VERIFICATION THE AUTOMATED IDENTIFICATION AND ANTIBIOTIC SUSCEPTIBILITY TESTING SYSTEM IN BACTERIAL TESTING AT NGUYEN TRI PHUONG HOSPITAL

Thu Hương Đặng, Quang Huy Nguyễn, Minh Hà Nguyễn

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Abstract

Introduction: Currently, many automated identification and antimicrobial susceptibility testing systems have been implemented to improve the efficiency and quality of microbiology culture testing, thereby contributing to enhanced treatment outcomes and reducing the risk of drug resistance. Before being applied in routine laboratory practice at healthcare facilities, these automated systems must undergo validation to confirm their intended use. Objective: To determine the correlation and repeatability of the Sentitire Aris HIQ automated bacterial identification and antibiotic susceptibility testing system (Thermo Fisher Scientific, USA) according to the guidelines of CLSI M52-ED1. Subjects and methods: This cross-sectional descriptive study was conducted on clinical bacterial strains and reference strains (ATCC) stored at -80℃ in the Microbiology Unit of Nguyen Tri Phuong Hospital from July 15, 2024 to August 25, 2024. For bacterial identification techniques, the similarity and repeatability were determined between the manual identification method using a manual biochemical kit (Nam Khoa, Vietnam) currently applied at the hospital and the automated system. For antibiotic susceptibility testing, similarity was determined using parameters such as Category Agreement (CA), Very Major Error (VME), Major Error (ME), and repeatability between the Kirby-Bauer disk diffusion susceptibility method currently in use and the automated system. Results: For the identification method, the correlation and repeatability of the Sentitire Aris HIQ automated identification system both achieved 100% for both Gram-negative and Gram-positive bacteria. Notably, the Sentitire Aris HIQ system identified more accurately to species-level within the coagulase-negative Staphylococcus group. For the antibiotic susceptibility testing method, the similarity results for each antibiotic met all evaluation criteria. Among these, the similarity parameters for Gram-negative bacteria were higher than those for Gram-positive bacteria. Specifically, for Gram-positive bacteria, the category agreement was 97.8% (404/413), with 0.7% ME (3/413), 1.5% mE (6/413), and no VME recorded. For Gram-negative bacteria, the category agreement was 98.5% (605/614), with 0.5% ME (3/614), 1% mE (6/614), and no VME recorded. The repeatability for antibiotics across the test strains achieved 100%. Conclusions: The Sensititre system operates effectively, meeting the requirements for identification and susceptibility pattern of aerobic bacteria in routine microbiology laboratories, and is suitable for implementation in clinical microbiology laboratory practices at the hospital.

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References

World Health Organization, https://www.who. int/news-room/fact-sheets/detail/antimicrobial-resistance Antimicrobial resistance. 2024.
2. Bộ Y tế., Quyết định số 2429/QĐ-BYT ngày 12 tháng 06 năm 2017 của Bộ trưởng Bộ Y tế về việc ban hành tiêu chí đánh giá mức chất lượng phòng xét nghiệm y học.
3. Clinical & Laboratory Standards Institute M100, Performance Standards for Antimicrobial Susceptibility Testing - 34th Edition. 2024.
4. Clinical & Laboratory Standards Institute M52-ED1, Verification of Commercial Microbial Identification and Antimicrobial Susceptibility Testing Systems, 1st Edition. 2015.
5. Chapin, K.C. and M.C. Musgnug, Validation of the automated reading and incubation system with Sensititre plates for antimicrobial susceptibility testing. Journal of clinical microbiology, 2003. 41(5): p. 1951-1956.
6. Chapin, K.C. and M.C. Musgnug, Evaluation of Sensititre automated reading and incubation system for automated reading of Sensititre broth microdilution susceptibility plates. Journal of clinical microbiology, 2004. 42(2): p. 909-911.
7. Tan YE, Ng LS, Tan TY. Evaluation of Enterococcus faecalis clinical isolates with 'penicillin-resistant, ampicillin-susceptible' phenotype as reported by Vitek-2 Compact system. Pathology. 2014 Oct;46(6):544-50. doi: 10.1097/PAT.0000000000000146. PMID: 25158809.
8. Al-Rawahi, G.N., et al., Performance of the BD Phoenix Automated Microbiology System for Trimethoprim-Sulfamethoxazole Susceptibility Testing of Staphylococcus aureus. Journal of Clinical Microbiology, 2019. 58(1): p. 10.1128/jcm.00994-19.