Abstract
Objectives: To assess the adherence of Ghanaian healthcare laboratories to AST standards and to assess discrepancies between breakpoint-defining dosages and recommended doses in Ghanaian National Standard Treatment Guidelines (NSTGs).
Methods: Nineteen laboratories were issued electronic questionnaires regarding AST methods and guidance. NSTG doses and breakpoint-defining dosages were compared to determine the applicability of AST standards.
Results: Eleven of the 19 laboratories responded. Traditional biochemical species identification was the most common method among surveyed laboratories, with disc diffusion being the main AST method. All laboratories reported using CLSI standards. Major quality assurance issues identified regarding AST testing included the use of outdated standards, failure to consistently determine inoculum density, irregular use of quality control strains, and agent limitations on antibiotic disc panels. Discrepancies in definitions for multidrug resistance and the testing of such isolates were also identified.
When comparing recommended NSTG doses to breakpoint-defining dosages, the EUCAST standard had a higher number of doses available for review (30/30, 100% versus 14/30, 47%) and a higher percentage of full agreement (19/30, 63% versus 6/30, 20%) compared with CLSI. Discrepancies between breakpoint-defining and recommended dosages were found for meropenem, ceftriaxone, and amoxicillin-clavulanic acid oral/iv, leading to potential underdosing.
Conclusions: This study highlights the need for rigorous adherence to AST standards and outlines considerations for the adoption of AST standards in a low-middle-income country.
Methods: Nineteen laboratories were issued electronic questionnaires regarding AST methods and guidance. NSTG doses and breakpoint-defining dosages were compared to determine the applicability of AST standards.
Results: Eleven of the 19 laboratories responded. Traditional biochemical species identification was the most common method among surveyed laboratories, with disc diffusion being the main AST method. All laboratories reported using CLSI standards. Major quality assurance issues identified regarding AST testing included the use of outdated standards, failure to consistently determine inoculum density, irregular use of quality control strains, and agent limitations on antibiotic disc panels. Discrepancies in definitions for multidrug resistance and the testing of such isolates were also identified.
When comparing recommended NSTG doses to breakpoint-defining dosages, the EUCAST standard had a higher number of doses available for review (30/30, 100% versus 14/30, 47%) and a higher percentage of full agreement (19/30, 63% versus 6/30, 20%) compared with CLSI. Discrepancies between breakpoint-defining and recommended dosages were found for meropenem, ceftriaxone, and amoxicillin-clavulanic acid oral/iv, leading to potential underdosing.
Conclusions: This study highlights the need for rigorous adherence to AST standards and outlines considerations for the adoption of AST standards in a low-middle-income country.
| Original language | English |
|---|---|
| Journal | Journal of Antimicrobial Chemotherapy |
| Publication status | Accepted/In press - 2 Jan 2026 |