8th EQAsia External Quality Assessment trial: Escherichia coli, Klebsiella pneumoniae, Acinetobacter spp. and Staphylococcus aureus 2024

This report summarizes the results of the 8th External Quality Assessment (EQA) trial of EQAsia, a Fleming Fund Regional Grant. It aims to strengthen the provision of External Quality Assessment (EQA) services across the One Health sector among National Reference Laboratories / Centres of Excellence in South and Southeast Asia. The EQAsia project has entered a second phase (2023 to 2025) in which it continues to deliver the established EQA programme focussing on both Human Health (HH) sector and Food and Animal Health (AH) sector laboratories across the region.

The period of the trial was April – June 2024 and consisted of bacterial identification and antimicrobial susceptibility testing (AST) of four prominent WHO and FAO priority pathogens, namely: Escherichia coli, Klebsiella pneumoniae, Acinetobacter spp. and Staphylococcus aureus.

A total of 20 HH and 18 AH laboratories participated in this EQA trial. Four AH laboratories did not submit any results. Similarly to the previous EQAsia EQAs, participating laboratories could choose one or more panels among the ones offered in the current EQA round. In total, data were submitted by 32 laboratories for the E. coli panel, 25 laboratories for the K. pneumoniae panel, 21 – for Acinetobacter spp., and 33 – for S. aureus. The participating laboratories were from 14 countries situated in South and Southeast Asia (Bangladesh, Bhutan, Brunei Darussalam, Indonesia, Laos People Democratic Republic, Malaysia, the Maldives, Nepal, Pakistan, Papua New Guinea, Philippines, Sri Lanka, Timor-Leste, and Vietnam).

The bacterial identification component consisted of identification of the five strains of the organism in question (target organism) among a total of seven strains. Half of the laboratories that submitted data for the E. coli panel (n=16) identified all isolates in this panel correctly. While in the other three panels, there were only a few laboratories that had difficulties in determining the correct bacterial identification of the target isolates.

Overall, laboratories had a very good performance score throughout all four panels. The success rate in the S. aureus and E. coli panel was the highest (95.6% and 94.8% average score, respectively), followed by K. pneumoniae – 91.4% and Acinetobacter spp. – 90.0%.

Laboratories were ranked based on their average score across the panels in which they participated. The average score varied between 69.6% (rank #34) and 98.9% (rank #1). The total average score among all 31 laboratories that submitted results was 92.9%, while the median was 95.3%.

As with previous EQAsia EQAs, many of the laboratories were struggling the most with the results obtained when testing quality control strains. Several laboratories (7 in the Acinetobacter spp. panel and 5 in each of the S. aureus, E. coli and K. pneumoniae panels) did not submit results from reference strain testing. For the E. coli EQA round, there were 11 laboratories (9 HH and 2 AH) that did not have deviation in their quality control results. However, all the other laboratories (n=16) presented deviations between 5.9% and 78.6%. Since the same quality control strains were used also for the K. pneumoniae panel, the submitted results were similar. Nine laboratories (8 HH and 1 AH) showed no deviations, while the results from the other 11 laboratories deviated ranging between 6.7% to 37.5%. There was much less heterogeneity in the Acinetobacter spp. panel where the deviations were between 8.3% and 25.0%. The results from the quality control testing also for S. aureus varied substantially between the different laboratories with deviations from the QC ranges between 9.1% and 90.9%.

Not all laboratories from both HH and AH sectors submitted results for ESBL-, AmpC-, or carbapenemase-production for the E. coli and K. pneumoniae isolates. 17 HH (53%) and 5 AH (16%) out of 32 laboratories tested and submitted results for E. coli, while 17 HH (68%) and 3 AH (12%) out of 25 laboratories tested and submitted results for K. pneumoniae.

Overall, the results from this EQAsia show improvement since the last similar EQA trial, EQA6. However, continuous participation in EQA programmes is crucial to maintain quality in a microbiology laboratory, and is a requirement for submission to the World Health Organization (WHO) Global Antimicrobial Resistance and Use Surveillance System (GLASS). Laboratories from both HH and AH sector should continue to participate in training and capacity building activities. Participating laboratories need to make sure they have a good quality management system in place that allows for constant improvement in their routine practice. Providing and maintaining a standardized level of credible diagnostic services would allow laboratories to generate reliable results.

Therefore, laboratories need to ensure they have all necessary quality control strains that should be tested on a regular basis. Furthermore, action needs to be taken every time the results from the quality control testing deviate from the ranges set in the methodological standards used.

A special emphasis needs to be placed also on introducing methods that enable or reinforce the detection of multidrug-resistant pathogens, such as ESBL- and carbapenemase-producing Gram-negatives.