From development to implementation? The 2016 IDSA Antibiotic Stewardship Guidelines – a personal assessment
By Benedikt Huttner
After nine years the Infectious Diseases Society of America (IDSA) has now published an update of its antibiotic stewardship (ABS) guidelines (in collaboration with SHEA).1,2 [You can find here the 2007 Guidelines and here the 2016 Update]. Since the last edition in 2007 ABS has been increasingly accepted as an important concept to control antimicrobial resistance and CDI, prevent antibiotic-related adverse events, “optimize resource utilization” and improve patient outcomes. Many countries now even mandate ABS programs in hospitals. This development may have motivated the change of the verb in the title of the guideline document, stressing “implementation” rather than pure “development” of ABS programmes.
Reading a guideline document is rarely very entertaining endeavor, probably since this type of document is usually intended for consultation with regard to a specific question at hand and not meant to be read from beginning to end. A clear outline can mitigate this problem. The 28 recommendations of the 2016 ABS guidelines are divided into subsections with the titles “Interventions”, “Optimization”, “Microbiology and Laboratory Diagnostics”, “Measurement” and “Special Populations” but within the sections they do not necessarily follow a logical sequence. ABS “objectives” such as limiting duration, promoting us of oral agents, PK/PD optimizations and reducing use of antibiotics with a high risk of CDI are mixed with methods to achieve these objectives (such as preauthorization, education, audit and feedback, computerized decision support and prescriber-led review). Personally, I feel that a guideline stressing “implementation” would have benefited from a clearer separation of ABS objectives and methods how to achieve them.
As to the content, overall, the guideline, does not hold many surprises. A comprehensive review of all recommendations is beyond the scope of this article. In the following, I will focus on a few issues that seem worth mentioning to me.
1. The concept of “de-escalation (or streamlining) of empirical antimicrobial therapy, a key recommendation of the 2007 guidelines, nearly disappeared from the 2016 update. The term “de-escalation” appears just three times in the entire document and is mentioned as a possible metric to evaluate ABS programs (“Proportion of patients with revision of antibiotics based on microbiology data”), but nowhere in a prominent position. This may have to do with the fact that “de-escalation” is a fuzzy concept with no universally accepted definition whose exact impact on patient outcomes and AMR remains largely unclear (studies suggesting a protective effective of de-escalation on mortality suffer from major “confounding by indication”).3 [See this recently published systematic review on de-escalation] While I personally do not regret the “fall from grace” of de-escalation, I would have welcomed a detailed discussion of the concept in the guidelines.
2. Some recommendations seem somewhat debatable. Are days of therapy (DOT) really superior to “Defined Daily Doses” to assess the impact of ABS interventions (weak recommendation, low-quality evidence)., or do they both suffer from serious shortcomings when used as aggregated measures? Do we really know which measure is more closely associated with outcomes such as CDI and antimicrobial resistance? Personally, I think that the advantages of DOT only emerge if the individual-level nature of the data is really leveraged, eg to assess duration of treatment etc., but this is not specifically addressed in the guidelines.
3. Also, the recommendation to use rapid viral testing for respiratory pathogens (weak; low-quality evidence) to reduce inappropriate antibiotic exposure seems somewhat problematic. Practicing in an institution where PCR for respiratory viruses is widely used, I have serious doubts whether this is a cost-effective intervention. Even a positive result for a virus rarely motivates prescribers to stop antibiotics. To be fair to the prescribers, a co-infection with a bacterial pathogen is often difficult if not impossible to exclude. We definitely need high-quality randomized trials to look into the impact of this intervention in adults.
4. PK/PD optimization has gained a prominent place in the guidelines with three recommendations addressing this issue. TDM of aminoglycosides and vancomycin is fairly standard in many hospitals, but the third recommendation “alternative dosing strategies for broad-spectrum β-lactams” (continuous and prolonged infusion) has just recently (re)gained interest, even though the evidence for a positive impact on patient outcomes remains weak. (Interestingly therapeutic drug monitoring for beta-lactams is not mentioned)
5. The guideline document mentions ABS in special settings, from neutropenic patients to neonatal ICUs. I was positively surprise that ABS for terminally ill patients, somewhat a “taboo” topic in the United States is now also addressed.
6. Two recommendations stand out for their negative formulation: The guidelines advise against relying only on education for ABS and against the use of antibiotic cycling strategies.
Finally, when first reading the guidelines, I was struck by the vagueness of some of the recommendations. Statements such as “We recommend intervention X compared with no such intervention”, “We suggest ASPs advocate for…” seem unusually fuzzy for a guideline document. This may be a consequence of the relatively poor evidence base on which ASP recommendations still stand (nicely reviewed in this recent paper in Lancet Infectious Diseases4). Out of 28 recommendations, 18 (64%) are classified as “weak” recommendations. In addition, 16 of 23 (70%) recommendations where the evidence was assessed, were based on low-quality evidence.
Overall, these guidelines are important and an update was urgently necessary.
They also show that there is still room to advance from “belief” to true “knowledge” on how we should implement ABS.
*Benedikt Huttner is an Infectious Diseases physician and practices at the Geneva University Hospital, Switzerland. He is member of ESGAP EC.
- Dellit TH, Owens RC, McGowan JE, Jr., et al. Infectious Diseases Society of America and the Society for Healthcare Epidemiology of America guidelines for developing an institutional program to enhance antimicrobial stewardship. Clin Infect Dis 2007;44:159-77.
- Barlam TF, Cosgrove SE, Abbo LM, et al. Implementing an Antibiotic Stewardship Program: Guidelines by the Infectious Diseases Society of America and the Society for Healthcare Epidemiology of America. Clin Infect Dis 2016.
- Tabah A, Cotta MO, Garnacho-Montero J, et al. A Systematic Review of the Definitions, Determinants, and Clinical Outcomes of Antimicrobial De-escalation in the Intensive Care Unit. Clin Infect Dis 2016;62:1009-17.
- Schuts EC, Hulscher ME, Mouton JW, et al. Current evidence on hospital antimicrobial stewardship objectives: a systematic review and meta-analysis. Lancet Infect Dis 2016.