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Once again a study looked at biofilms in sinuses - but this time in the sinuses of healthy people and not those with sinusitis. Various different species of bacteria and small size "microcolonies" or biofilms were found in the healthy maxillary sinuses of all 30 people - so yes, it appears that the presence of biofilms in the sinuses is normal in healthy people. And yes, the presence of bacteria (even some low levels of species which are typically associated with sinusitis) are normally found in the sinuses of healthy people.  (Earlier research also found this last finding.)

The researchers state that it is normal for people to have "small size bacterial microcolonies" (of different kinds of bacteria) in the sinuses. The researchers theorized that the biofilms are probably "in equilibrium" under the influence of  "inhibiting defensive factors of the body", but they can become a source of infection if there are favorable conditions (such as illness). In other words, the researchers said that these biofilms are more like "bacteria films" in that they contain bacteria, but they live in small colonies that don't cause an inflammatory response with sinusitis symptoms.

One negative of this study was that advanced genetic sequencing was not done on the samples. Instead all samples taken from the people were cultured, which we now know misses a lot of bacterial and other microbial species (fungi, viruses). They looked at the microcolonies (biofilms) with scanning microscopes. Thus, while they found an assortment of bacteria on the sinuses of each person - they only found a total of 41 bacterial species among 30 persons. This is in contrast to studies using modern genetic sequencing that found hundreds of microbial species in healthy sinus microbiomes (microbial communities).

The other issue is that it is not clear to me if there were biofilms or  microcolonies that contained "beneficial" species in any of the samples. Other research suggests that biofilms of beneficial bacteria are also found in humans, and that this is one way beneficial bacteria that normally can't survive with exposure to oxygen can survive oxygen (the slime coating on the colony protects the bacteria within).

Other studies also stress that in healthy people there is "homeostasis" or "equilibrium" among all the microbes living in the sinuses, - a microbial community (which includes biofilms), and which helps maintain sinus health. See post with discussion of Mackenzie et al 2017 study: "A stable network of microbial interactions, established through processes such as niche competition, nutrient cycling, immune evasion, and biofilm formation help maintain homeostasis during health." But, as has been usual in recent sinus research, the current study also stated that much is unknown, that there are theories which are not yet proven one way or another, and more research needs to be done. Of course.... Excerpts from Morawska-Kochman et al research article in PLoS ONE:

The presence of bacterial microcolonies on the maxillary sinus ciliary epithelium in healthy young individuals

The aim of this cross-sectional in vitro study was to evaluate the mucosal surfaces of healthy maxillary sinuses, explore different forms of bacterial microorganism colonies present on the mucous membrane, and determine a mucosal surface area they occupy. Samples of the maxillary sinus mucosa were collected from 30 healthy patients (M = 11; F = 19). The material was obtained during the Le Fort I osteotomy performed during corrective jaw surgery. The morphological and morphometric analysis of sinus mucosa and bacterial film that was grown on it was performed using scanning electron microscopy (SEM) as well as imaging software.

Scanning electron microscopy analysis showed the presence of different bacterium and bacteria-like structures in all the analyzed samples. In most cases, the bacterial film was mostly composed of diplococci-like and streptococci-like structures on the mucosa of the paranasal sinus. In any case, the mucous layer did not cover the whole lining of the evaluated sample. Each colony consists of more than 20 single bacterial cells, which has grown in aggregates.

Under the conditions of normal homeostasis of the body, the maxillary sinuses present diverse bacterial colonization. The bacteria are dispersed or concentrated in single microcolonies of the biofilm on the border of the mucous covering the ciliary epithelium. There is no uniform layer of the biofilm covering the mucosa of the maxillary sinuses. Because the biofilm is detected on healthy individuals sinus mucosa, the clinical question if it may become pathogenic is unclear and require an explanation.

It should also be noted that pathogenic organisms, such as Pseudomonas aeruginosa, Haemophilus influenzae, Streptococcus pneumoniae, or Staphylococcus aureus can be found in patients without active symptoms of the disease. Usually, colonization is defined as the presence of bacteria on the mucous membrane, and the lack of the inflammatory response distinguishes it from an infection.

However, the bacteria film in contrast to typical biofilm might be defined by the presence of bacteria, that growth in colonies without inducing the inflammatory response. Thus, the aim of the study was to evaluate the mucosal surfaces of the healthy maxillary sinuses (without any history of recent acute sinus inflammations or chronic inflammation in the past), to identify different forms of bacterial microorganisms which could, under certain conditions, become opportunistic or pathogenic and determine a mucosal surface of the area they occupy.

Scanning electron microscope investigations revealed the presence of bacterial film on the surface of maxillary sinus mucosa in 30 patients. Moreover, microbiological examinations of specimens taken from study participants revealed the presence of various types of aerobic and anaerobic bacteria in 28 cases (93.34%) out of 30 studied samples. All samples had mixed flora. In total, 41 different microorganisms were isolated. The most frequently found microorganism was Streptococcus spp. in over 90% of all samples, while Propionibacterium acnes were present in 29,2% of samples, and Staphylococcus spp. was present in 17% of the samples.

Scanning electron microscopy analysis showed that the mucous layer has a thickness of 200 nm (± 40), which is covered up to 5% of the surface of each sample. The analysis showed the presence of bacteria-like microcolony structures in all analyzed samples.....Each colony consisted of more than 20 single bacterial cells, that had grown in aggregates. These clearly indicate the existence of a bacterial-like microcolony on maxillary sinus mucosa.

Bacterial microcolonies on the maxillary sinus ciliary epithelium in healthy young individuals. Credit: Morawska-Kochman et al.

An interesting study (published in September 2015) looked at how prevalent biofilms are in the sinuses of people with chronic sinusitis (with or without nasal polyps) as compared to healthy people (without chronic sinusitis). Biofilms are communities of bacteria sticking to one another and coated with a protective slime. The researchers found that the most biofilms were found in people with chronic sinusitis who also had nasal polyps (97.1%) , followed by those with chronic sinusitis without nasal polyps (81.5%), and the least in the control group of healthy patients (56%). They felt that the biofilms contributed to or had a role in chronic sinusitis. But note that the majority of people in all groups had biofilms.

Unfortunately nowhere in the study was there an analysis of the bacteria making up the biofilms. Are the bacteria in the biofilms different in the healthy people versus those with chronic sinusitis? The general assumption is that biofilms are formed from pathogenic (bad) bacteria such as Staphylococcus aureus, but it is known that beneficial bacteria such as Lactobaccillus plantarum and Lactobacillus reuteri can also form biofilms. One study concluded that: "L. reuteri biofilms secreted factors that confer specific health benefits such as immunomodulation and pathogen inhibition." So what was in the biofilms of healthy people (without chronic sinusitis)? Were the biofilms in healthy sinuses made up of protective beneficial bacteria or pathogenic bacteria that were kept in check by other "beneficial" microbes (which can be bacteria, fungi, viruses, etc) in the sinus microbiome?

Biofilms are very hard to eradicate, even with antibiotics. The researchers mentioned that "To date many different modalities have been tested, from Manuka honey to ultrasound and surfactant, but none have been shown to be very efficient." However, they did not mention other bacteria (probiotics) as a treatment possibilty in eradicating biofilms in the sinuses. There has been research looking at using probiotics against biofilms elsewhere in the body (such as dental plaque on teeth).

If biofilms from pathogenic bacteria are so pervasive in chronic sinusitis (81.5% to 97.1%), then it appears that some bacteria such as Lactobacillus sakei somehow predominate over them. I am saying this based on the majority of people writing to me saying that L. sakei treated their chronic sinusitis, as well as the experiences of my own 4 family members (at least 3, perhaps all 4 of us probably had biofilms in our sinuses based on the 81.5% to 97.1% numbers in this research). Something to contemplate. From the journal Acta Oto-Laryngologica:

Bacterial biofilms in chronic rhinosinusitis; distribution and prevalence.

Biofilms were more prevalent in patients with CRSwNP [chronic rhinosinusitis with nasal polyps] compared to both CRSsNP [chronic rhinosinusitis without nasal polyps] and controls [healthy people], and also on the ethmoid bulla compared to the middle turbinate, supporting a biofilm-related pathogenesis of CRSwNP....This study comprised 27 patients with CRSsNP, 34 patients with CRSwNP, and 25 controls.

Chronic rhinosinusitis (CRS) is today understood as a multifaceted group of diseases. The most established differentiation is between CRS with nasal polyps (CRSwNP) and without nasal polyps (CRSsNP)....Patients with CRSwNP have the worst quality-of-life scores, and they have frequent recurrences of their symptoms after surgery.

The pathophysiology of nasal polyps is poorly understood. Bacterial infection, in the form of biofilms, is proposed as a major drive behind the inflammation in CRS. Bacterial biofilms is identified as the agent behind an ever increasing number of chronic infectious diseases, ranging from endocarditis to dental caries. Bacterial biofilms are communities of bacteria in their sessile form, and can be extremely difficult to eradicate with conventional antibiotic therapy.

The total number of patients in the CRS group was 61, 23 females and 38 males, and median age was 40 years....Bacterial biofilms were detected in 97.1% of patients with CRSwNP, 81.5% of patients with CRSsNP, and 56% of controls. Patients with CRSwNP had highly significantly increased prevalence of biofilms compared to controls....The prevalence of biofilms in different anatomical locations within the nasal cavity differed....Biofilms were detected in 79.6% of the samples from the ethmoid bulla, 70.9% of the samples from the uncinated process, and 62.0% of the samples from the middle turbinate.

In this study a significantly increased prevalence of biofilms were found in patients with CRSwNP compared to controls, but also compared to CRSsNP. Indeed only one of the patients with CRSwNP was biofilm negative. This indicates a role for biofilms in the pathogenesis of CRS, but specifically in CRSwNP.

The pathophysiological mechanisms underlying nasal polyps are still poorly understood. Biofilms are shown to be heterogeneous and can be composed of both bacteria and fungi. Staphylococcus Aureus feature prominently in most biofilms found in the sinonasal cavity, being isolated in 50% of the samples. and can possibly facilitate co-colonization with fungi....Bacteria in a biofilm are shown to have up to a 1000-fold increased resistance to antibiotics compared to planktonic bacteria. These features of biofilms make them notoriously hard to eradicate.... In the setting of CRS we have the opportunity of direct local treatment which gives us a greater range of potential treatment options. To date many different modalities have been tested, from Manuka honey to ultrasound and surfactant, but none have been shown to be very efficient....In regards to nasal polyps, further studies are needed to investigate why some patients with biofilms develop nasal polyps while others do not.

Biofilms thrive in moist areas without too much turbulence, conditions found deep in the middle meatus. This may also explain why there were a higher number of biofilm positive CRSwNP patients, as regular nasal polyps originate in the ethmoid....In the opinion of the authors the findings in this article suggest a role for biofilms in CRSwNP.

Bacterial biofilm in a person with chronic sinusitis Credit: Thiago Freire Pinto Bezerra et al,  Braz. j. otorhinolaryngol. (Impr.) vol.75 no.6 São Paulo Nov./Dec. 2009

Some researchers are now testing to see if phage therapy  could be a possible treatment for some conditions, such as chronic sinusitis and wound infections. Phage therapy, which uses bacteriophages, was neglected for decades (except for Russia and the Republic of Georgia), but their use is again being studied as an alternative to antibiotics. A bacteriophage is a virus that lives within a bacterium, replicating itself, and eventually destroys the bacteria. The term is from "bacteria" and the Greek "phagein" which means to devour, so think of them as "bacteria eaters". Phages only attack specific types of bacteria (they are "bacterium specific"), so they’re unlikely to harm the normal microbiome (community of microbes) or any human cells.

I've been posting about the beneficial bacteria Lactobacillus sakei that treats chronic sinusitis, as well as some other probiotic (beneficial) bacteria that people have reported success with (see The One Probiotic That Treats Sinusitis). Most people contacting me or commenting have reported success with L. sakei products, but there is a group for whom L. sakei and other probiotics haven't helped. Why? And what can be done? Perhaps their sinuses are missing still unknown "keystone" species (very important microbial species for health). Or perhaps they have bacterial biofilms that even Lactobacillus species that are viewed as anti-biofilm cannot overcome. Perhaps phage therapy might help these people? 

Phage therapy is currently being tested by researchers in the treatment of chronic sinusitis in Australia. The video Antibiotic Resistance discusses phage therapy for sinusitis starting at 23:30. Looks promising.

And a write-up about the sinusitis phage therapy research from the Australian newspaper The Sydney Morning Herald: Medicine turns to bacteriophage therapy to beat superbugs

An arcane therapy for bacterial infections that dwelled behind the Iron Curtain for decades is making a comeback in Western medicine as a potential white knight against superbugs. Phage therapy involves infecting patients with viruses known as bacteriophages, which are the natural predators of bacteria, to kill the germs that antibiotics cannot.  ...continue reading "Phage Therapy May Help Sinusitis Sufferers"

Interesting, but in some ways horrifying - the hidden world of microbes teeming around us. With new techniques such as genetic sequencing we now know that at least a couple of thousand different species live in our water pipes in biofilms (concentrated microbial communities) that coat our water pipes. About eighty thousand bacteria per milliliter are in our drinking water, with one glass of clean drinking water containing ten million bacteria! And same as with microbes in human bodies, researchers think that a number of these bacteria and other microbes are beneficial and actually help purify the water. From Science Daily:

Our water pipes crawl with millions of bacteria

Researchers from Lund University in Sweden have discovered that our drinking water is to a large extent purified by millions of "good bacteria" found in water pipes and purification plants. So far, the knowledge about them has been practically non-existent, but this new research is about to change that.

A glass of clean drinking water actually contains ten million bacteria! But that is as it should be -- clean tap water always contains harmless bacteria. These bacteria and other microbes grow in the drinking water treatment plant and on the inside of our water pipes, which can be seen in the form of a thin, sticky coating -- a so-called biofilm. All surfaces from the raw water intake to the tap are covered in this biofilm.

Findings by researchers in Applied Microbiology and Water Resources Engineering show that the diversity of species of bacteria in water pipes is huge, and that bacteria may play a larger role than previously thought. Among other things, the researchers suspect that a large part of water purification takes place in the pipes and not only in water purification plants.

"A previously completely unknown ecosystem has revealed itself to us. Formerly, you could hardly see any bacteria at all and now, thanks to techniques such as massive DNA sequencing and flow cytometry, we suddenly see eighty thousand bacteria per millilitre in drinking water," says researcher Catherine Paul enthusiastically.

At least a couple of thousand different species live in the water pipes. According to the researchers there is a connection between the composition of bacteria and water quality."We suspect there are 'good' bacteria that help purify the water and keep it safe -- similar to what happens in our bodies. Our intestines are full of bacteria, and most the time when we are healthy, they help us digest our food and fight illness, says Catherine Paul.

Although the research was conducted in southern Sweden, bacteria and biofilms are found all over the world, in plumbing, taps and water pipes. This knowledge will be very useful for countries when updating and improving their water pipe systems."The hope is that we eventually may be able to control the composition and quality of water in the water supply to steer the growth of 'good' bacteria that can help purify the water even more efficiently than today," says Catherine Paul.

Even though this study was done in a laboratory, it gives further support for the treatment of sinusitis with bacteria and other microbes. And it could help explain why repeated courses of antibiotics don't "cure"  many chronic infections - because biofilms filled with pathogenic bacteria are signs of microbial communities out-of-whack. Which is why my family's successful chronic sinusitis treatment with kimchi (juice) containing Lactobacillus sakei is all the more impressive. From Science Daily:

Link between antibiotics, bacterial biofilms and chronic infections found

The link between antibiotics and bacterial biofilm formation leading to chronic lung, sinus and ear infections has been found, researchers report. The study results illustrate how bacterial biofilms can actually thrive, rather than decrease, when given low doses of antibiotics. Results of this study may lead to new approach for chronic ear infections in children.

This research addresses the long standing issues surrounding chronic ear infections and why some children experience repeated ear infections even after antibiotic treatment," said Paul Webster, PhD, lead author, senior staff scientist at USC and senior faculty at the Oak Crest Institute of Science. "Once the biofilm forms, it becomes stronger with each treatment of antibiotics."

During the study, non-typeable Haemophilus influenzae (NTHi) bacteria a common pathogen of humans was exposed to non-lethal doses of ampicillin, a class of antibiotics commonly used to treat respiratory, sinus and ear infections, or other beta-lactam antibiotics. The dose of the antibiotic was not enough to kill the bacteria which allowed the bacteria to react to the antibiotic by producing glycogen, a complex sugar often used by bacteria as a food source, to produce stronger biofilms when grown in the laboratory.

Biofilms are highly structured communities of microorganisms that attach to one another and to surfaces. The microorganisms group together and form a slimy, polysaccharide cover. This layer is highly protective for the organisms within it, and when new bacteria are produced they stay within the slimy layer. With the introduction of antibiotic-produced glycogen, the biofilms have an almost endless food source that can be used once antibiotic exposure has ended.

There are currently no approved treatments for biofilm-related infections. Therefore, bacteria forced into forming stronger biofilms will become more difficult to treat and will cause more severe chronic infections. Adults will suffer protracted lung infections as the bacteria hunker down into their protective slime, and children will have repeated ear infections. What may appear to be antibiotic resistance when an infection does not clear up may actually be biofilms at work.

Webster believes modern medicine needs to find ways of detecting and treating biofilm infections before the bacteria are able to form these protective structures. The difficulties of treating biofilm infections, which can be up to 1,000 times more resistant to antibiotics,have prompted some physicians to propose a gradual move away from traditional antibiotic treatments and toward non-antibiotic therapies.

The bacteria called Haemophilus influenzae are a common cause of upper respiratory tract infection. By attaching to surfaces in the body the bacteria form a biofilm. When the bacteria encounter non-lethal amounts of specific antibiotics they are stimulated to form a biofilm, a structure that causes chronic infection and which can be highly resistant to antibiotics. Credit: Paul Webster, Ph.D

Interesting to think of bacteria and biofilms (bacterial communities resistant to treatment) involved in stress related heart attacks. From Science Daily:

Bacteria help explain why stress, fear trigger heart attacks

Scientists believe they have an explanation for the axiom that stress, emotional shock, or overexertion may trigger heart attacks in vulnerable people. Hormones released during these events appear to cause bacterial biofilms on arterial walls to disperse, allowing plaque deposits to rupture into the bloodstream, according to research published in published in mBio®, the online open-access journal of the American Society for Microbiology.

"Our hypothesis fitted with the observation that heart attack and stroke often occur following an event where elevated levels of catecholamine hormones are released into the blood and tissues, such as occurs during sudden emotional shock or stress, sudden exertion or over-exertion" said David Davies of Binghamton University, Binghamton, New York, an author on the study.

Davies and his colleagues isolated and cultured different species of bacteria from diseased carotid arteries that had been removed from patients with atherosclerosis. Their results showed multiple bacterial species living as biofilms in the walls of every atherosclerotic (plaque-covered) carotid artery tested.

In normal conditions, biofilms are adherent microbial communities that are resistant to antibiotic treatment and clearance by the immune system. However, upon receiving a molecular signal, biofilms undergo dispersion, releasing enzymes to digest the scaffolding that maintains the bacteria within the biofilm. These enzymes have the potential to digest the nearby tissues that prevent the arterial plaque deposit from rupturing into the bloodstream. According to Davies, this could provide a scientific explanation for the long-held belief that heart attacks can be triggered by a stress, a sudden shock, or overexertion.

To test this theory they added norepinephrine, at a level that would be found in the body following stress or exertion, to biofilms formed on the inner walls of silicone tubing."At least one species of bacteria -- Pseudomonas aeruginosa -- commonly associated with carotid arteries in our studies, was able to undergo a biofilm dispersion response when exposed to norepinephrine, a hormone responsible for the fight-or-flight response in humans," said Davies. Because the biofilms are closely bound to arterial plaques, the dispersal of a biofilm could cause the sudden release of the surrounding arterial plaque, triggering a heart attack.

To their knowledge, this is the first direct observation of biofilm bacteria within a carotid arterial plaque deposit, says Davies. This research suggests that bacteria should be considered to be part of the overall pathology of atherosclerosis and management of bacteria within an arterial plaque lesion may be as important as managing cholesterol.

Note the red biofilm bacterial colonies within the diseased arterial wall:

Bacteria stained with a fluorescent bacterial DNA probe show up as red biofilm microcolonies within the green tissues of a diseased carotid arterial wall.

I spent time this past week searching the medical literature (US National Library of Medicine - Medline/PubMed) for the latest in sinusitis research. I wish I could tell you that amazing research has been happening recently, especially with the sinus microbiome (which could mean treating sinusitis with microbes), but I was disappointed. Really disappointed.

I did four searches: one for "sinusitis" (looked at 600+ studies dating back to summer 2013), then "chronic sinusitis" (going back to fall 2012), then "sinusitis, probiotics", and finally "sinusitis, microbiome". The "sinusitis, probiotics" search turned up 10 studies dating back to 2002. The "sinusitis, microbiome" search turned up a grand total of 13 studies, with the oldest dating back to 2004. Of course the sinus microbiome research by Abreu et al from September 2012  discussing Lactobacillus sakei and which I based my personal (and successful) kimchi sinusitis treatment was on the list (see my Dec. 5 post for a discussion of their research). But none of the other studies looked at Lactobacillus sakei (which is in kimchi).

Some of the findings among the many chronic sinusitis studies: microbial diversity is lower in antibiotic treated chronic sinusitis sufferers (than in healthy controls) and the microbial communities more uneven (meaning some microbes dominated over others), and greater Staphylococcus aureus populations among those with chronic sinusitis. After antibiotic treatment patients typically became colonized by microbes that are less susceptible to the prescribed antibiotics. One study found that Staphylococcus epidermidis (SE) may have some effectiveness against Staphylococcus aureus (SA) in the sinusitis microbiome in mice. Lactobacillus rhamnosus was not found to be effective against sinusitis. A number of studies reported biofilms in the sinuses which are highly resistant to medicines. Some studies found that smoking or exposure to second-hand smoke is linked to chronic sinusitis. (June 2016 UPDATE: I should have said that Lactobacillus rhamnosus (R0011 strain) was not effective against sinusitis when taken orally (a tablet) twice a day for 4 weeks in the study. There have been no further studies since then looking at L. rhamnosus for sinusitis treatment. It is unknown whether spraying or smearing/dabbing L. rhamnosus directly into the nostrils would have a positive effect)

Everyone agreed that state of the art genetic analyses found many more microbial species than older methods (the least effective was the traditional culture method). Several studies suggested that perhaps chronic sinusitis is due to immunological defects and one suggested that it was due to "immune hyperresponsiveness" to organisms in the sinuses. Surprisingly, some studies reported that there are more microbes or microbial species in chronic sinusitis patients than in control patients and that Staphylococcus aureus may be dominant (NOTE: These results may be due to not having been done with state of the art genetic analyses which would have picked up more microbial diversity. Another issue is where in the respiratory tract the samples were taken from, because it seems that the different areas have different microbial communities).

There was frequent mention that chronic sinusitis affects millions of people each year in the US, that little is known about its exact cause, and that there is controversy over appropriate treatment. Originally doctors thought that healthy sinuses were sterile, and it has taken a while to realize that is untrue. It is clear that researchers are only now trying to discover what microbial communities live in healthy individuals compared to those with chronic sinusitis.

But it appeared to me that the majority of the studies from the last 2 years indicated that treatment of chronic sinusitis is still: first try antibiotics, then antibiotics plus inhaled corticosteroids and perhaps nasal saline irrigation, then followed by endoscopic sinus surgery (or sometimes balloon dilation), then perhaps steroid drip implants (steroid-eluting sinus implants), and then there may be revision surgeries.

So I'm sticking with my easy-to-do, inexpensive, and fantastically successful kimchi (Lactobacillus sakei) sinusitis treatment. Of course! (see my Dec. 6, 2013 and Feb. 21, 2014 posts or click on the Sinusitis Treatment link for further information).

This study came out last month, but I think it is something to be concerned about any time you are thinking about getting cosmetic "fillers". Definitely check out the photo. From Science Daily:

Cosmetic treatment can open door to bacteria

Many people have 'fillers' injected into their facial tissue to give them 'bee-stung lips' or to smooth out their wrinkles. Unfortunately, a lot of cosmetic treatment customers experience unpleasant side effects in the form of tender subcutaneous lumps that are difficult to treat and which -- in isolated cases -- have led to lesions that simply will not heal. Research recently published by the University of Copenhagen now supports that, despite the highest levels of hygiene, this unwanted side effect is caused by bacterial infection.

Injections of fillers were previously reserved exclusively for trauma treatment -- when rebuilding a face disfigured in a traffic accident, for example. However, the jelly-like substances are increasingly being used in beauty treatments with the intention of making lips swell up and to erase the effects of ageing from the skin. Side effects in the form of stubborn, tender lumps or even lesions are becoming an increasing problem:

"Previously, most experts believed that the side effects were caused by an auto-immune or allergic reaction to the gel injected. Research involving tissue from patients and mouse models has now shown that the disfiguring lesions are actually due to bacteria injected in connection with the cosmetic procedure. What is more, we have demonstrated that the fillers themselves act as incubators for infection, and all it takes is as few as ten bacteria to create an ugly lesion and a tough film of bacterial material -- known as biofilm -- which is impossible to treat with antibiotics," says Morten Alhede, a postdoc at the Department of International Health, Immunology and Microbiology, University of Copenhagen.

Treatment with fillers is very common. According to the American Society for Aesthetic Plastic Surgery (ASAPS), treatment with products based on hyaluronic acid -- such as Restylane -- constitutes the second-most popular non-surgical cosmetic procedure in the United States. The precise figures for Denmark are not known, but there can be no doubt that the numbers are rising rapidly -- and a rise in the number of treatments will inevitably make the side effects more evident.

"Because a lot of cosmetic practitioners refuse to accept that side effects from filler procedures are caused by bacteria, claiming that such problems are caused by allergic reactions, the usual procedure has been to treat with steroids. This is actually the worst possible treatment because steroid injections exacerbate the condition and give the bacteria free rein. Fortunately, many of the filler producers have now become aware of the risk of bacteria and recognise that the gel can act as a bacterial incubator," says Associate Professor Thomas Bjarnsholt from the Department of International Health, Immunology and Microbiology. He continues:

"The problem will become very serious when the treatment becomes so widespread that people are able to walk in off the street to have their wrinkles smoothed out. Experts recommend keeping facial skin free from make-up for a month before undergoing a treatment involving fillers. Good hygiene is always important. Even when you abide by all the rules and regulations, it is difficult to avoid bacteria completely as they are often buried far below the surface of the skin."

Researchers estimate that between 1:100 and 1:1000 -- depending on the type of filler - develops an unfortunate bacterial infection which, in the worst-case scenario, may leave the person in question with a permanently disfigured face.

The biofilm that can develop in the wake of a filler treatment is resistant to antibiotics. "The good news is that infections can be prevented by prophylactic antibiotic treatment, i.e. injecting antibiotics together with the filler itself during the cosmetic treatment process. Our new research emphasises how important it is for all practitioners to follow this procedure to prevent the unwanted complications," explains Morten Alhede.

Injection of fillers: Side effects in the form of stubborn, tender lumps or even lesions are becoming an increasing problem. Photo credit: University of Copenhagen