Antibiotics joined our growing arsenal of weapons in the fight against disease over seventy years ago. Their target – the bacterial infections that putrefied our wounds, filled our lungs with pneumonia, and made our genitals less than appealing to our lovers. Bacteria were worthy opponents, and with antibiotics, the war against infection seemed ours to win.
But gradually, two facts have become abundantly evident. The first is that not all bacteria are foe. There are billions of bacteria – many of them essential to our health – that call us home. We’re each colonised by trillions of microbes forming communities that occupy every imaginable niche in our body.
These microbial commensals – known collectively as our microbiome – have evolved with us over millennia, and a co-dependent relationship has resulted.
While we provide a cosy niche and abundant supply of food to the microbes living in our intestine or on our skin, they in turn help to release nutrients from otherwise indigestible dietary fibre, synthesise essential vitamins, or produce a moisturising film to keep our skin soft and supple.
The second fact is that antibiotics may be thwarting our best efforts to stave off infection by messing with the delicate ecosystems that our microbial companions form. By indiscriminately annihilating microbes with antibiotics, we are taking a carpet-bombing approach where an assassination is more what we’re after. Innocent bystanders, as well as some of our closest allies, inevitably end up as casualties.
Unsurprisingly, some wily species of bacteria have evolved to take advantage of an ecosystem that has been thrown out of balance. The diarrhoea-causing bacterium, Clostridium difficile, is one such organism that flourishes in the power vacuum that results after antibiotic treatment.
A small number of people naturally harbour C. difficile in their large intestine, but most become infected in hospitals or nursing homes, the typical breeding grounds for superbugs.
In recent years, a highly toxic strain of C. difficile has emerged in hospitals in North America. In 2010, it was estimated that half a million people in the US were infected with C. difficile, and up to 20,000 of those died from the infection. The C. difficile superbug is also on the move, with cases in Europe and Australia rising.
For an increasing number of people, even the strongest antibiotics are powerless against C. difficile. In these cases, exasperation has turned to ingenuity, with an increasing number of doctors abandoning chemical warfare in favour of an ecological approach to fighting C. difficile infection.
Introducing the poo transplant
The unsavoury, yet highly effective treatment that has been adopted as an alternative to antibiotics is the faecal microbiota transplant, aka the poo transplant. A poo transplant is exactly as it sounds – taking faeces from a healthy donor, and transferring it, usually via enema, to a willing recipient.
It’s a simple idea, really. By replacing a depleted, out-of-balance gut ecosystem with a robust and healthy one, balance is restored. C. difficile becomes out-competed by friendly bacteria and the diarrhoea ceases. Unlike blood infusions and tissue transplants, faecal transplants require no immunological typing (tests to determine donor-recipient compatibility) to prevent rejection.
Poo transplants are the ultimate in probiotics. Although consuming a tub of lactobacillus-laden yoghurt is easier to swallow than the idea of a faecal enema, the principals are essentially the same.
There has been a resurgence of the technique, faecal transplants are not new. A Denver surgeon, Dr Ben Eiseman, and his colleagues published the first report of the procedure in 1958. And once again, doctors are discovering what Eiseman did 50 years ago – that poo transplants work.
A recent review of all reported studies of faecal transplants to treat C. difficile infection found poo transplants to be effective in over 90% of cases. Recurrence of infection is rare and there has not been a single report of adverse side effects.
As simple as the procedure sounds, we don’t yet fully understand how faecal transplants work. This may be set to change, however, as global efforts to make sense of the staggering complexity of our microbiome ramp up. The Human Microbiome Project funded by the National Institutes of Health in the United States, and the European Commission-funded Metagenomics of the Human Intestinal Tract project, are beginning to define our most intimate microbial co-habitants.
As we grapple with the complexity of our microbial ecology, perhaps we will discover which specific microbes are responsible for reigning in C. difficile during a faecal transplant. It might be a single species, or perhaps it’s a combination of several.
By identifying the microbes responsible, the poo transplant could eventually be replaced with a probiotic pill containing only the necessary species required to right the system. The “yuck” factor would be removed.
Or perhaps there are particular foods and supplements that we could consume as prebiotics to favour the growth of healthy bacteria when superbugs take hold.
In the meantime, the simplest, and perhaps most obvious way of modifying our gut ecology when superbugs take hold may well be to transfer an ecosystem en masse, through the under-appreciated technique of the poo transplant.
This is the eighth article in Superbugs vs Antibiotics, a series examining the rise of antibiotic-resistant superbugs. Click on the links below to read the other instalments.
Part one: Washing our hands of responsibility for hospital infections
Part two: Superbugs, human ecology and the threat from within
Part three: We can beat superbugs with better stewardship of antibiotics
Part four: The hunt is on for superbugs in Australian animals
Part five: The last stand: the strongest of the superbugs and their antibiotic nemesis
Part six: Unblocking the pipeline for new antibiotics against superbugs
Part seven: A peek at a world with useless antibiotics and superbugs
Part nine: New antibiotics: what’s in the pipeline?
Comments on this article are now closed.
Trent Yarwood
Infectious Diseases Physician at Queensland Health and Associate Lecturer at University of Queensland
Everyone loves talking about faecal transplants for C. difficile.
I've not done one (or even seriously considered doing one) working in infection since 2008, and my consultants could only provide a single anecdote from the several years before I started.
The "yuk" factor means this gets column inches far out of proportion with its actual use in clinical practice. The hypervirulent strain of CD from overseas hasn't made significant inroads in Australia; Hopefully it remains that way in the future.
Adrian Tosello
Student
If faecal transplants prove to be effective in treating other gut related illnesses, e.g. crohn's and colitis (which both have trials in Australia for this procedure under way, I think?), I really hope the "yuk" factor doesn't get in the way of their use in this country. The prospect of being able to have one relatively safe procedure instead of years of immunosuppressors and steroids is quite tantalising.
Sue Ieraci
Public hospital clinician
Adrian Tosello - it might be worth reading up about the pathology of the chronic inflammatory bowel diseases (Ulcerative colitis and Crohn's Disease).
They are quite different conditions from the overgrowth of c difficile, which is known to be associated with antibiotic use. It can be specifically diagnosed on stool culture.
The issue is not so much the "yuk" factor as whether the appropriate disease is being treated with effective therapy.
Adrian Tosello
Student
Not sure about Crohn's, but there is research going on with faecal bacteria transplants and colitis. e.g. http://www.clinicaltrials.gov/ct2/show/NCT01545908 and http://www.clinicaltrials.gov/ct2/show/NCT01650038
Glad to read that the effectiveness of the treatment is more important than the public's perception of it, thanks!
Sue Ieraci
Public hospital clinician
Gut bacteria are "the new black" of the CAM industry.
It's important to distinguish the real issue of C. difficile infection from the "you need your gut bacteria re-balanced" approach.
While there is no harm likely from consuming yoghurt (except if there is too much added sugar), it's not a great idea for faecal transplant to become the coffee enema of the 21st century.
Tom Hennessy
Retired
Quote: it's not a great idea for faecal transplant to become the coffee enema of the 21st century
Answer: The theory is coffee binds up iron in the bowel. The iron theory , is going to be tested , in that they are about to target the iron in the bowel.
"We're now planning to develop treatments that reduce the amount of iron in the bowel and so could lower the risk of developing bowel
cancer. We hope to start using these in trials in the next few years in people who are at a greater risk."
Michael Bailes
logged in via Facebook
Sue not sure the CAM "industry" knows a lot about this
It is more the province of Professor Borody from Sydney University
http://www.the-scientist.com/?articles.view/articleNo/29352/title/Same-poop--different-gut/
Sue Ieraci
Public hospital clinician
Don't be so sure, Michael.
I'll see your Tom Borody and raise you a Huffington Post and a io9 comment:
"Fecal Transplant has been discussed in IBD (inflammatory bowel disease) forums for several years. I've read accounts from a few people who suffer from Crohns or Ulcerative Colitis trying it, in Australia I think, with very good results. I remember one DIY'er with colitis who tried it at home using her infant granddaughter's poo and as a result, she reported, her disease went into remission…
Read moreMichael Bailes
logged in via Facebook
Yes Sue, early days yet, but it still seems to me most of the hype is coming from mainstream medicine rather than CAM
Of course it is a journalist's dream topic
http://www.ploscompbiol.org/article/info%3Adoi%2F10.1371%2Fjournal.pcbi.1002779
Sue Ieraci
Public hospital clinician
Michael - you might be right about the "poo transplant" stuff, but the concept of "disordered gut flora" as the root of all evil is becoming well-entrenched in the alties' world.
A simple test: put "gut flora" into google and what do you get? Nothing about C difficile, but all the Mercolas, NaturalNews, purenewyou, naturalifestyle and paleodietlifestyles out there...
watch this space, I say...
Tom Hennessy
Retired
The majority of the world are lactose intolerant , don't have the bacteria to assimilate lactose , lack of lactobacillus bacteria , hence , eating yoghurts to get the lactobacillus. It has been shown the lactobacillus strain does not require the metal iron but other bacteria thrive in a high iron environment.
Read more"It is well known that pathogens increase growth rate by up to 8,000 times when exposed to increased levels of iron."
"An increase in iron levels, which happens during active IBD, inhibits…
Sue Ieraci
Public hospital clinician
No, Mr Hennessy - lactose intolerance is caused by the lack (generally congenital or developmental) of the (endogenous) lactase enzyme - the enzyme that breaks the sugar lactose into glucose and galactose.
Tom Hennessy
Retired
"yogurt and probiotics for their bacterial lactase activity"
You may think having lactobacillus in the gut , all the time , will NOT allow one to digest lactose , but , yoghurt and probiotics allow for the digestion of lactose because they contain lactase. Lactobacillus bacteria , WHEN they are overrun / overgrown by bacteria which do not produce lactase , can no longer digest lactose because there isn't enough lactobacillus in the gut , hence , supplementation with lactobacillus (a lactose digesting bacteria which contains lactase) in an attempt to recolonise the gut WITH a bacteria which DOES produce lactase TO digest lactose.
Sue Ieraci
Public hospital clinician
Here is more in simple language for Mr Hennessy:
"Lactose, or milk sugar, is digested by the enzyme lactase.
Lactase is produced in the small intestine. It catalyses (speeds up) the digestion of lactose into two smaller sugars, glucose and galactose.
The reaction involved is a hydrolysis reaction. This means that the lactose is broken down by reacting with a molecule of water. Lactose is a disaccharide, or 'double sugar', made by combining two monosaccharides (simple sugars), glucose and galactose…
Read moreTom Hennessy
Retired
Write this down and repeat it to yourself.
Lactobacillus (a lactose digesting bacteria which contains lactase)
Sue Ieraci
Public hospital clinician
Yes, Mr Hennessy, Lactobacillus contains some lactase. It just doesn't work well for humans with endogenous lactase deficiency.
Tom Hennessy
Retired
Coincidentally , babies are born with the ability to digest lactose but sometime in the short time after birth they lose this ability to digest lactose. One might surmise this acquired inability to digest lactose is DUE TO , the large amount of iron being fed to the children after birth. This high iron diet will allow the bacteria OTHER than lactobacillus to colonise the gut , "pathogenic overgrowth" , effectively disallowing the growth of ENOUGH of the lactobacillus to effectively digest the lactose.
"An increase in iron levels inhibits the growth of probiotic bacteria, including Lactobacillus."
Sue Ieraci
Public hospital clinician
Mr Hennessy not all children lose their ability to make Lactase - many adults can digest milk through their entire lives.
Lactase production is not about iron or bacterial overgrowth - it is about the endogenous production of lactase enzyme in the intestinal mucosa.
Comment removed by moderator.
Comment removed by moderator.
David Noel
Researcher
I have a popular article up about this topic, and the wider one of the rise in allergies, at:
Innerlandia -- The Unexplored Continent Within Your Body (Is Improved Public Hygiene Ruining Your Health?) -- <http://www.aoi.com.au/bcw/Innerlandia/>;