Report of the Korean Association of External Quality Assessment Service on Clinical Bacteriology and Mycology (2016)

Kim, Jae Seok; Lee, Hyoung Sun

Abstract

Annual proficiency surveys were conducted thrice in 2016 as a part of the Clinical Microbiology Program of the Korean Association of External Quality Assessment Service. This program covers the fields of clinical bacteriology and mycology. Additionally, another assessment involved three bacterial and two yeast trials. These sets were distributed to different laboratories for the Gram staining, culture, identification, and antimicrobial susceptibility tests of bacteria, as well as for culture and identification of yeasts. In 2016, the trials I, II, and III reported responses from 293, 292, and 285 laboratories, respectively, for bacterial assessment. For yeasts, 107 and 101 laboratories responded in trials I and II, respectively. A novel proficiency testing program was applied in 2016 with the "80%" rules for every laboratory. Identification of bacteria was acceptable for all isolates with the following order of accuracy: Klebsiella pneumoniae, 99.6%; Acinetobacter baumannii, 98.0%; Enterococcus faecalis, 97.6%; E. faecium, 97.5%; Morganella morganii, 97.2%; Streptococcus agalactiae, 94.4%; Staphylococcus saprophyticus, 93.9%; S. aureus, 93.2%; and Salmonella spp. group B, 90.6%. Species-level identification of Gram-positive cocci tended to be lower than that of the Gram-negative bacilli. Although genus level identification has been reported by a few institutions in case of Salmonella, there is a requirement for precise identification of its serotypes. In antimicrobial susceptibility testing, the results were generally similar, with the most accurate results attained for methicillin-resistant S. aureus and carbapenem-resistant A. baumannii. The microbiology laboratories using disk diffusion method for susceptibility testing should improve the lists of reportable antibiotics in their laboratories where cephalosporins have been reported to be efficient against Enterococci. Compared to previous years, the commonly isolated yeasts were successfully identified up to their species levels to a greater extent. Novel external proficiency systems have been applied for clinical microbiology laboratories since 2016, causing fewer cases of misleading external quality control reporting. These novel systems may contribute to the progress of the quality control systems. Laboratories should continuously improve the quality of their analyses with the help of these external quality assurance systems.