boy rose to the top of the Most Wanted list when the Centers for Disease Control and Prevention proclaimed antibiotic-resistant gonorrhea an “urgent threat” — the highest threat level, which gonococci share with only two other bacteria types. To give you some context, the much more famous superbug MRSA was categorized as a “serious” threat, one notch below “urgent.”

Antibiotic-resistant gonorrhea is an “urgent” threat; meanwhile, researchers develop a gonorrhea vaccine that works — on mice.

Antibiotic-resistant gonorrhea is especially insidious for two reasons. One, gonorrhea often doesn’t have symptoms, which allows it to jump from one sexual partner to another, the hosts often none the wiser. Two, unless health care providers actually test the bug’s DNA, they have no way of knowing whether or not they’re dealing with a drug-resistant strain. This opens up the possibility for treatment failure — and for the antibiotic-resistant bacteria to be further propagated into the community.

The CDC estimates that the United States sees 246,000 cases of antibiotic-resistant gonorrhea infections annually — that’s about 30 percent of all gonorrhea infections in the country. For now, we seem to be able to cure them with higher doses or different combinations of drugs. So why does antibiotic-resistant gonorrhea deserve the “urgent” designation? While gonorrhea isn’t associated with a body count — unlike other drug-resistant pathogens, which collectively kill at least 23,000 Americans a year — it can have terrible consequences. Gonorrhea can cause pelvic inflammatory disease (PID) when it advances up the female reproductive tract, and epididymitis when it invades the male reproductive tract; both conditions can cause infertility. Also, gonorrhea infections make us more vulnerable to HIV. The CDC estimates that if the most resistant gonorrhea strain gains ground over the next decade, the country could see an additional 75,000 cases of PID, 15,000 cases of epididymitis, and 222 HIV infections, costing us $235 million. Continue reading →

STD Awareness: Will Gonorrhea Be Worse Than AIDS?

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A scanning electron micrograph of a colony of Neisseria gonorrhoeae, the bacteria that cause gonorrhea. Image: Portland State University

If you’ve been reading the news lately, you might have noticed an odd piece of reportage from CNBC, in which a naturopath claimed that antibiotic-resistant gonorrhea “might be a lot worse than AIDS” and might cause cases of sepsis that could kill “in a matter of days.” This quotation, uttered by a single naturopath, was then exaggerated in sources such as the United Kingdom’s Daily Mail, which ran the headline “Doctors warn that antibiotic-resistant strain of gonorrhea could be ‘worse than AIDS.'” In fact, the only person making this claim was one naturopath, not a doctor, and certainly not plural “doctors.”

There’s a lot to unpack here. First is the alarmism in the original CNBC article, and its dependence on an unreliable source. Second is the issue of antibiotic-resistant gonorrhea itself, which is a very serious public health problem. Thirdly, let’s look at the naturopath’s claim, which is that antibiotic-resistant gonorrhea could unleash a plague worse than AIDS and kill its victims in a matter of days.

Claims that antibiotic-resistant gonorrhea will be “worse than AIDS” are greatly exaggerated.

Alan Christianson, the naturopath behind the hyperbolic claims of super-virulent gonorrhea, does not seem to be an actual expert in infectious disease (his website lists “natural endocrinology” and “male menopause” among his specialties), nor is he a medical doctor. The article identifies him as a “doctor of naturopathic medicine,” but what does that mean?

Naturopaths are not medical doctors, and degrees in naturopathic medicine aren’t awarded by institutions accredited by the Association of Medical Colleges, the body that accredits medical schools. Naturopathy is a philosophy that is not generally supported by scientific evidence, but rather is based in “a belief in the healing power of nature,” according to the National Center for Complementary and Alternative Medicine. It was developed in the 1800s and today encompasses many modalities of alternative medicine, including homeopathy and herbalism. For these reasons, it is odd that a journalist quoted a naturopath on the potential of antibiotic-resistant gonorrhea rather than someone more qualified, such as a microbiologist or epidemiologist. Continue reading →

STD Awareness: An Update on Antibiotic-Resistant Gonorrhea

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Last year, we shared the fascinating and frightening story of the emergence of increasingly antibiotic-resistant gonorrhea, an STD caused by the gonococci bacteria. The sexually transmitted scourge, which we only so recently reined in with the development of antibiotics, has been performing some genetic gymnastics to defeat almost every drug we’ve thrown at it. We douse it with certain drugs, and the bacterium literally spits them back out at us, and it inactivates other drugs by snapping the active molecules in half. Sulfa drugs, penicillins, tetracyclines, fluoroquinolones — they all make a gonococcus heave a bored sigh. Luckily, cephalosporins were still an effective treatment, but recently there have been reports of stubborn gonorrhea infections caused by the latest and greatest (and some might say most hated) strain of gonococci.

The bacteria that cause gonorrhea continue to evolve, right under our noses!

Well, the story isn’t over — just like the bacteria that cause gonorrhea, the tale is rapidly evolving. The latest class of antibiotics that the gonococci are chipping away at is the cephalosporin family, which includes several chemically related drugs that work in similar ways — and that can likewise be defeated by microbes in similar ways. Cephalosporin-resistant gonorrhea was first reported in Japan and documented in a few European countries. The Japanese case that inspired the New England Journal of Medicine to declare last year that it was “time to sound the alarm” was an oral gonorrhea infection that was resistant to one member of the cephalosporin family: ceftriaxone.

Earlier this month, the prestigious medical journal JAMA reported the first North American sightings of gonorrhea that failed treatment with another cephalosporin: cefixime. Yeah, I know, you’d rather hear about Big Foot or UFO sightings, not evidence that something as real and unmythical as Gonorrhea 5.0 has landed in your back yard. Luckily, there’s plenty you can do to protect yourself from it, and we’ll tell you all about it toward the end of this article. (Spoiler alert: It involves using condoms!) Continue reading →