Back to the Future: Penicillin-Susceptible Staphylococcus Aureus

All health professionals know and fear antibiotic resistance. A penicillin resistance has been present in Staphylococcus aureus for years due to its widespread usage for bacterial infections. However, penicillin may be making its come back! New data suggests that penicillin may becoming out of a period of antibiotic resistance. A study published by the American Journal of Medicine examined penicillin resistance in methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia.

At the McGill University Health Centre in Montreal, Canada, all adult MSSA bacteremia from April 2010 to April 2015 were reviewed for susceptibility to penicillin, erythromycin, clindamycin, and trimethoprim-sulfamethoxazole.  Out of 324 samples of MSSA bacteremia, 90 were susceptible to penicillin. This means that more than one quarter of patients with MSSA bacterium could use parenteral penicillin for treatment. This returning treatment may possibly have pharmacokinetic advantages over other beta-lactam, such as amoxicillin. Such pharmacokinetic advantages could potentially lead to better outcomes in the treatment of bacterial infections.

While working at a community pharmacy, I often fill prescriptions for amoxicillin, but I have never seen a prescription for penicillin. This new discovery regarding penicillin resistance could lead to a change in prescribing patterns from physicians in the future. I think that this discovery is also valuable at this time because other antibiotic resistances are emerging in our population. Bringing back an old antibiotic would be very useful to combat bacterial infections that are not responding to current top antibiotics. Although it is great to see the renaissance of an old antibiotic, antibiotic resistance is a serious problem and will continue to be a serious problem unless pharmacists step in to provide effective patient counseling and form beneficial interprofessional relationships with prescribers.

Am J Med. Published online February 25, 2016.

Link to article

Pharmacist-led feedback workshops increase appropriate prescribing of antimicrobials

Inappropriate antimicrobial prescribing is a common occurrence in hospitals, and may lead to increased patient morbidity. Not only does this produce deleterious effects for individual patients, but it also contributes to the growing global health problem of anti-microbial resistance. Research has indicated that most inappropriate antimicrobial prescriptions are written by junior doctors in their first 2 years of practice. Therefore, initiatives targeting these junior doctors and educating them on proper antimicrobial use may increase individual health outcomes and help alleviate the problem of antimicrobial resistance.

A European study aimed to reduce inappropriate antimicrobial prescriptions by targeting junior doctors with intervention provided by pharmacists. This was done via data collection on junior doctors’ prescribing habits, followed by feedback workshops aimed at addressing knowledge gaps, discussing social and behavioral aspects of prescribing, and encouraging reflection. 29 doctors were recruited for the study, 14 were randomized to the intervention group and 15 were randomized to the control group. The normalized rate of suboptimal prescribing was significantly lower for the intervention group than the control group. Analysis showed that pharmacist intervention increased junior doctors’ awareness of their prescribing behavior.

This article was a prime example of how pharmacist intervention in drug therapy can improve health outcomes, both on an individual and public health scale. Often, I feel doctors hesitate to consult pharmacists about drug therapy unless the drug being provided is a particularly complex or new drug (such as chemotherapy or psychiatric drugs). Something as commonplace as antimicrobials is not typically seen as being a serious enough drug to warrant pharmacist opinion. However, it is clear that by including pharmacists in the decision-making process on antimicrobial prescriptions and allowing them to educate prescribers, better health outcomes can be achieved. How do you think pharmacists can become more involved in the decision-making process and education for prescribing more commonplace medications, such as antibiotics, antivirals, etc.? Especially in an outpatient setting where pharmacists are often not on-site?

McLellan L, Dornan T, Newton P, et al. Pharmacist-led feedback workshops increase appropriate prescribing of antimicrobials. J Antimicrob Chemother. pii: dkv482. [published 2016 Feb 24]

Implementation of Penicillin Allergy Screening Tool to Optimize Aztreonam Use

In this article from the American Journal of Health System Pharmacy, researchers looked to determine whether pre-screening for a penicillin allergy could help to reduce the use of aztreonam.  Aztreonam is an antibiotic used to treat gram-negative infections.

The study looked at patients prior to and after intervention to account for inappropriate aztreonam use.  After intervention, the number of inappropriate doses decreased significantly.  And overall, the screening allowed for a cost avoidance of up to $100,000.  Use of B-lactam alternatives became more popular over the use of aztreonam.

This article is interesting because it shows that educating providers and doing pre-screening can help patients receive the appropriate medication and avoid adverse reactions.

Stacie ML, Brundige ML, Brown J, et al.  Implementation of a penicillin allergy screening tool to optimize aztreonam use.  Am. J. Health Syst. Pharm.  2016;73:298-306.

The use of Hospital Pharmacists on Antibiotic Choice on Inpatients

With the increase prevalence of antibiotic resistant infections, maintaining the integrity of older antibiotics while using more advanced antibiotics in certain situations has become an important aspect of hospital medicine. Programs such as the Antimicrobial Stewardship (AMS) have risen to help facilitate when these antibiotics should be used.  It is important for an interprofessional team to be assembled to make sure that antibiotics are being used properly.

There was a study conducted at two Australian hospitals to see how pharmacists believe that they can help in the role of managing antibiotic use as well as how they believe they are perceived in this role. The study interviewed 19 pharmacists of varying degrees expertise level as well as varying levels of education beyond the pharmacy degree.  The study also included 12 female and 9 male pharmacists.  The pharmacists were given surveys as well as were interviewed about questions pertaining to how they play a role in the use of antibiotics, how they are perceived in this role, and challenges they face in this role.

The results of these interviews showed that the pharmacist felt that they were experts when it comes to the use of antibiotics since they are specifically trained in medications. They also felt that they had a watchful responsibility over some of the specific antibiotics since they have to be specifically ordered from the pharmacy.  They felt that they were considered major problem solvers when it came to this issue or their profession in general.  They generally believed that they were not always used to the outmost importance by some of the other healthcare providers since they are traditionally seen as a dispenser.  They also are not the ones that ordered the medication therefore they are not seen in the same importance.  This is a major problem when it comes to  interprofessionalism between colleagues in the healthcare field.  Furthermore, by not using the pharmacist, the healthcare team is missing out on information from medication experts.

This study is one very specific example of how pharmacist are trained to make an impact on the prescribing that is going on in a hospital setting but yet how they are not being used to their fullest potential. Interprofessionalism is an important aspect in improving the care of patients. This study should be reproduced in different settings across the world to promote to use of pharmacist as well as increase the rapport between the different healthcare professionals on a healthcare team.

http://BMC Health Serv Res. 2015; 16: 43.

Effect of Behavioral Interventions on Inappropriate Antibiotic Prescribing Among Primary Care Practices

In this article, the scientists involved looked at the effects of behavioral interventions and rates of inappropriate antibiotic prescribing during ambulatory visits for acute respiratory tract infections.  The experiment had clinicians held responsible for their antibiotic prescriptions in 3 ways: they were either given electronic alternative suggestions, had to enter a rationale for prescribing into the patient chart, or had to report their prescribing numbers to a group of other clinicians.  The study found that two of the interventions had a statistically significant impact on the rates of antibiotic prescriptions. Having the clinicians enter rationale for their prescriptions and reporting their prescribing numbers to peers both reduced the number of inappropriate antibiotic prescribing for respiratory tract infection.

I think that this article is really interesting because we all know that there is a widespread problem with antibiotics.  We know that antibiotic resistance is becoming more and more of a serious threat. If there is a way that we may reduce the number of  antibiotic prescriptions that could have a significant impact on fighting/reducing resistance.


Meeker D, Linder JA, Fox CR, et al. Affect of behavioral interventions on inappropriate antibiotic prescribing among primary care practices. JAMA 2016; 315(6):562-570.

Effect of Behavioral Interventions on Inappropriate Antibiotic Prescribing Among Primary Care Practices

Improving Outpatient Antibiotic Prescribing

Over 250 millions antibiotic medications are prescribed each year and a large percentage of these prescriptions are unnecessary. Unneeded and extended antibiotic use can lead to adverse drug effects and antibacterial-resistant infections. There are regulatory agencies that require acute care hospitals to have stewardship programs to improve antibiotic use. Unfortunately, the majority of antibiotic use occurs in the outpatient setting where there are no steward programs.

A study over 18 months was completed to compare the effect of behavioral interventions that occurred after an antibiotic was prescribed for a respiratory tract infection. The interventions were suggested alternatives to antibiotic use, accountable justification for antibiotic treatment, and peer comparison by other providers. Inappropriate prescribing decreased from 22% to 6% with suggested alternatives, from 23% to 5% with accountable justification, and from 20% to 4% with peer comparison. The control group also had a decrease from 24% to 13%.

This study justifies further investigation to create interventions to decrease inappropriate antibiotic use. This includes specifying tactics toward each outpatient clinics and certain common antibiotics. A suggestion is to require clinicians to justify every prescription for antibiotics with indication documentation and comparison with peers.

This is very interesting. If all prescribers were required to justify their prescriptions, I believe that there would be less antibiotic use. Additionally, the prescribers could provide the pharmacists with test results if applicable, proving that an antibiotic is needed. This would greatly reduce antibiotic resistance and the related complications. Can you think of any cons to this solution?

JAMA. doi: 10.1001/jama.2016.0430. (accessed 11 Feb 2016).