In Vitro Susceptibility of Clinical Isolates to Ceftriaxone Alone and Ceftriaxone in Combination With Sulbactam or Tazobactam: A Comparative Study of Broad-Spectrum β-Lactam Antibiotics in India

Background This study was designed to evaluate the current in vitro susceptibility of clinical isolates broad-spectrum β-lactam antibiotics. Methodology Bacterial isolates, cultured from 180 non-repetitive samples between April and November 2022 at three hospitals India, were used minimum inhibitory concentration (MIC) antibiotics using Epsilometer test (E-test) method. Test ceftriaxone combination with β-lactamase inhibitors (BLIs) sulbactam tazobactam. Comparator included amoxicillin + BLI clavulanic acid, piperacillin tazobactam, cefotaxime, cefepime. The MIC values obtained assess compute efficacy ratios (ERs) Results Among ~89% gram-negative bacteria, most prevalent ones being Escherichia coli Klebsiella pneumoniae. Of ~37% susceptible/intermediately susceptible ceftriaxone, ~29% BLIs. had ER >10 against 85%-95% E. whereas comparator 31%-68% isolates. differences tazobactam or cefotaxime statistically significant. Ceftriaxone, sulbactam, 78%, 100%, 90% K. pneumoniae while corresponding percentages for cefepime 64%, 80%, respectively. difference BLIs Ceftriaxone all producing extended-spectrum β-lactamases (ESBLs); percentage significantly higher than that ESBL-producing isolates; ranging 6-10. Conclusions are promising explore infectious microorganisms such as also holds promise variants.