Quality control center keeps national antimicrobial resistance surveillance on solid footing

When the World Health Organization launched its Global Antimicrobial Resistance and Use Surveillance System (GLASS) in 2015, it created an international framework for standardized AMR surveillance. South Korea followed in 2016 with its own national system, Kor-GLASS, designed to generate high-quality, standardized AMR data compatible with GLASS. Now, a new study published in the British Journal of Biomedical Science has evaluated how well the quality assurance framework underpinning Kor-GLASS performed during a period of significant system expansion, offering a detailed technical account of how a centralized quality control center (QCC) sustained reliable surveillance data as new bacterial species and antimicrobial agents were incorporated.

Kor-GLASS operates through a three-tier network comprising collection centers, analysis centers, and a QCC. Clinical isolates identified at collection centers are forwarded to designated analysis centers according to predefined organism group-based specialization. Each analysis center performs standardized antimicrobial susceptibility testing (AST) for its assigned pathogen groups, while the QCC oversees network-wide data quality and harmonization. As of Phase III, the network includes 13 university hospitals nationwide, with five functioning as collection centers, seven as analysis centers, and one as the QCC. The system has progressed through Phase I (2017–2019), Phase II (2020–2022), and is currently in Phase III (2023–2025).

The QCC performs quality assurance through two principal mechanisms: interlaboratory proficiency testing (IPT) and external quality assessment (EQA). IPT evaluates the concordance of AST results between analysis centers and the QCC using a subset of collected isolates, whereas EQA assesses laboratory performance through the distribution of pre-characterized strains for species identification, AST, and AMR gene analysis. IPT was generally conducted on a monthly basis, with approximately 5% of isolates from each analysis center randomly selected during each round. EQA was conducted quarterly, with each round typically consisting of five strains. Acceptance criteria for IPT were defined as categorical agreement (CA) of at least 90% and major error rates below 3%, while EQA required an overall score of at least 90% to achieve pass status.

The study analyzed IPT and EQA outcomes generated by the QCC between 2020 and 2024, covering Phases II and III. During Phase II, a total of 180 IPT reports were generated based on 2,381 isolates, whereas 122 IPT reports were issued from 1,291 isolates during Phase III. Across all species tested, the overall categorical agreement consistently exceeded 97% throughout the study period. For Candida spp., CA, essential agreement, and total agreement rates during Phase II were 99.8%, 96.8%, and 98.3% respectively, with corresponding rates of 99.7%, 100%, and 99.9% during Phase III. The IPT pass rate was 100% during Phase II and 96.2% during Phase III, while the EQA pass rate remained at 100% throughout the study period.

During Phase II, a total of 26 major errors were identified, with reading-related errors and near-breakpoint discrepancies accounting for the majority of cases. These errors were primarily associated with difficulties in zone interpretation, disk placement, and narrow interpretive breakpoints. In contrast, the number of major errors decreased to just four cases during Phase III, all of which were attributable to data entry errors or sample-related issues. Notably, no reading-related errors were observed during Phase III following targeted educational interventions, indicating a substantial improvement in interpretive consistency. The authors emphasize that while a causal relationship was not formally established, the reduction in major errors attributable to interpretive issues was observed following systematic corrective actions and targeted educational interventions coordinated by the QCC.

Phase III brought two significant updates to the surveillance framework: the addition of ceftazidime-avibactam for Enterobacterales susceptibility testing and the inclusion of Haemophilus spp. as a new target bacterial species. Following the introduction of ceftazidime-avibactam, disk diffusion results were analyzed for a total of 870 Enterobacterales isolates. Complete categorical agreement was observed for 455 Escherichia coli isolates, whereas three discordant results (0.7%) were identified among 415 Klebsiella pneumoniae isolates. All discordant cases represented near-breakpoint discrepancies, in which zone diameters measured at the analysis center were 19–20 mm (interpreted as resistant), while corresponding measurements at the QCC ranged from 22 to 26 mm (interpreted as susceptible). Bland-Altman analysis demonstrated a small interlaboratory bias in zone diameter measurements between the two centers, with a mean difference of −0.81 mm.

For Haemophilus spp., an interlaboratory validation was conducted prior to formal implementation. AST results for validation isolates generated by the candidate analysis center were compared with results independently generated by two separate teams within the National Reference Laboratory and the QCC. Following three pilot rounds, a formal validation round was conducted in which all predefined acceptance criteria were met, confirming the suitability of expanding the analytical scope. The authors note that AST for Haemophilus spp. is technically challenging because it requires specific media and AST panels, and the emergence of β-lactamase-negative ampicillin-resistant Haemophilus influenzae has increased the complexity of routine testing in clinical laboratories.

Beyond routine IPT and EQA, the QCC undertook supplementary quality assurance activities to support sustained standardization, coordination, and capacity building within the Kor-GLASS network and the national One Health framework. These activities included regular communication with participating institutions, quality control support for laboratories participating in the Korean One Health project that perform AST of non-human-derived isolates, technical consultation, and educational support delivered through online practical lectures for laboratory technicians and quarterly operational meetings. Seven rare and epidemiologically significant strains, including multi-carbapenemase-producing Enterobacterales, were fully characterized and deposited as reference isolates in the National Culture Collection for Pathogens. All QCC activities were conducted under an ISO 9001:2015-certified quality management system.

The authors position their findings within a broader global context, noting that previous assessments of GLASS implementation in the WHO Eastern Mediterranean region revealed that while the system facilitated region-wide AMR data generation, further efforts are required to strengthen data quality and long-term system sustainability. Evidence from the South and South-East Asian region demonstrated that a structured international EQA network can systematically improve laboratory diagnostic performance and data reliability for GLASS-aligned AMR surveillance. In contrast to these studies, the present work focuses on the operational performance of quality assurance itself, demonstrating that a centralized, QCC-led framework with continuous IPT, EQA, and corrective actions can sustain high analytical performance during a phase transition involving system expansion.

Looking forward, the authors emphasize that quality assurance activities within the Kor-GLASS framework should be sustained and periodically refined in alignment with global updates and international guidance, including GLASS recommendations. The anticipated introduction of whole-genome sequencing into Kor-GLASS surveillance underscores the need to proactively establish genomic quality assurance frameworks, as international genomic surveillance networks have demonstrated that interlaboratory variation and data quality issues can substantially affect the reliability of WGS-based AMR surveillance. The authors conclude that centrally coordinated quality assurance represents not merely operational oversight but an evidence-based evaluation of how standardized laboratory data are generated and validated within a surveillance system, reinforcing its essential role in sustaining the credibility and future development of national AMR surveillance.

Subject of Research: Performance evaluation of a centralized quality control center supporting national antimicrobial resistance surveillance in South Korea

Article Title: Performance of a quality control center supporting national antimicrobial resistance surveillance

Article References: Shin, D. W., Kim, H., Park, J. S., Park, K. U., Choi, M. H., Kim, D., Jeong, S. H., Kim, H. J., Kim, Y. A., Ahn, K., Uh, Y., Kwon, Y. J., Shin, J. H., Kim, S. H., Shin, J. H., Kang, H. Y., Moon, D. C., Lee, S. Y., & Bae, S. (2026). Performance of a quality control center supporting national antimicrobial resistance surveillance. British Journal of Biomedical Science, 83, Article 16457. https://doi.org/10.3389/bjbs.2026.16457

Image Credits: AI Generated

DOI: 10.3389/bjbs.2026.16457

Keywords: Performance, quality, control, center, supporting, national, antimicrobial, resistance, surveillance, scientific research