Antimicrobial stewardship programs (ASPs) aid physicians in providing optimal antimicrobial therapy to their patients, prescribing the right antimicrobial regimen to the right patient for the right period of time—and avoiding unnecessary antimicrobial use, writes Vera P. Luther, MD, in the August issue of CLN.

Ultimately, ASPs aim to improve patient outcomes while limiting adverse drug events and antimicrobial resistance. ASPs also have been shown to save resources and money. ASPs and prescribing physicians depend on information and guidance from the clinical microbiology laboratory in order to accomplish these goals, making the laboratory vital to patient care and the success of ASPs, according to Luther, an associate professor in the Department of Internal Medicine, Section on Infectious Diseases at the Wake Forest School of Medicine in Winston-Salem, North Carolina.

Her article outlines three key roles labs have in promoting antimicrobial stewardship:

Antibiogram Reporting

Clinical microbiology laboratories conduct surveillance on local antimicrobial resistance trends among microbial pathogens. The collection, organization, and communication of resistance data culminates in the creation of an antibiogram. Antibiograms provide critical information to ASPs and prescribing physicians on institutional susceptibility patterns.

Most laboratories provide institution-wide antibiograms that report on the susceptibility of clinically relevant microbial pathogens to various antibiotics over a defined period of time. Some laboratories also prepare more specific antibiograms.

Given the important function that these antibiograms have in

patient care, their quality is essential. Laboratories can ensure useful and accurate antibiograms by adhering to the guidelines for cumulative susceptibility reporting from the Clinical and Laboratory Standards Institute (CLSI).

Patient-Specific Information

Laboratories provide patient-specific information by identifying microbial pathogens and performing antimicrobial

susceptibility testing. This information is necessary so that empiric antimicrobial therapy can be narrowed appropriately.

The time it takes a laboratory to report this information directly impacts the duration of empiric antimicrobial therapy, the time to directed therapy, or discontinuation of unnecessary therapy.

Specimen and Reporting Quality

Laboratory guidelines, policies, and procedures that ensure high-quality specimen processing have an important role in limiting unnecessary antimicrobial use. Clinical microbiology laboratories can work directly with ASPs to jointly create

guidelines, ensuring optimal results communication to physicians.

Luther’s article discusses how rapid diagnostics, in combination with ASP interventions, can improve patient care by decreasing overall antimicrobial use, the time to directed or optimal antimicrobial therapy, and the length of hospital stays, while also decreasing overall healthcare costs.

During the past decade, there have been several advances in rapid diagnostic testing. Examples of these techniques include matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH) technology, quantitative polymerase chain reaction (qPCR) assays, and multiplexnucleic acid assays. Compared with standard techniques that require 48–72 hours for final results, these methods can greatly reduce the time to pathogen identification by providing final organism identification within hours of growth.

Luther also describes how effective communication between the clinical microbiology laboratory and prescribing physicians can optimize antimicrobial regimens and deliver safe patient care. This communication may take several forms, including verbal and written test results reporting. It is imperative that reporting be timely, clear, understandable, and accessible to prescribing physicians.

Laboratories should have procedures in place to ensure effective communication, and these procedures should be reviewed and updated regularly.

Pick up the August CLN to learn more about the role of clinical microbiological labs in antimicrobial stewardship.