Abstract
Antimicrobial Resistance (AMR): Awareness to Solutions was the focus of the plenary session at the 60th AAVLD Annual Meeting. In October 2017, we learned about efforts to address this looming threat from a variety of entities: governmental, industrial, academic, and veterinary diagnostic laboratories (VDLs). It is critical that these groups continue to work together to share information on the current population and distribution of resistant organisms, and to work cooperatively toward reaching solutions and communicating recommendations. The VDL occupies a key position at the intersection of identification of resistant bacteria, recommendations regarding management, public health considerations, research (academic and industrial), surveillance, and education of veterinarians and the public. As the vision of the AAVLD is to be a world leader in advancing the discipline of veterinary diagnostic laboratory science to promote global animal health and One Health, the AAVLD is an integral part of the solution.
Defining the current state of the problem is foundational to future efforts in the war against AMR. In order to ascertain the population and distribution of resistant organisms, AAVLD laboratories are participating in 2 government-organized AMR projects that have collected over 3,000 unique clinical isolates and susceptibility data thus far during 2018. The Food and Drug Administration, Center for Veterinary Medicine, Veterinary-Laboratory Investigation and Response Network (Vet-LIRN) project has 21 participating AAVLD laboratories, and the USDA Animal and Plant Health Inspection Service, National Animal Health Laboratory Network (NAHLN) project includes 19, with some laboratories participating in both projects. Although the focus of each project is somewhat different, the common goal of surveying the susceptibility patterns of clinical isolates has been carefully considered such that the design of each project avoids duplication of bacterial isolates to allow future merging of these data. These projects would not be possible without the participation of VDLs.
Development of new laboratory tests and discovery of new therapeutic options require collaborative efforts of VDLs. Diagnosticians can best determine the practicality of a new test, and evaluate any purported benefits it offers. Clinical isolates, which are available in VDLs, are necessary for proper assessment of both test methods and therapeutics. It is critical for VDLs to collaborate with primary research entities, both academic and industrial, to move these efforts forward. With the discovery of new test methods and therapeutics, we must expand our testing options as appropriate to provide our clients with the most current and useful laboratory data.
In addition to generating new knowledge through surveillance programs and research, let us consider the direct impact we as diagnosticians have on our primary clients—veterinarians—who serve on the front line in the war against AMR. Practicing veterinarians make daily decisions to treat or not treat with antimicrobial drugs, which have implications for companion animal, food animal, and human health. VDLs guide veterinarians on appropriate sample collection, test selection, and interpretation and application of results. Veterinarians make management decisions based on the training they received in veterinary school, policies and best-practice guidelines, information from drug companies, and laboratory reports.
Laboratory reports containing culture and susceptibly results are key to evidence-based medicine; therefore, we must maximize the likelihood that veterinarians will use this information to make well-informed decisions regarding antimicrobial therapy. This can be accomplished by producing understandable reports and educating our clients.
To limit inappropriate use of antimicrobials, VDLs must consider the outcome when reporting routine test results. For example, should normal flora be identified and reported to clients? Should antimicrobial susceptibility testing be performed on normal flora? Should drugs be included on reports with the existence of a legality issue, a discrepancy between in vivo and in vitro results, intrinsic resistance, or a lack of interpretive guidelines? Some clinicians may presume that any information on the laboratory report is significant, and we cannot suppose that veterinarians know all the nuances of antimicrobial susceptibility testing (AST) interpretation. Although the final responsibility of drug choice rests on the prescribing veterinarian, we must recognize and be accountable for our influence as diagnosticians.
VDLs follow guidelines from the Clinical and Laboratory Standards Institute (CLSI) for AST procedures, but reporting may vary between laboratories. Should we report all drugs contained in every AST panel, or is it preferable to suppress antimicrobials of last resort such as vancomycin and imipenem, or employ a tiered approach to reporting? In 2018, the AAVLD Antimicrobial Susceptibility Testing Subcommittee teamed up with the Inter-laboratory Bacteriology Quality Assurance Survey (IBQAS) group to provide interpretive comments and recommendations for the compiled AST data. It is our responsibility as diagnosticians to run appropriate tests and communicate appropriate information so that veterinarians can make well-informed decisions regarding antimicrobial therapy.
Beyond our laboratory reports, VDLs have other opportunities to promote antimicrobial stewardship through client education. One example of an educational resource created for veterinarians on this topic is the Antimicrobial Use Guidelines for the Ohio State University (OSU)–Veterinary Medical Center (VMC), which is accessible to the public at https://go.osu.edu/osuvmc-abx-use. This online book provides guidance on appropriate selection of antimicrobial therapy based on expected pathogens by clinical presentation and was created by the OSU–College of Veterinary Medicine Antimicrobial Stewardship Working Group, which includes laboratory diagnosticians. Although it is tailored to drug use and availability at the OSU-VMC teaching hospital, it can serve as a model for stewardship programs at other institutions.
In my experience, few practicing veterinarians are aware of the procedure for arriving at a “susceptible” or “resistant” AST interpretation. Although knowing the details of how AST reports are generated isn’t necessary, it is important for practicing veterinarians to have a basic understanding of the procedures so they do not over-interpret the laboratory results. For example, based on consultations with veterinarians and senior DVM students,
The VDL is the nexus in the battle against AMR. Laboratories cooperate with disease outbreak investigations, collaborate with academic and industrial researchers, and educate veterinarians and the public. Diagnostic laboratories are the primary source of clinical isolates and antimicrobial susceptibility data for national AMR surveillance projects. We are a critical source of information and biological specimens required to move infectious disease research forward. All things considered, perhaps the most immediately impactful role of the VDL in the war against AMR is our day-to-day pathogen detection and susceptibility work to guide veterinary practitioners with correct and up-to-date data and recommendations.