This report demonstrates that systematic educational interventions can improve the quality of antimicrobial susceptibility testing and reporting in clinical laboratories, bringing laboratory practice in line with established national standards, regardless of laboratory setting or size. The smaller community settings, however, have the most to gain from these interventions. These institutions tend to have fewer doctoral scientists as directors or even microbiologists or technologists with advanced training in microbiology and typically have more limited access to educational materials and training opportunities than larger laboratories. The motivating factors were broadly characterized as either national or local in scope, emphasizing the importance of “local champions” in implementing laboratory guidelines. Regional technical workshops, NLTN teleconferences, and CDC materials, including the CD-ROM on AST and the CDC AST MASTER website, were especially effective in improving AST testing and reporting. Hospital formularies, infectious-disease physicians, and pharmacists also influenced AST and reporting in local hospital laboratories.
The following motivation resources had limited effectiveness: (i) CLI newsletter and website, (ii) on-site consultation, and (iii) state guidelines for AST. Personnel who inspect clinical laboratories are typically generalists who have limited background in clinical microbiology. Thus, the technical assistance that they can provide is minimal. The state's guidelines for AST were taken from CLSI AST documents and were viewed as redundant by laboratories (14
Between 2001 and 2005, laboratory managers in smaller laboratories decided to discontinue on-site AST and increased the utilization of referral laboratories for AST. Some of the decisions to discontinue AST may have been due to efforts for cost containment, increased laboratory workload, or loss of trained personnel rather than due to educational motivators. However, the results indicate that laboratory managers went through a thoughtful decision process to determine the best option for AST.
The case studies are an effective strategy to evaluate technical competence, although it may be prudent to design additional cases to assess competence for different levels of laboratories, i.e., for laboratories of small hospitals that limit the scope of on-site AST versus the use of referral laboratories that perform testing that is more difficult. The expense of buying the updated CLSI documents every year is prohibitive for laboratories with limited resources. The CSLI AST recommendations are also very complex and detailed, requiring rigorous review by laboratory staff and ongoing educational interventions to maintain their technical competence (8
Variations in the choice of drugs used in antimicrobial testing panels for S. pneumoniae
may be explained by the fact that CLSI performance standards state that “selection of the most appropriate antimicrobial agents to test and report is a decision best made by each clinical laboratory in consultation with its infectious disease practitioners, pharmacy, the pharmacy and therapeutics, and the infection control committees of the medical staff” as well as the reporting of only first line drugs. Laboratories reported that local policy and medical resources such as the hospital formulary, infectious disease physicians, and pharmacists did influence their selection of antimicrobials to be tested as well as CLSI performance standards. Also, laboratories use predetermined antimicrobial panels marketed by manufacturers for disk diffusion and commercial MIC systems, and this influences the number of antimicrobial agents tested. Laboratories periodically change their panels when manufacturers inform them that new antimicrobials are available (19
). Each laboratory should decide which agents in the CLSI tables to report routinely (group A) and which must be reported only selectively (from group B). Results for group B agents not reported routinely should be available on request, or they may be reported for selected specimens (4
Managers and supervisors may not adopt accepted laboratory practice guidelines for a variety of reasons. These may include the perception that the changes are too expensive to implement, are unnecessary, or will not improve patient outcome. Although the factors that affect the adoption of guidelines have been well studied among clinicians (3
), much more work is needed to understand the important decision-making factors among clinical laboratories.
The results of this study suggest that state health departments and other public health agencies must promote appropriate AST testing using a variety of different media to ensure continuous quality improvement. Clinical laboratory improvement is a significant “core function” (6
) of state public health laboratories. As such, state public health laboratories have a major role and responsibility in establishing and communicating AST policies to laboratories. State public health laboratories must coordinate and promote quality assurance programs that help to ensure that all clinical laboratories are using appropriate methods for testing organisms of public health significance, that compare susceptibility testing results from clinical laboratories to those provided by reference laboratories, and that identify those antimicrobials that clinical laboratories are using for testing isolates of microorganisms of public health importance (8
). In summary, this report has shown that national and local motivation strategies were effective in improving AST practices among microbiology laboratories and suggests that these strategies should be more widely employed to bolster those improvements.