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Everyone is concerned with the problem of antibiotics not working due to antibiotic resistance, that is, when bacteria resist the effects of antibiotics. Researchers typically study genetic changes that occur in bacteria over time, but researchers at Newcastle University in the UK found evidence for a another reason that antibiotics may not work in treating an infection. They found that bacteria can change shape and shed their cell walls, which are their outermost defense and the primary target of most antibiotics. Then when the antibiotics are stopped, they can go back to their original shape. Sneaky!

The researchers suggest that in the future we may have to treat infections with combined antibiotics, that is use antibiotics that kill bacteria with cell walls and also antibiotics that kill bacteria forms without cell walls (called L-forms).

Excerpts from  the study researcher Katarzyna Mickiewicz's post in The Conversation: Antibiotic resistance: researchers have directly proven that bacteria can change shape inside humans to avoid antibiotics   ...continue reading "Antibiotics May Not Work If Bacteria Change Their Shape"

A really interesting study found that in humans, taking antibiotics (which reduces the gut bacteria) may result in the flu vaccine not being as effective as in people who did not take antibiotics. An earlier similar study had found that this was true for mice, which is why the researchers did the study on humans.

The Stanford University and Emory University researchers studied healthy people who had recent (in last few years) flu vaccinations and those who hadn't had a flu vaccine for several years prior to the study. Some individuals took 5 days of broad spectrum antibiotics, and on day 4 received a flu vaccine, while others did not take antibiotics, but did receive the flu vaccine on day 4.

Not surprisingly: The antibiotics lowered the gut-bacterial population by 10,000-fold. While month by month there was increasing recovery, the resulting loss of overall diversity was detectable for up to one year after the antibiotics were taken. Keep in mind that they found that: "Notably, species richness and biodiversity were not fully recovered at 6 months, indicating long-lasting loss of unique bacterial species, consistent with previous studies." [BOTTOM LINE: Only take antibiotics when necessary.]

Interestingly, after antibiotic use, the researchers found other changes besides an alteration in gut bacteria populations. They also found changes within the immune system which resulted in an inflammatory state, which was due to "impairments in bile acid metabolism by the gut flora". In other words, taking antibiotics has a number of effects beyond treating an infection (the reason they were taken).

By the way, those who had taken flu vaccines in prior years had much better responses to the vaccines - they only had a minimal impact on vaccine response, even though they took antibiotics, than those who had not. Those who had not received flu vaccines or the flu in recent years had "low preexisting immunity", and taking the antibiotics (which resulted in loss of gut bacterial species) impaired their antibody response to the flu  vaccine. The researchers said: "The results of this study are consistent with the concept of immune responses in adults being largely determined by immune history and resilient to transient changes in the microbiome."

From Medical Xpress: Individual response to flu vaccine influenced by gut microbes   ...continue reading "Antibiotics, Flu Vaccines, and Gut Bacteria"

The issue of antibiotic resistance, that is, of antibiotics no longer working for bacterial infections in humans is a huge concern. So why are we squandering the antibiotic oxytetracycline on orange trees sickened with the disease citrus greening when a recent study by University of Florida researchers says it doesn't work?

The US Environmental Protection Agency gave permission for large-scale agricultural use of 2 antibiotics (streptomycin and oxytetracycline) to try to combat the bacterial infection that is destroying vast numbers of orange trees in Florida, Texas, and other states. However, the 2 antibiotics are also used to treat a number of bacterial infections in humans. And the latest development is that a study found that when oxytetracycline was sprayed on citrus trees for 6 months according to manufacturer's directions, it was no more effective than spraying water against the harmful bacteria (Candidatus Liberibacter asiaticus). 

Public health advocates, the FDA (Food and Drug Administration), and the CDC (Centers for Disease Control and Prevention) were all opposed to the EPA's antibiotic approvals for the citrus tree disease. They are very concerned that such large scale use could result in the development of antibiotic resistant bacteria, thus making these antibiotics useless in treating human illnesses. The CDC states that each year in the U.S., at least 2 million people get an antibiotic-resistant infection, and at least 23,000 people die.

Keep in mind that the European Union has banned the agricultural use of both oxytetracycline and streptomycin. Brazil has also banned these 2 antibiotics for agricultural use, and there citrus growers are battling the same citrus greening bacteria in citrus groves.

Steven Roach, a senior analyst for the advocacy group Keep Antibiotics Working has said:  “To allow such a massive increase of these drugs in agriculture is a recipe for disaster. It’s putting the needs of the citrus industry ahead of human health.”

From the NY Times: Spraying Antibiotics to Fight Citrus Scourge Doesn’t Help, Study Finds   ...continue reading "Time to Reassess Spraying Antibiotics On Orange Trees"

Many, many people wind up taking numerous courses of antibiotics at some points in life. Think of recurrent sinus infections or urinary tract infections or other infections. Or some conditions (e.g. dental or skin conditions) are treated with really long courses of antibiotics  New research (from 36,429 women participating in the long-running Nurses' Health Study)  found that women who take antibiotics over a long period of time during middle-age (40 to 59 years old), but even more so in late adulthood (60 years and over), are at increased risk of heart attack or stroke within the next 8 years.

How increased a risk for cardiovascular diseas? 28% or higher risk (compared to those who didn't take antibiotics)! But looking at the actual numbers it means: Among women who take antibiotics for two months or more in late adulthood, six women per 1,000 would develop a cardiovascular disease, compared to three per 1,000 among women who had not taken antibiotics.

Eight years was the length of the study, so it is unknown if the increased risk persists longer. The authors give a number of possible reasons for these results, but think it might be because antibiotic use results in gut microbial alterations. And the longer the antibiotic use, the more persistent the gut microbiome (microbial community) alterations. Other research studies supports this link (antibiotic use - gut microbe disruptions - increased cardiovascular disease). Another reason to eat in as healthy a manner as possible to feed beneficial gut microbes: a diet rich in fruits, vegetables, whole grains, seeds, and nuts.

From Medical Xpress: Antibiotic use linked to greater risk of heart attack and stroke in women

Women who take antibiotics over a long period of time are at increased risk of heart attack or stroke, according to research carried out in nearly 36,500 women. The study, published in the European Heart Journal today, found that women aged 60 or older who took antibiotics for two months or more had the greatest risk of cardiovascular disease, but long duration of antibiotic use was also associated with an increased risk if taken during middle age (aged 40-59). The researchers could find no increased risk from antibiotic use by younger adults aged between 20-39.  ...continue reading "Link Between Antibiotics, Heart Attacks, and Stroke Risk In Older Women"

Many people take probiotics in the belief that the probiotics will help their gut microbiome (microbial community) recover after taking antibiotics. This is because antibiotics kill both beneficial and pathogenic bacteria, and research shows it may take months for the gut to recover (it depends on the antibiotics taken). However, 2 studies (in both mice and healthy humans) conducted by a group of researchers at the Weizmann Institute of Science in Israel challenge that belief. The researchers used both mice and healthy humans in both well-done studies. They found that taking probiotics after a week of antibiotics actually delayed recovery of the gut microbial community in humans - months longer!

In summary: As expected, taking antibiotics had a big effect on the gut microbiome - the researchers wrote "a dramatic impact"  and "profound microbial depletion" (after taking one week of standard doses of "broad-spectrum antibiotics").  However, they found large differences among the 3 groups in gut microbial recovery after antibiotics. The spontaneous recovery group (they did not take probiotics after antibiotics) showed recovery of gut microbes within 3 weeks. The fecal transplant group (of their own fecal microbes which was collected before they took antibiotics) showed gut microbial recovery within 1 day of the fecal microbial transplant. In contrast, the group taking daily  probiotics for 28 days did not show full recovery (to where they were before antibiotics) by day 28, and the gut microbial community was still out of whack (dysbiosis) even 5 months after stopping probiotics (actually even at 180 days when the study ended).

What species were in the probiotics? Eleven species commonly found in ordinary probiotics: Lactobacillus acidophilus, L. casei, L. casei subsp. paracasei, L. planatrum, L. rhamnosus, Bifidobacterium longum, B. bifidum, B. breve, B. longum sbsp. infantism, Lactococcus lactis, and Streptococcus thermophilus.  These are all considered beneficial species. But keep in mind that the human gut has hundreds of microbial species - not just the few found in probiotics.

Bottom line: Eat well after taking a course of antibiotics so as to feed beneficial microbes, and do not routinely take probiotics thinking it will help the microbes in the gut.

What was also interesting was that in the first study where healthy individuals took the probiotics (and no antibiotics), they found that the probiotic species did not colonize the gut in everyone - only some species and in some people. It's as if there is a "resistance to colonization". This resistance is perhaps what other studies show - that within one week of discontinuing probiotics, they are gone from the gut.

From Science Daily - Human gut study questions probiotic health benefits  ...continue reading "Research Suggests Not Taking Probiotics After Antibiotics"

Many people struggle with recurring bacterial infections - taking antibiotics seems to suppress the bacterial infection (for example, in a urinary tract infection or UTI), but the infection soon comes back. And so the cycle continues - infection, then antibiotics, then infection, more antibiotics, and so on.

Thus it was with interest that I read about a recent study that found that some pathogenic bacteria grow slowly and enter a dormant-like state (hibernation) when exposed to antibiotics so the antibiotics don't affect them (they're "persisters"). This is because antibiotics typically target a bacterial cell's ability to grow (and so do not  have an effect on bacteria in a dormant phase). Then the bacteria resume normal growth and spread when the antibiotics are gone. This study was done in cell cultures in the lab using Escherichia coli bacteria from UTIs. Future research may look for drugs to target bacteria in the dormant state. From Science Daily:

Infectious bacteria hibernate to evade antibiotics

University of Copenhagen researchers have discovered a surprising tactic of pathogenic bacteria when being attacked by antibiotics: hibernation ...continue reading "Some Bacteria Evade Antibiotics By Going Into A Dormant-Like State"

A recent large study (using health data from the United Kingdom) found that children and adults who took five commonly prescribed types of antibiotics had an increased risk of developing kidney stones, compared to people who didn't take these antibiotics. The five types of antibiotics were sulfas, cephalosporins, fluoroquinolones, nitrofurantoin, and broad-spectrum penicillins. The antibiotics were taken orally (by mouth).

However, not all antibiotics were associated with an increased risk of kidney stones. The study examined 12 types of antibiotics, and found seven types that didn’t appear to influence the risk of kidney stones.The strongest risks for kidney stones were in children and adolescents, and with more recent exposure. The risk of kidney stones decreased over time, but remained elevated several years after antibiotic use.

The researchers pointed out that recent studies have found differences in the gut microbiome (community of microbes) between patients with kidney stones and those without kidney stones. And that studies find that the use of antibiotics disrupts the microbiome. (here and here) Another reason to only take antibiotics when absolutely necessary. From Science Daily:

Oral antibiotics may raise risk of kidney stones

Pediatric researchers have found that children and adults treated with some oral antibiotics have a significantly higher risk of developing kidney stones. This is the first time that these medicines have been linked to this condition. The strongest risks appeared at younger ages and among patients most recently exposed to antibiotics ...continue reading "Antibiotics and Kidney Stones"

The majority of women experience at least one urinary tract infection (UTI) at some point in their life. The normal treatment is antibiotics, but some researchers have questioned whether this is necessary - because some studies found most cases will simply resolve on their own without antibiotic treatment. Another issue is growing antibiotic resistance in treating UTIs - some women try one antibiotic after another in their UTI treatment due to antibiotic resistance.

Recently a study was conducted in 3 Scandinavian countries that looked specifically at this issue: Can uncomplicated UTIs be simply treated with non-prescription ibuprofen (e.g. Advil) or are antibiotics better? Women with UTIs were randomly assigned to a 3 day course of antibiotics (178 women) or a 3 day course of the pain reliever ibuprofen (181 women). They found that 53% of the ibuprofen group recovered without antibiotics (even though it took about 3 days longer than women who received antibiotics). However, seven cases (3.9%) of pyelonephritis occurred in the ibuprofen group, and none in the antibiotic group. Five of these patients were even hospitalized - but all recovered with antibiotics. Pyelonephritis is a kidney infection (the bacteria of the UTI has traveled to the kidneys).

There were no cases of pyelonephritis in the antibiotic group (they took  pivmecillinam). But even with an initial 3 day course of antibiotics - 11.2% of the antibiotic group needed a second course of antibiotics within 1 month to recover. The researchers main conclusions: since we can't tell who will respond well without antibiotics - therefore everyone should take them for a UTI.

My only question is: why not do this same study testing a course of D-mannose vs antibiotics for UTIs? One study found that non-prescription D-mannose to be as effective as antibiotics in treating recurring UTIs. Anecdotal evidence (from women) is that it works especially well for those caused by E. coli (up to 90% of UTIs). And antibiotic resistance will never happen taking it, because it's not an antibiotic. (Post on a mannose product for UTIs in development).  ...continue reading "Antibiotics Better Than Ibuprofen For UTI Treatment"

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Study after study, and such influential researchers as Dr. Martin Blaser (at New York University) have warned about antibiotics having a negative effect on the human microbiome - that they kill off gut microbes. And all conclude that therefore antibiotics should be used carefully - only when needed. But there are other reasons to be cautious about antibiotics as a recent article warned. Some people who take the class of antibiotics called fluoroquinolones develop a syndrome called fluoroquinolone-associated disability (FQAD) which causes crippling side-effects, including irreversible nerve damage. People who have fallen ill after taking fluoroquinolones call it being "floxed".

The FDA currently has "black box" warnings about fluoroquinolones - that they can cause tendon rupture or a risk of irreversible nerve damage in those taking the antibiotics. Black box warnings are placed inside a black box on drug labels and call attention to serious or life-threatening risks. Millions have taken these drugs, but some (the FDA considers it a rare event) develop the serious side-effects.

Many people (myself included) have taken fluoroquinolones, such as Levaquin, over the years for sinusitis treatment. Some have taken them multiple times. Most have not reported side-effects (including myself), but those who developed serious side-effects (floxed) are desperate for sinusitis treatments that don't involve taking antibiotics. Which is where alternative treatments using probiotics such as Lactobacillus sakei come in (yes, it works for sinusitis!). Excerpts from Nature (the international journal of science):

When Antibiotics Turn Toxic

In 2014, Miriam van Staveren went on holiday to the Canary Islands and caught an infection. Her ear and sinuses throbbed, so she went to see the resort doctor, who prescribed a six-day course of the popular antibiotic levofloxacin. Three weeks later, after she had returned home to Amsterdam, her Achilles tendons started to hurt, then her knees and shoulders. She developed shooting pains in her legs and feet, as well as fatigue and depression. “I got sicker and sicker,” she says. “I was in pain all day.” Previously an active tennis player and hiker, the 61-year-old physician could barely walk, and had to climb the stairs on all fours. Since then, she has seen a variety of medical specialists. Some dismissed her symptoms as psychosomatic. Others suggested diagnoses of fibromyalgia or chronic fatigue syndrome. Van Staveren is in no doubt, however. She’s convinced that the antibiotic poisoned her.

She’s not alone. Levofloxacin is one of a class of drugs called fluoroquinolones, some of the world’s most commonly prescribed antibiotics. In the United States in 2015, doctors doled out 32 million prescriptions for the drugs, making them the country’s fourth-most popular class of antibiotic. But for a small percentage of people, fluoroquinolones have developed a bad reputation. On websites and Facebook groups with names such as Floxie Hope and My Quin Story,thousands of people who have fallen ill after fluoroquinolone treatment gather to share experiences. Many of them describe a devastating and progressive condition, encompassing symptoms ranging from psychiatric and sensory disturbances to problems with muscles, tendons and nerves that continue after people have stopped taking the drugs. They call it being ‘floxed’.  ...continue reading "Some Antibiotics Can Have Crippling Side Effects"

The following is a nice article about a recently published study finding a link between some bacteria commonly found in the mouth and inflammatory bowel diseases (IBD). The researchers found that some strains of oral bacteria are also found in the gut of people with inflammatory bowel diseases.

They theorize that these bacteria make it down to the gut when saliva is swallowed - and for susceptible people this may trigger inflammatory disease. They did a number of experiments to determine that the antibiotic-resistant, inflammation causing species of Klebsiella pneumoniae and Klebsiella aeromobilis could be triggering IBD. These bacteria are able to replace normal colon microbes after antibiotic therapy.

However, it must be noted that other studies also find other microbial differences among those with IBD and healthy people - e.g. low or absent levels of Faecalibacterium prausnitzii, and even fungal and viral differences. From Harvard Magazine:

Gut Health May Begin in the Mouth

Chronic gastrointestinal problems may begin with what is in a patient’s mouth. In a study published Thursday in Science, an international team of researchers—including one from Harvard—reported on strains of oral bacteria that, when swallowed in the 1.5 liters of saliva that people ingest every day, can lodge in the gut and trigger inflammatory bowel conditions like Crohn’s disease and ulcerative colitis.

“For some time now, we’ve noticed that when we look at the microbiome of patients with inflammatory bowel disease, or IBD, we’ve found microbes there that normally reside in the oral cavity,” says study co-author Ramnik Xavier, chief of gastroenterology at Massachusetts General Hospital (MGH)....

Simultaneously, “There’s always been this other search, asking, ‘Are there pathobionts?’”—in other words, microbes that live innocuously in one part of the body but can turn pathogenic when moved to another. “For some time we have been looking for pathobiont organisms for Crohn’s and colitis.”

The researchers believe they have found them: two strains of Klebsiella bacteria, microbes commonly found in the mouth. ....the researchers pinpointed a strain of Klebsiella pneumoniae as the trigger for the immune response. A subsequent experiment using samples from two ulcerative colitis patients turned up another inflammation-causing strain, of Klebsiella aeromobilis

Checking databases of thousands of IBD patients at MGH and the Hospital of the University of Pennsylvania, Xavier and others found that people with inflammatory bowel conditions had significantly more Klebsiella bacteria in their gut microbiome than healthy patients did. Most likely, he explains, oral bacteria, including Klebsiella, traffics through everyone’s gut in the saliva we swallow. Usually it passes through harmlessly; but in people with a genetic susceptibility to IBD that alters the gut microbiome, the Klebsiella has a chance to take hold in the intestine and proliferate, inducing an immune response that causes the disease. 

And there is another twist: Klebsiella bacteria are often extremely resistant to multiple antibiotics. That explains, Xavier says, “why antibiotics have limited value in treating patients with Crohn’s disease and ulcerative colitis....  “Because we also showed in a 2014 paper that patients who took antibiotics—and this has been seen in the old clinical data accumulated before the microbiome was even examined in IBD—that patients who took antibiotics early in the disease had more complicated outcomes.” 

Klebsiella  pneumoniae Credit: Wikipedia