What really works for infected eczema?
This article was first published in the March 2020 edition of National Eczema Society’s membership magazine, Exchange.
Consultant Dermatologist Susannah George and patient representative Anjna Rani share findings from the latest Cochrane research review on treatments used to reduce infection with the bacteria Staphylococcus Aureus in people with eczema.
Recent years have seen great progress in our understanding of the causes of eczema and the development of new treatments. In addition to the conventional treatments, such as emollients, topical steroids, calcineurin inhibitors and oral immunosuppressants, we now have new drugs such as dupilumab. However, one question that has remained difficult to answer surrounds the role of treatments designed to reduce bacteria on the skin in people with eczema.
Many people with eczema will be familiar with the weepy, crusty appearance of infected eczema. Most of the time this will be due to infection with bacteria called Staphylococcus Aureus (staph aureus). These bacteria live harmlessly on (or ‘colonise’) normal skin in many people and do not cause any problems. Yet, even if the skin of people with eczema is not obviously infected, we know that those with eczema are more likely to be colonised with the bacteria. This may be because the eczematous skin is damaged, which makes it easier for bacteria to live on.
Many treatments are routinely used to decrease staph aureus on the skin with the aim of preventing or clearing up an infection and preventing a flare-up of eczema.
These treatments include:
- topical antibiotics (those that are applied to the skin) like fusidic acid
- tablet antibiotics such as flucloxacillin
- antiseptic soaps
- bath additives such as ‘bleach baths’ (made up with diluted Milton baby sterilising solution).
However, although these measures have become a routine part of eczema treatment for many healthcare professionals and patients, our recent research suggests that treatments to reduce staph aureus on the skin may not be useful after all.
Our Cochrane systematic review, published in October 2019, aimed to understand the role of treatments designed to reduce staph aureus on the skin in people with eczema. An earlier version of the review, published in 2008, did not find any evidence that these treatments were useful. We looked at the results of randomised controlled trials (see right) and put the results of similar studies together in order to come up with the best answers we can.
We looked at different groups of treatments:
- tablet antibiotics
- topical treatments, such as antiseptic and antibiotic creams
- combination products, for example treatments including both a topical steroid and an antibiotic
- antibacterial bath additives
- clothes with antibacterial properties
A randomised controlled trial
This is where patients with the same condition are randomly divided into two (or more) groups and given different treatments. These studies often compare an active treatment with a dummy treatment or placebo. The patients are then followed up and assessed to see whether the treatment has helped their condition. Often the patients do not know which treatment they are being given and neither do the doctors or nurses assessing the improvement, which helps to make the results more accurate.
A systematic review
This summarises the results of available carefully designed healthcare studies and pools numerical data through a process called meta-analysis. Because it pulls together the findings of many different studies, it summarises the latest evidence about a condition and its treatment.
In the trials, the treatments were compared with placebos (an identical but inactive treatment), or with no treatment, or with the same preparation of cream or clothing but minus the ingredient that was designed to treat staph aureus.
Out of 41 studies, about half were conducted in Western Europe, but the rest came from all round the world. All the studies were conducted in hospitals, except for one, which was based in GP surgeries. There were 19 studies that included both children and adults, 12 with only children and four included only adults. The other studies didn’t say how old the patients were. Patients in some studies had very severe eczema and in others it was quite mild. Various different methods were used to decide how bad the eczema was.
We grouped studies of similar treatments together and tried to put the results together to answer the question as to whether a particular type of treatment was useful or not. Putting the results of the studies together was often dif cult because different measures were used to assess the response to treatment.
Combining steroids and antibiotics
The largest group of studies (14 in total) involved combinations of topical steroids and antibiotics and compared them to those using topical steroids alone. Two studies were in infected eczema, four were in uninfected eczema and the other eight did not specify. We found that these combination products may improve the eczema a little, but probably didn’t make much difference at all to quality of life compared to using only the topical steroid.
There were four studies that examined the role of oral antibiotics and compared them with placebo. Two studies were in patients with infected eczema, one in uninfected and one in patients who were colonised with staph aureus. When the results of these studies were put together, it was found that oral antibiotics were unlikely to make any difference in terms of improvement of the eczema or quality of life compared to placebo.
There were five studies that looked at bleach baths (two in uninfected eczema and three that did not specify whether the eczema was infected). Putting the results of these studies together found that bleach baths were unlikely to make any difference to the eczema or to patients’ quality of life.
The studies of antibacterial clothes were all so different that it was impossible to put the results together. However, they are unlikely to be any more helpful than untreated clothes.
We also looked at the numbers of patients who had experienced side-effects from the different treatments, but there were very few patients with side-effects, so it was difficult to draw any conclusions. Another concern is the potential for bacteria to become resistant to the antibiotics, which means that they may not work the next time they are needed. While we tried to look at the development of resistant bacteria, numbers were very small, so again it was difficult to draw any conclusions.
What does this mean for patients?
So what does this mean for patients? At the moment, there is no good evidence that antibiotics and other treatments designed to treat staph aureus infection in patients with eczema are helpful. Getting the eczema a bit better with topical steroids alone can decrease staph aureus on the skin.
The results of the review show that there is no point in taking antibiotics ‘just in case’ or where the eczema does not look infected. However, in patients with obvious signs of infection (for example, when the skin is weeping, oozing or yellow and crusty), or if the patient is unwell, then it is best to go with their doctor’s recommendation and take the antibiotics if the doctor thinks they should have them.
Despite the conclusions of this Cochrane review, this isn’t really the end of the story. Many of the randomised trials were very old and not conducted to the standards needed for clinical research today. Many of them didn’t go on for long enough to give a good idea of whether the treatment led to a long-term improvement. Many of them couldn’t be compared as they used different methods to assess the improvement of the eczema.
Researchers have recognised some of these problems with eczema research and over the last few years experts from all around the world have been meeting up to try to decide the best rating scales for measuring the severity of eczema for use in clinical trials. These meetings are part of the Harmonising Outcome Measures in Eczema initiative (‘HOME’).
With concerns about antibiotic resistance, new products that might be helpful in treating infected eczema are being tested in clinical trials. More high-quality clinical trials of existing and new treatments are needed to establish whether treating staph aureus in eczema is helpful. However, despite the findings of the review, the ultimate decision of whether antibiotics are needed or not for treating a patient’s eczema should remain with the doctor looking after them.