Optimizing antibiotic dosing in critically ill patients is challenging. This study evaluated the discordance rate of antibiotic dosing between the Cockcroft-gault (CG) and chronic kidney disease-epidemiology collaboration (CKD-EPI) estimated glomerular filtration rate (eGFR) equations in medical intensive care units (MICUs) patients. We also assessed the concordance analysis of estimated kidney function and stage of dosing for each antibiotic agent between equations. A retrospective study was conducted on patients in MICUs who received commonly used antibiotic agents between August 2020 and July 2023. The agreement was assessed using a weighted kappa statistic. A total of 171 patients with 266 cystatin C sampling points were included. The mean age and median sarcopenia index were 67.23 years and 0.45, respectively. The CKD-EPI eGFRcys 2012 equation showed the highest discordance in antibiotic dosing. Discordance rate of antibiotic dosing based on CG and CKD-EPI eGFR based on creatinine ranged from 10% to 30%. Compared with cystatin C-based equations, Piperacillin/tazobactam had the highest negative discordance rates, while ertapenem had the lowest. The acute kidney injury group exhibited a reduced correlation and an increased discordance rate of antibiotic agents between creatinine-based and cystatin C-based equations. Various equations for estimating renal clearance from the Kidney Disease: Improving Global Outcomes guideline result in different antibiotic dosages. Further research is required for appropriate dose adjustment.
Sungsana W, Nakaranurack C, Chaijamorn W, Srisawat N. A retrospective observational study on the discordance rate of antibiotic dosing among critically ill patients: Considerations for using KDIGO guideline. J Appl Pharm Sci. 2025. Article in Press. http://doi.org/10.7324/JAPS.2026.259994
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