“Children should be allowed to play in the dirt because being too clean can impair the skin’s ability to heal itself,” The Daily Telegraph reported. It said scientists have found that common bacteria on the skin’s surface can “dampen down overactive immune responses, which can lead to rashes or cause cuts and bruises to become swollen and painful”.

This news report is based on research in human skin cells and mice. Researchers found that some non-harmful bacteria that live on the skin play an important role in regulating inflammation. These intriguing findings improve our understanding of the complex reactions that occur when cells are infected or injured.

While the newspaper suggests that the findings are directly relevant to children’s health, this was not investigated by the researchers, though they did suggest their results may have some application in the management of inflammatory skin disorders. At this early stage, however, this is speculation and much more research is needed.

Where did the story come from?

The study was carried out by Dr Yuping Lai and colleagues from the University of California and other academic institutions across the USA. The research was funded by the National Institutes of Health and was published in the peer-reviewed medical journal Nature Medicine.

The Daily Telegraph has given a good report of the research, although the focus on children’s health may lead readers to misinterpret the study’s methods. This was laboratory research and included some studies in live mice in which injury was induced.

The findings pave the way for future studies of these complex chemical responses in humans, particularly those with inflammatory skin disorders.

What kind of research was this?

This laboratory study was carried out in mice and human tissue. It investigated whether chemicals produced by the bacteria Staphylococcus epidermidis could inhibit skin inflammation.

In a normal immune response to infection or injury, there needs to be a balance between rapidly responding to the immune challenge (which involves some inflammation) and unnecessary inflammation. S. epidermidis is commonly present on the skin and in most people does not cause disease. In people with weakened immune systems, these bacteria can sometimes cause illness.

The researchers state that finding out how such bacteria exist on the skin without causing inflammatory responses could help them understand whether these bacteria have a role in immune responses in general.

What did the research involve?

The researchers treated human skin cells with a range of chemicals that are involved in the inflammatory response. They found that a chemical called poly(I:C) initiated the greatest inflammatory response. They then pre-treated some skin cells with a chemical produced by S. epidermidis to see whether it had any effect on the inflammation reactions that poly(I:C) induced.

Similar experiments were repeated in live mice, where patches on the ears were pre-treated with the bacterial by-product and then exposed to poly(I:C). The cells’ responses when exposed to other inflammation-inducing chemicals (lipopolysaccharide or phorbol 12-myristate 13-acetate) were also assessed.

The researchers then analysed whether other staphylococcal strains produced this bacterial by-product and if it had a similar effect on inflammatory processes.

The second set of experiments investigated how this bacterial by-product works. To study this, the researchers induced injury in mice that were genetically modified to be missing certain receptors in their cells (called toll-like receptors 3 or TLR3). These receptors are involved in initiating an immune response.

The researchers then assessed the effects of pre-treatment with S. epidermidis in these mice compared with the response in normal mice. Several other experiments explored in more depth TLR3 and inflammation, and how the substances produced by S. epidermidis can prevent this.

What were the basic results?

Pre-treatment of cells with the bacterial by-product (both in culture and in live mice) reduced the inflammatory response caused by poly(I:C). The researchers say this shows that “a product of S. epidermidis functions as a selected suppressor” of the inflammation induced by poly(I:C). It does this ultimately by inhibiting certain receptors called TLR3. They say a range of staphylococcal bacteria produce this by-product.

Pre-treating mice that were genetically modified to lack the TLR3 receptors with the chemical produced by S. epidermidis did not reduce inflammation, confirming that the TLR3 receptors are the target of the chemical. Other TLR receptors (TLR2) were also found to be important.

The chemical that suppressed inflammation in the skin cells was identified as Lipoteichoic acid (LTA), a major component in the cell wall of these types of bacteria. These LTAs had an opposite effect (i.e. they induced inflammatory responses) on other immune cells called macrophages, monocytes and mast cells.

How did the researchers interpret the results?

The researchers say that this study confirms the important role of TLR3 receptors in detecting injury to the skin and that LTAs produced by certain staphylococcal bacteria can inhibit the inflammatory response. They say that the skin is frequently exposed to the LTAs produced by bacteria and that S. epidermidis “may benefit the host by dampening unwanted inflammation”.

Conclusion

This laboratory study sheds light on some of the complex processes involved in the skin’s response to injury. Inflammation is an important response to immune challenges, such as infection and injury, but skin conditions such as psoriasis and eczema are associated with hyperinflammatory reactions (excessive inflammation).

This research suggests that bacteria such as S. epidermidis play an important role in regulating the inflammatory response. The researchers speculate that chemicals produced by this type of bacteria may moderate inflammation from injury and control inflammatory skin disorders. They also highlight the crucial point that any treatment that reduces the detrimental effects of inflammation would have to do so without increasing the risk of wound infection. This balance has yet to be established.

Despite the news reports, this study did not investigate how playing in the dirt might affect children’s immune systems. This interpretation is not surprising and there are theories suggesting that a lack of exposure to some germs early in life can adversely affect the immune system. However, this study was in the laboratory and it is too soon to say that the findings apply directly to children.

This is interesting research that will lead to further work in humans. Until the role of these chemicals has been studied further, the direct relevance to healthy adults or children or for treatment of people with inflammatory skin disorders is unclear.

Links To The Headlines

Children should be allowed to play in the dirt, new research suggests. The Daily Telegraph, November 23 2009
 

Links To Science

Lai Y, Di Nardo A, Nakatsuji T et al. Commensal bacteria regulate Toll-like receptor 3–dependent inflammation after skin injury. Nature Medicine November 22 2009 (advance online publication)

The quality of dementia care in hospitals has featured in many newspapers. The Times reported that campaigners have said, “Patients with dementia are staying too long in hospital and receiving ‘disgraceful’ care that worsens their condition.” The Daily Telegraph said that “one in three never go back to their own homes and are discharged to a nursing home instead.”

The news stories are based on a report from the Alzheimer’s Society, which surveyed a large number of carers, nursing staff and nurse/ward managers on the quality of care given to people with dementia. Although the report gives the current opinion of a broad cross section of these groups of people, it cannot be considered a consensus. The figures that have been quoted by the newspapers should also be considered as the collective opinion of those surveyed.

However, the people who were surveyed are among the most experienced in the care of people with Alzheimer’s, and their overwhelming opinion is that hospital care needs to be improved. The society has made several objectives to achieve this aim.
 

What is the basis for these news reports?

The news stories are based on a report called Counting the Cost, which was commissioned by the Alzheimer’s Society. The charity reports that there are 700,000 people with dementia in the UK and that their care varies considerably. This report is part of the charity’s 'Putting Care Right' campaign, which aims to improve the quality of care for people with dementia.

The Counting the Cost report surveyed 1,291 carers, 657 nursing staff and 479 nurse/ward managers from general wards in hospitals across England, Wales and Northern Ireland. All members of the Alzheimer’s Society (about 21,000 people) were also asked to participate. The ward manager/nurse survey was sent to all ward managers and nurse managers who were identified from two databases.

People who agreed to take part completed questionnaires on the quality of care given to people with dementia. The majority of respondents were from England (91% of carers, 89% of nursing staff and 86% of the nurse managers).

The report also used evidence from national reports, a systematic review of dementia care in hospital general wards, and other published research.

What did the report conclude?

The report is extensive and only a summary of its main findings are presented here:

• At any one time, a quarter of hospital beds are taken by people over the age of 65 with dementia, and 97% of nursing staff report that they always or sometimes care for a person with dementia.
• Across England, Wales and Northern Ireland, there is considerable variation in the quality of dementia care on general wards, with some being excellent and some demonstrating neglectful care.
• 86% of nurse managers said that people with dementia are hospitalised for longer periods than those admitted for similar medical conditions without dementia, and 49% of carers said that the duration of care was longer than expected.
• 47% of carers reported deterioration in the person’s physical health and 54% reported deterioration in dementia symptoms while they were in hospital.
• Over a third of people with dementia who were previously living in their own homes are discharged to a care home.
• 77% of nurse managers and nursing staff said that antipsychotic drugs were always or sometimes used to treat people with dementia in hospital. However, up to 25% of them thought that the drugs had not been appropriately prescribed.
• 77% of carers said they were dissatisfied with the overall quality of dementia care provided. Key areas of their dissatisfaction were:
  − Nurses not recognising or understanding dementia.
  − Lack of personal care.
  − Patients not being helped to eat and drink.
  − Lack of opportunity for social interaction.
  − Patients and carers not having as much involvement in decision-making as they would like.
  − The person with dementia not being treated with due dignity and respect.
• Nursing staff had concerns about:
  − Managing patients with challenging or difficult behaviour.
  − Communication difficulties.
  − Not having enough time to spend with patients and provide one-to-one care.
  − Problems with patients wandering around, and not being able to ensure patient safety.
• The report predicts that supporting people with dementia to leave hospital one week earlier than they currently do could result in savings of at least £80million a year.

Are these opinions widespread?

This report offers a broad cross section of the current opinion of carers and healthcare providers on the state of hospital care for patients with dementia. However, it cannot be considered a consensus as it is not clear exactly what proportion of those professional staff who were asked to participate did so, although the report says that the response level was high.

The report also notes that carers who responded to the questionnaire may have been more likely to have had a bad experience and, therefore, may not represent all carers’ views. Because of these factors, it is difficult to say exactly how representative these figures are of dementia care as a whole in England, Wales and Northern Ireland. Despite this, the report has identified key areas where improvements in care for people with dementia are needed.

Does this mean that hospital care for people with dementia is bad?

Although the survey looks at hospital care, it doesn’t take into account each individual’s situation. For example, various medical and social situations may influence decisions of whether to discharge a person from hospital to their own home or to another place of care. In many cases, it is not until a person with dementia is admitted to hospital that medical and social services become aware of their situation and recognise that they may need additional care. Admission to a care home should not always be assumed to be a bad thing. In some cases, it may lead to an improvement in the care of the person and give them opportunities for increased social interaction and a better quality of life.

In many cases, the medical reason for the person’s admission to hospital (e.g. infection or fall) and the unfamiliar environment may lead to some deterioration in both their physical and mental state. Although the carers’ survey identified many areas of dissatisfaction in the quality of nursing care provided, this should not be assumed to be intentional neglect by the healthcare professionals. Survey responses by nursing staff identify many of the challenges that they face in providing care. Recognition of these challenges provides an opportunity to address these issues.

What does the Alzheimer’s Society aim to do next?

The charity states that it aims to:

• Gain NHS recognition that dementia is a significant issue and that certain areas of care need to be improved.
• Reduce the number of people with dementia in the acute hospital setting.
• Get each hospital to identify a senior clinician to take the lead for quality improvement in dementia.
• Suggest the formation of specialist older people’s mental health teams to liaise with hospital management.
• Reduce the use of antipsychotics in people with dementia.
• Ensure that all patients are assisted in eating and drinking where necessary.
• Ensure that carers are informed and effective in the care of people with dementia.
• Involve people with dementia and their carers, family and friends in their care to improve personal care.
• Start to change the approach to care for people with dementia to one of dignity and respect.

Links To The Headlines

'Disgraceful' care leaves dementia patients in worse condition. The Times, November 17 2009

Hospital ‘makes dementia worse’. Daily Mail, November 17 2009

Half of Alzheimer’s patients come out of hospital 'worse than when they went in'. The Daily Telegraph, November 17 2009

Dementia gets worse in hospital. Daily Mirror, November 17 2009

Dementia patient care criticised. BBC News, November 17 2009

Links To Science

Counting the cost: caring for people with dementia on hostital wards. Alzheimers Society 2009