Background and Objective: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the leading causes of hospital and community-acquired infections, showing antimicrobial resistance (AMR), which is an increasing public health concern. One of the commonly-used methods to evaluate resistance include the Kirby-Bauer disk diffusion method. However, this test is found to be time-consuming, lacking in terms of mechanization and automation, alongside its non-applicability to certain antibiotics such as vancomycin. Thus, the Clinical Laboratory Standards Institute (CLSI) recommends using the broth microdilution method in the evaluation of antibacterial activities against S. aureus. A rapid laboratory identification of MRSA is important in the treatment of patients. Therefore, this study aims to optimize and evaluate the effectiveness of a rapid microplate assay using resazurin dye as a colorimetric indicator in determining antibacterial activity against clinical isolates of MRSA and methicillin-susceptible S. aureus (MSSA). Methods: Clinical isolates of MRSA and MSSA were obtained from the Philippine General Hospital (PGH) Microbiology Section, and American Type Culture Collection (ATCC) controls of both strains (ATCC 25923 and ATCC 43300) were acquired. These were then subjected to identification and confirmation procedures. A standardization of bacterial inoculum was performed by comparing its 24-hr growth in Mueller Hinton Broth to 0.5 McFarland Standard. The resazurin microplate assay (REMA) was set-up using two-fold serial dilution of control antibiotics such as oxacillin, vancomycin, and cefoxitin. Each plate was inoculated with standardized bacterial growth of controls and clinical isolates. To determine the time needed for the reduction of the resazurin dye, a qualitative assessment was conducted by comparing the reaction time between a 6.75 mg/mL dye with a 0.01 mg/mL dye. The plates were also subjected to different incubation times and dye concentrations, and the optical densities of the plates were compared using a microplate reader. Results: Results showed that there were no significant differences between the optical densities of the wells of those incubated for 5 hours and for 24 hours (p >0.05). Furthermore, there was a significant reduction in the reaction time of the dye (from 18 hours to 1 hour) when the dye concentration was reduced from 6.75 mg/mL to 0.01 mg/mL. The optimized REMA showed a significant difference between the minimum inhibitory concentrations (MICs) of the different antibiotics against the control and isolate strains of MRSA and MSSA, showing a W of -2.98 (p <0.05) using the Wilcoxon Rank-Sum non-parametric test. Furthermore, the REMA has shown better illustration of anti-MRSA and anti-MSSA activities as compared to the Kirby Bauer disk diffusion method. Conclusion Based on the results presented, the researchers determined the optimal condition for the resazurin microtiter assay, which was 0.01 g/mL concentration of resazurin dye, at a 5-hour incubation period. This study has shown that an optimized REMA is an efficient and fast method to determine the antimicrobial activities of oxacillin, cefoxitin, and vancomycin against MRSA and MSSA.
Methicillin Resistant Staphylococcus aureus

Objectives The implementation of Philippine National Standard PNS ISO 15189:2013 to support the medical laboratory to produce competent results is a recognised challenge. It is apparent that the approach of ensuring the equipment availability can be specifically optimised. No known research has focused on exploring on the conduct of conformity evaluation of Afinion 2 Analyzer maintainability for the PNS ISO 15189:2013 accredited medical laboratory. The aim of the current study was to develop a practical tool for the medical laboratory to support the internal audit process by determining the compliance status of Afinion 2 Analyzer maintainability.
Accreditation

Objectives: The implementation of Philippine National Standard PNS ISO 15189:2013 to support the medical laboratory to produce competent results is a recognised challenge. It is apparent that the approach of ensuring the equipment availability can be specifically optimised. No known research has focused on exploring on the conduct of conformity evaluation of Afinion 2 Analyzer maintainability for the PNS ISO 15189:2013 accredited medical laboratory. The aim of the current study was to develop a practical tool for the medical laboratory to support the internal audit process by determining the compliance status of Afinion 2 Analyzer maintainability. Methods The relevant conformance requirements in Clauses 4 (Management requirements) and 5 (Technical requirements) of PNS ISO 15189:2013, manufacturer requirements and specific requirements for accreditation from 70/101 (69%) accreditation bodies in 80/249 (32%) countries were identified as specific audit criteria for Afinion 2 Analyzer conformity evaluation checklists for the maintenance and reference equipment.

Objectives: The primary aim of this study was to determine quantitatively the extent of coverage of the Hong Kong Laboratory Accreditation Scheme (HOKLAS 015) requirements by guidance checklists (HOKLAS 016‑02 and HOKLAS 021). Methods: The level of conformance requirement coverage of HOKLAS 015 by HOKLAS 016‑02 and HOKLAS 021 was calculated by an evaluation checklist based on conformance requirements in HOKLAS 015. A distribution analysis of conformance requirements relating to the International Standard ISO 15189:2012 process‑based quality management system model was also performed to elicit further coverage information. Results: HOKLAS 016‑02 was found to provide coverage of 76% while HOKLAS 021 was found to provide coverage of 11%. HOKLAS 015 was also found to have a distribution coverage of 78% relating to the International Standard ISO 15189:2012 process‑based quality management system model. Conclusion The results of this analysis should be of value to medical laboratories wishing to maintain the internal auditability required by HOKLAS 015 by gaining an awareness of the extent of coverage provided by HOKLAS 016‑02 and HOKLAS 021.
Accreditation ; Management Audit