Tag Archives: antibiotics

Unusual Treatments For A Gastrointestinal Illness

Intestinal flora are microbes living in every human being's digestive tract that do the grunt work of digestion; they play an important role in breaking down the food people eat. These microbiota are also a part of the immune response, helping the immune system learn to properly distinguish friend from foe. One type of these microbes is a bacterium called Clostridium difficile. Normally, there is only a small population of this bacterium in the gut. When, however, other gut microflora are reduced or eliminated, typically by antibiotics, C. diff can get out of control, growing unchecked and causing serious illness. Symptoms of this include watery diarrhea, fever, and nausea. In some cases, a C. diff infection can result in colitis.

It can also result from colitis, as inflammatory bowel disease can trigger a C. diff infection. Abdominal or gastrointestinal surgery is another possible cause, particularly in patients who have experienced an infection already. A type of drug called a proton pump inhibitor is often prescribed for chronic indigestion, GERD, and other conditions; it can also make someone more prone to C. diff infection. Suppressing the immune system, such as through chemotherapy, also raises the risk.

The standard treatment for C. diff infection is easily administered and when it works—90 percent of the time—it works quickly and with no side effects. Despite this, the treatment sounds unappealing: fecal transplant. The microbes in the donated matter replace the gut flora the patient had lost, recolonizing the intestine and taking it back from C. diff. Recently, researchers have been looking for a synthetic substitute. Not just a joke-shop novelty, the synthetic version avoids the problem of pathogens from the donor being acquired by the recipient, as well as overcoming the aesthetic objection.

Another possible treatment being investigated involves llamas. A group of Canadian scientists who are studying llamas say they have found a type of antibody in the South American pack animals—shared by their cousins, camels, as well as by sharks—that may give information on how to stop C. diff from colonizing the gut when it is able to do so. The llama antibodies aren’t suitable for human use directly, but they may provide a blueprint to develop a synthetic treatment.

From Mental Illness To Bacterial Infection

A few years ago, a new ally emerged in the battle against antibiotic-resistant bacteria. A drug called thioridazine used to be used to treat schizophrenia, but it has fallen out of favor for mental illness in recent years. Now scientists think they have a better understanding of why thioridazine works on conditions such as MRSA that do not respond to most antibiotic treatments. There are new indications that the medication is helping to break down cell walls in infectious bacteria even when those bacteria are resistant to ordinary antibiotics. That means that this medication can be used even for hardened strains of illnesses.

Thioridazine was introduced in 1978 for patients with schizophrenia. Though often effective for that condition—as well as insomnia and heroin withdrawal symptoms—there were some concerns about side effects. Many patients reported agitation and restlessness, in many cases leading them to stop taking the drug. Patients also reported drowsiness, dizziness, and vertigo, as well as mouth tremors. Moreover, long-term use was found to carry some risks of heart diseases and vision problems, since it was found that excess thioridazine is stored around the heart and behind the retinas of the eyes. Because of these and other concerns, thioridazine was largely dropped as a schizophrenia treatment by 2005.

The researchers who discovered the mechanism point out that thioridazine doesn’t kill the bacteria on its own; it makes the heretofore resistant bacteria once again vulnerable to antibiotics. It does this by removing the amino acid glycine from the bacterial cell walls. This weakens the walls, making it possible for antibiotics to get in and kill the cells even when resistance has developed.

The next step, according to members of the research team, is to determine what properties of thioridazine have this effect, and attempt to isolate them. That way, either antibiotics themselves can be redesigned to target glycine as well, or a medication can be developed that eliminates glycine, but without the other effects of thioridazine. The elements that make it an effective treatment for schizophrenia can also make it dangerous for people without the mental illness, and the side effects are also a concern. Researchers will be investigating ways to selectively eliminate the drug’s anti-psychotic properties.

Antibiotics from Pandas and Curry

Curry and pandas have a perhaps surprising link with human health. It involves a class of chemicals called cathelicidin-related antimicrobial peptides. These chemicals are common in mammals, having been isolated in humans, monkeys, mice, rats, rabbits, guinea pigs, pigs, cattle, sheep, goats and horses—and now, pandas. Cathelicidins play an important role in the immune system, helping it fight off unfamiliar infectious agents.

In fact, a cathelicidin may be partly responsible for the popularity of curry and similar foods. One important source of the substance is the spice turmeric, which has been used for centuries in Indian cooking and is in yellow mustard. Turmeric is rich in a type of cathelicidin called cucumin. In addition to its immune benefits, curcumin is a natural anti-inflammatory that research suggests may help fight prostate cancer.

In laboratory mice, curcumin stopped the spread of prostate cancer by inhibiting the inflammation that is frequently characteristic of the disease. Not only that, but curcumin produces no side effects and is safe for most patients, meaning anyone diagnosed with prostate cancer can be recommended curcumin, even if there’s not yet any indication that the cancer is starting to metastasize.

Another type of cathelicidin, AM, was isolated from the blood of the giant panda late last year. In panda blood, cathelicidin-AM fights infections, including fungal infections, helping protect the endangered animals from some of the most common illnesses. The natural antibiotic and immune component appears to be effective against a wide variety of bugs.

Fortunately, researchers have already figured out how to produce synthetic cathelicidin-AM in the lab, so they can leave the 1,600 pandas remaining. Demand may be high pretty soon—rese3archers say not only does cathelicidin-AM fight even drug-resistant bacteria, it does so in a way that doesn’t encourage the development of further resistance, making the compound a superweapon in the arms race between people and disease.

Out Of Control Microbe

Every healthy human being has what are called intestinal flora, microbes living in the gut that are of great importance in digestion and the immune response. These microorganisms are not a sign of disease; on the contrary, they are such an integral part of digestion that they are sometimes considered practically an organ in their own right, though the intestinal flora aren’t part of the body. However, when they get out of control, they can cause health problems just like any infectious agent.

For example, one of these microbes is Clostridium difficile. C. diff is normally present in the gut, but in limited numbers. However, when other gut bacteria are removed and C. diff is unchecked, it can cause serious illness. C. diff infection symptoms include watery diarrhea, fever, and nausea, and the infection can even lead to colitis.

In 2010, more than a third of a million people were hospitalized after developing a C. diff infection, and approximately another 150,000 were treated outside of hospitals. The condition is often spread in hospitals, where it is the most common cause of diarrhea. It leads to an estimated 30,000 deaths every year, directly or indirectly.

People are at risk for C. diff who are undergoing long-term antibiotic treatment, which can upset the balance of intestinal flora. Chemotherapy drugs and proton pump inhibitors (prescribed for chronic indigestion, GERD, and other conditions) can also make someone more prone to C. diff infection. In addition, people who have had one C. diff infection are more prone to another one.

The disease can be prevented with probiotics. Available as supplements or in some kinds of yogurt, probiotics help encourage the growth of the flora that help keep down C. diff. Administering probiotics to at-risk patients led to a 66 percent lower infection rate, according to a recent analysis of several studies.

If a patient does become infected, one available—though disgusting—treatments is called a fecal transplant. This is what it sounds like, unfortunately, though it is 90 percent successful. The idea is for the microbes from the donor help drive down the patient’s C. diff levels and fight back against the tide. A report last week suggested that this might soon be the standard treatment.

Resisting Antibiotic Resistance

When antibiotics were discovered about a century ago, they were looked at as a miracle. Horrific and deadly diseases suddenly became tractable and treatable. Unfortunately, this came at a price. As any antibiotic is more and more widely used, it’s only a matter of time before it becomes ineffective. Even with careful management, antibiotics lose their power through a process called antibiotic resistance.

When a bacterial infection is treated with antibiotics, it doesn’t kill off all the bacteria. A certain percentage survive, and they aren’t vulnerable to antibiotic. In more complex organisms, such protection from environmental hazards is passed on to offspring. This happens in bacteria, which reproduce by division, but there’s another, still faster way the resistance can spread. Bacteria actually pass genetic information around to peers, the way humans e-mail each other health tips from blogs.

Worse, it spreads geographically, meaning when an antibiotic loses its effectiveness, it becomes useless worldwide. Antibiotic resistance isn’t localized in one part of the world; it happens on a global scale. The effects are also felt globally. Antibiotic resistance could plunge the world back into the time before antibiotics helped bring a number of devastating illnesses under control.

One place where institutional change could make a huge difference is nursing homes. Patients in these facilities are frequently administered antibiotics as a preventative measure. In fact, as many as 70 percent of residents receive an antibiotic every year. Unfortunately, while well-intentioned, this is self-defeating, as the use of antibiotics in this way hastens resistance and makes the drugs less effective.

However, any time a patient, of any age, is given antibiotics they don’t really need, it contributes to antibiotic resistance. Antibiotics are not the only or necessarily the best treatment for all illnesses. If a doctor doesn’t want to prescribe antibiotics, it’s probably because other medications are about as effective.

Improving Antibiotic Effectiveness

Antibiotic resistance is a big problem in medicine. As a particular antibiotic is used more—and some are tossed around quite indiscriminately—the bacteria populations it is intended to kill gradually lose their vulnerability to the medication. Each time an antibiotic becomes ineffective, a useful weapon in the medical arsenal is lost.

Now a team of researchers in California is looking for ways to prevent bacteria from developing resistance to medications. We already know that bacteria build structures, called biofilms, that are communities of microbes which make it possible for the resistance of a handful of bacteria to be shared by the group.

The research team, based at the University of California, Berkeley, is looking for ways to attack these biofilms. This would slow down the process of antibiotic resistance and significantly extend the useful life of medications. What they’ve found so far is that bacteria create the structures immediately before expanding and growing into a full-blown infection.

The scientists looked at cholera bacteria to figure out the process by which this biofilm construction operates. This will provide valuable tools for destroying the structures and exposing individual bacteria to antibiotics and other forms of treatment.

“Now, we can come up with a logical approach to discovering how to take down their building, or prevent them from forming the building itself,” lead researcher Veysel Berk said in a release. “Eventually, we want to make these bugs homeless.”

These techniques may also be useful against other biofilms, such as dental plaques. The process could have widespread applications in areas outside medicine as well.

Other avenues of research include genetic manipulation of bacteria to prevent antibiotic resistance entirely. Bacteria pass on to their offspring the genes that allowed them to survive the initial antibiotic onslaught and eventually most of the bacteria are unaffected. What the team aims to do is find a way to deactivate or remove the genes that allow some bacteria to be safe from antibiotics, so as to prevent resistance from evolving.