Antibiotic Stewardship in Outpatient Care

Antibiotic-resistant pathogens require multiple strategies to decrease morbidity and mortality. According to the Centers for Disease Control and Prevention (CDC), antibiotic-resistant pathogens are implicated in at least 35,000 deaths and over 2.8 million infections every year in the United States (US)1. In 2019, 250 million oral antibiotic prescriptions were written in outpatient settings, roughly the equivalent of 8 antibiotic prescriptions for every 10 people. However, according to a Pew Charitable Trust study, 1 in 3 prescriptions written in these settings is considered unnecessary.^1-4

As part of the multidisciplinary healthcare team, infectious disease pharmacists are considered drug and pharmacotherapy experts and are now regarded as a vital part of the core clinical team, playing a key role in patient care and choice of medications prescribed.

The improper prescribing and excessive use of antibiotics has led to loss of the effectiveness of currently used antibiotics. Frequently, antibiotics prescribed for common acute infections are often prescribed for 10 days or more of therapy, which is generally longer than needed and puts patients at higher risk of adverse events such as Clostridioides difficile-associated diarrhea and drug toxicity and raises the chances for resistant strains to emerge.

At 129 Veteran’s Affairs medical centers, 40% of pneumonia infections were prescribed antibiotics for 8 days or longer, and in a single-center study, 42% of uncomplicated skin infections were prescribed antibiotic therapy for 10 days or longer.⁵ Depending on infection type, about 20-50% of antibiotic prescriptions for bacterial infections do not align with current guidelines or fail to consider local resistance patterns.^4,6,7,8

Antibiotic stewardship programs are designed to evaluate antibiotic use and introduce measures which improve how antibiotics are prescribed by clinicians, in addition patients are educated to use antibiotics for what they were prescribed for and to take the whole course. Not to stop when they feel better and save the rest of the pills. So if antibiotics are so widely mis-used, why aren’t these programs in place and implemented in all outpatient settings?

Although antibiotic stewardship programs in the hospital setting have shown remarkable value and healthcare benefit, community providers are facing several challenges and barriers that limit implementation. For example, prescribers come from diverse specialties, geographic locations, and practice types.

Also, for changes in antibiotic use to succeed, providers in outpatient settings need the resources and time to address inappropriate antibiotic prescribing. The CDC adapted their inpatient stewardship recommendations to the outpatient setting, noting that clinicians should do the following:⁹

•Demonstrate a commitment to optimizing antibiotic prescribing and patient safety

•Take one action for policy or practice to improve antibiotic prescribing

•Track prescribing practices

•Provide regular feedback to clinicians

•Provide educational resources and expertise on optimizing antibiotic prescribing

However, despite recent efforts by the Academy of Urgent Care Medicine, which developed an antibiotic stewardship education program, very few sites have completed the training to gain accreditation in antimicrobial stewardship.

According to a Pew Trust report, only about 50% of surveyed physicians are concerned about the problem of antibiotic resistance and inappropriate prescribing in their own practices, and they feel they prescribe antibiotics more appropriately than their peers.¹⁰ About 84% of physicians also report moderate pressure to prescribe antibiotics from their patients or their caregivers. Some providers even practice defensive antibiotic prescribing out of concern for missing bacterial infections and the possible medicolegal, patient satisfaction, and financial ramifications.

Although updated clinical practice guidelines have been released for two of the most common bacterial infections seen in the outpatient setting, community-acquired pneumonia (CAP) and skin and soft-tissue infection (SSTI), many prescribers are unaware of these updates, have the time to read them or have not received continuing education about updates from previous guidelines. There are many opportunities to make smart and informed choices when prescribing antibiotics, given the number of infections that occur annually for CAP (up to 5.6 million¹¹) and SSTI (~14.2 million¹²) in the US.

Antibiotic efficacy, safety, local resistance rates, and overall cost, as well as patient-specific factors and disease presentation should inform antibiotic stewardship in the community, or smart prescribing. A group of multidisciplinary experts convened in 2021 to discuss the topic of antimicrobial stewardship programs related to Gram-positive community-acquired infections. This group agreed that prescribers can help increase effectiveness of antibiotic stewardship by keeping in mind the “4 D’s” (1) prescribe an antibiotic only for a bacterial infectious disease, (2) choose an appropriate drug, (3) consider the dose, and (4) avoid excessive antibiotic duration.¹³

The following recommendations for the most common pathogens and patient populations in CAP and SSTI are for the “standard” patient with one of these bacterial infections; a good rule of thumb is that for 80% of cases, treatment should fall along these lines.

Smart prescribing recommendations for CAP:

Diagnosis
•In addition to key clinical observations, try to use diagnostic tests to reduce uncertainty

Duration of treatment
•Initial duration of antibiotic treatment should be 5 to 7 days, efficacy for this shorter period has been shown
•Short course associated with fewer adverse reactions and resistance development; Clostridioides difficile often occurs after certain types of antibiotics

Choice of drug
•Choose antibiotic based on local resistance patterns, known/suspected pathogen; national resistance rates are suitable alternative

•If local macrolide resistance rates are unknown, choose another first-line monotherapy
•If local rates are known to be less than 25%, consider a macrolide
•Informed by prior microbiological culture if available

•Common treatments to consider: beta-lactams + macrolides, tetracyclines, fluoroquinolones

Smart prescribing recommendation for SSTI:
Diagnosis
•Gather key history to help ascertain possible risk factors as culture results will not affect initial management
•It is important to exclude MRSA, or prescribe appropriately if unsure

Duration of treatment
•Evidence of SSTI
•Initial duration of antibiotic treatment should be 7 to 10 days
•Short course associated with fewer adverse reactions, such as Clostridioides difficile-associated diarrhea, and resistance development

Choice of treatment
•Incision and drainage are encouraged when clinically indicated, followed by culture
•May be sufficient to resolve superficial infection

•Choose antibiotic based on local resistance patterns known/suspected pathogen, national resistance rates ae suitable alternative
•Common treatments to consider: cephalosporins (except if methicillin-resistant S aureus is suspected), trimethoprim/sulfonamides, glycopeptides, oxazolidinones, tetracyclines

For further reading, please see the manuscript, supported by an expert Roundtable, “It’s about the patients: practical antibiotic stewardship in outpatient setting in the United States,” by Amin et al13, published in Frontiers in Medicine (https://www.frontiersin.org/articles/10.3389/fmed.2022.901980/full).

References

1. Centers for Disease Control and Prevention. Outpatient Antibiotic Prescriptions — United States, 2019. (2019). Available from: https://www.cdc.gov/antibiotic-use/pdfs/Annual-Report-2019-H.pdf (accessed September 14, 2021).
2. Blue Cross Blue Shield. Antibiotic Prescription Fill Rates Declining in the U.S. (2017). Available online at: https://www.bcbs.com/the-health-of-america/reports/antibiotic-prescription-rates-declining-in-the-US (accessed September 14, 2021).
3. Fischer MA, Mahesri M, Lii J, Linder JA. Non-visit-based and non-infection-related antibiotic use in the US: a cohort study of privately insured patients during 2016-2018. Open Forum Infect Dis. (2021) 8:ofab412.
4. Pew Charitable Trusts. Antibiotic Use in Outpatient Settings. (2016). Available from: https://www.pewtrusts.org/-/media/assets/2016/05/antibioticuseinoutpatientsettings.pdf (accessed December 14, 2021).
5. Lowery JLI, Alexander B, Nair R, Heintz BH, Livorsi DJ. Evaluation of antibiotic prescribing in emergency departments and urgent care centers across the veterans’ health administration. Infect Control Hosp Epidemiol. (2021) 42:694–701.
6. Hurley HJ, Knepper BC, Price CS, Mehler PS, Burman WJ, Jenkins TC. Avoidable antibiotic exposure for uncomplicated skin and soft tissue infections in the ambulatory care setting. Am J Med. (2013)126:1099–106.
7. Shivley NR, Buehrle DJ, Clancy CJ, Decker BK. Prevalence of inappropriate antibiotic prescribing in primary care clinics within a veterans affairs health care system. Antimicrob Agents Chemother. (2018) 62:e00337–18.
8. Jenkins TC, Knepper BC, Moore SJ, O’Leary ST, Caldwell B, Saveli CC, et al. Antibiotic prescribing practices in a multicenter cohort of patients hospitalized for acute bacterial skin and skin structure infection. Infect Control Hosp Epidemiol. (2014) 35:1241–50.
9. Sanchez GV, Fleming-Dutra KE, Roberts RM, Hicks LA. Core elements of outpatient antibiotic stewardship. MMWR Morb Mort Wkly Rep. (2016) 65:1–12.
10. Pew Charitable Trusts. Survey of doctors reveals challenges, strategies for reducing inappropriate antibiotic use. 2020. Available from: https://www.pewtrusts.org/en/research-and-analysis/articles/2020/08/06/survey-of-doctors-reveals-challenges-strategies-for-reducing-inappropriate-antibiotic-use (accessed September 14, 2021).
11. Magill SS, Edwards JR, Beldavs ZG et al. Emerging Infections Program Healthcare-Associated Infections and Antimicrobial Use Prevalence Survey Team. Prevalence of antimicrobial use in US acute care hospitals, May-September 2011. JAMA. 2014;312(14):1438-1446.
12. Hersh AL, Chambers HF, Maselli JH, Gonzales R. National trends in ambulatory visits and antibiotic prescribing for skin and soft-tissue infections. Arch Intern Med 2008; 168:1585–91.
13. Amin AN, Dellinger EP, Harnett G, Kraft BD, LaPlante KL, LoVecchio F, McKinnell JA, Tillotson G and Valentine S. It’s about the patients: Practical antibiotic stewardship in outpatient settings in the United States. Front Med. 2022;9:901980.