Antimicrobial stewardship: what’s it all about?

The global problem of antibiotic resistance is threatening us. Since 2001, the proportion of methicillin-resistant Staphylococcus aureus (MRSA) infections in the community has doubled.

As one of the highest users of antibiotics in the developed world, Australia needs a more judicious approach to antibiotic use.

Antimicrobial stewardship programs, which aim to improve the appropriate use of antibiotics and reduce antibiotic resistance, have been shown to be effective in Australian hospitals.

Antimicrobial stewardship needs to be extended to the community where the greatest proportion of antibiotics are prescribed. Antibiotic restriction, education of prescribers and patients and prescribing feedback have already had some success.

Much of the advancement in modern medicine has been made possible through access to safe and effective antibiotics. Although they remain the mainstay of treatment for infectious diseases, antibiotics are not effective against most acute respiratory infections, which are usually caused by viruses.

The pipeline of new antibiotics has almost completely dried up and use of the antibiotics we have will inevitably lead to resistance. Antibiotic-resistant pathogens found in Australia include:

• methicillin-resistant Staphylococcus aureus (MRSA)
• multi-resistant Streptococcus pneumoniae
• vancomycin-resistant enterococci
• multi-resistant Escherichia coli and other enterobacteriaceae.

Patients who acquire an antibiotic-resistant infection stay in hospital longer and have higher morbidity and mortality.¹ The World Health Organization refers to antibiotic resistance as one of the greatest threats to human health. The world is facing a global disaster unless action is taken now to preserve antibiotic effectiveness into the future.

The factors leading to bacterial resistance are complex and multifactorial. Along with infection control and surveillance, antimicrobial stewardship aims to reduce inappropriate use of antibiotics and improve patient outcomes.

Australia is one of the highest users of antibiotics in the developed world, with around 22 million prescriptions written every year in primary care. The defined daily dose in Australia is nearly 23/1000 population/day compared with less than 15 for Denmark, the Netherlands and Sweden (Fig. 1).^2-5

In hospitals

The federally-funded National Antimicrobial Utilisation Surveillance Program monitors antibiotic use in hospitals. It provides reports every two months on inpatient use, which enables analysis of trends and comparison of usage between hospitals.

In the community

Estimating antibiotic use in the community is more difficult. It is based on a combination of Pharmaceutical Benefits Scheme and Repatriation Pharmaceutical Benefits Scheme reimbursement data, along with estimates of non-subsidised medicines obtained from surveying a representative sample of community pharmacies.

General practitioners prescribe the greatest proportion of antibiotics in Australia, mostly for acute respiratory tract infections. Antibiotics remain the most common class of medicine prescribed in general practice.

Resistant organisms are increasing in the community. These require treatment with antibiotics such as vancomycin, carbapenems and fluroquinolones, which are often used when all other antibiotics have failed. For example between 2001 and 2010, the incidence of MRSA in the community doubled from 10 to 20% of all reported S. aureus infections.⁶ In Tasmania, a recent increase inClostridium difficile – an infection closely correlated with antibiotic use – was observed.⁷ This was most likely linked to transmission and infection pathways in the community, not within hospitals, and was driven substantially by antibiotic use in the community.⁸

On a more positive note, when the selective pressure of antibiotics is removed, resistance can be reversed.⁹ In the 12 months following antibiotic cessation in individual patients in the community, resistance fades towards zero.¹⁰

Antimicrobial stewardship programs in hospitals have been shown to reduce inappropriate antibiotic use by 22–36%. Programs improve patient outcomes and reduce adverse consequences of antibiotic use, including antibiotic resistance, toxicity and unnecessary costs.¹¹

Since 2011, antimicrobial stewardship has been included in the Australian Commission on Safety and Quality in Health Care's National Safety and Quality Health Service Standards for hospitals and is one of the compulsory criteria of the hospital accreditation process. The majority of hospitals in Australia, including smaller regional facilities, have or are currently in the process of implementing stewardship programs. Guidelines for implementing antimicrobial stewardship in Australian hospitals have been published.¹²

Programs must be adequately resourced and supported by hospital management. In large hospitals, antimicrobial stewardship is generally driven by a multidisciplinary team led by a clinician (usually an infectious diseases physician or clinical microbiologist) and a pharmacist, ideally with specialised training in infectious diseases. Teams work collaboratively within the hospital to implement the program (Box 1).

Several measures are used to assess the success of programs including antibiotic use, expenditure and antibiotic resistance. One proposed outcome indicator is the incidence of C. difficile infection. ^8,12

An antimicrobial stewardship program was launched at the Royal Hobart Hospital in May 2009. The following activities were included in the program:

• formulation of guidelines
• the use of a computer-based antibiotic restriction and approval program
• regular infectious diseases ward rounds on the intensive care and oncology units
• daily stewardship ward rounds providing feedback to antibiotic prescribers.

In the first 12 months, spending on antibiotics was reduced by 30% (approximately $300 000), along with a 20% reduction in prescribing of broad-spectrum antibiotics such as ceftriaxone and meropenem.

Clearly antimicrobial stewardship needs to be extended to where the greatest use occurs.¹⁴ Three principal strategies are already in place in the community. These are antibiotic restriction, prescriber and patient education and post-prescribing feedback (Box 2).

These strategies have had some success. General practitioner antibiotic prescribing for acute respiratory tract infections significantly decreased between 2000 and 2005. However, since 2005 there has been little change (Fig. 2).¹⁶ This may be driven by consumer expectation – an NPS MedicineWise survey found that four in five Australians expected a prescription when they have an ear, nose, throat or chest infection.* Accordingly, in February 2012, NPS MedicineWise launched a five-year campaign against antibiotic resistance with a strong emphasis on community education.¹⁷

One approach could be to establish antimicrobial stewardship teams in the community. These could align with NPS MedicineWise to promote the quality use of antibiotics in the community. Teams could work out of Medicare Locals and residential aged-care facilities providing regular, ongoing NPS MedicineWise-endorsed education for prescribers and consumers, coordinated research, data collection and feedback (for example point prevalence surveys and clinical audits). In the future these teams might be guided by clinical standards for the quality use of antibiotics, set by the Australian Commission on Safety and Quality in Health Care's National Safety and Quality Health Service Standards for hospitals.

The teams could provide further focus on:

• delayed prescriptions – these are antibiotic prescriptions with instruction to the patient that they should only fill the antibiotic if they deteriorate.¹⁸ This effectively reduces antibiotic use without causing anxiety for the patient or doctor¹⁹
• hand hygiene to reduce the spread of respiratory and other pathogens²⁰
• alternatives to antibiotics – these include analgesics or decongestants for acute respiratory infections,²¹ topical treatments for the pain associated with otitis media,²² and corticosteroids ^23,24 all of which need more evaluation
• emphasis on the adverse effects of antibiotics (such as thrush, diarrhoea, nausea)
• improved communication with patients – the assumption that patients expect antibiotics is often incorrect, and a better shared understanding of the objectives of managing acute respiratory tract infections may well lead to fewer antibiotic prescriptions.²¹

Antimicrobial stewardship in hospitals reduces the inappropriate use and consequences of antibiotics and improves patient outcomes. Aspects of stewardship are already in place in the community. Many of these are led by NPS MedicineWise. Adopting novel stewardship strategies in the community could provide a systematic approach to the growing threat of antibiotic resistance.

*www.nps.org.au/media-centre/media-releases/repository/1-in-5-australians-expect-antibiotics-for-coughs-or-colds-new-nps-campaign

Duncan McKenzie is chair of the Tasmanian Branch of the Society of Hospital Pharmacists of Australia. He is also a member of the Therapeutic Guidelines Respiratory Infections Expert Group, and executive committee member of the Committee of Specialist Practice (COSP) for Infectious Diseases, Society of Hospital Pharmacists of Australia.

Matthew Rawlins is an executive committee member of the Committee of Specialist Practice for Infectious Diseases, Society of Hospital Pharmacists of Australia.

Chris Del Mar is a member of Therapeutic Guidelines Writing Committees, coordinating editor of the Cochrane Acute Respiratory Infections Group, a member of the Remote Primary Health Care Manuals editorial committee, and supported by NHMRC grant GNT1044904.

Cairns KA, Jenney AWJ, Abbott IJ, Skinner MJ, Doyle JS, Dooley M, et al. Prescribing trends before and after implementation of an antimicrobial stewardship program. Med J Aust 2013;198:262-6.