Antibiotic utility and susceptibility changes of multidrug-resistant Escherichia coli and Klebsiella spp: 5-year experience in a tertiary healthcare centre.

OBJECTIVES: Multiple studies have identified cross-sectional relationships between antibiotic use and bacterial resistance. The aim of this study was to analyse the susceptibility of multidrug-resistant (MDR) and non-MDR (nMDR) isolates of Escherichia coli and Klebsiella spp to cephalosporins: ceftazidime (CTZ), ceftriaxone (CTX), cefepime (CEF) and fluoroquinolones: ciprofloxacin (CIP) and levofloxacin (LEV) in a tertiary healthcare centre from 2014 to 2018. In addition, we aimed to evaluate a correlation between the antibiotic utility and susceptibility of the selected enterobacteria. METHODS: Antibiotics consumption and antimicrobial resistance were monitored in a tertiary care university hospital from 2014 to 2018. Utilisation of antibiotics in the observed period was expressed as defined daily dose (DDD) per 100 bed/days (DBD). Bacterial susceptibility was reported as the percentage of susceptible results among all tested isolates from all patient samples. In further analysis, bacterial strains were considered as MDR or nMDR species. An MDR bacterial strain was defined as one with acquired non-susceptibility to at least one agent in three or more antimicrobial categories. RESULTS: Our results suggest that cephalosporins were the most used antibiotics, followed by fluoroquinolones, during the entire observed period 2014-2018. Our findings show that MDR isolates of E. coli had an increasing trend in susceptibility in relation to CTX (p=0.005), whereas a decreasing trend was observed for MDR isolates of E. coli susceptibility towards CIP and LEV (p<0.001). Klebsiella spp susceptibility for MDR isolates showed a decreasing trend in relation to CEF (p<0.001) and both fluoroquinolones (p<0.001). A significant negative association between CEF consumption and Klebsiella spp MDR isolates susceptibility was observed (p=0.045). CONCLUSION: Implementation of antimicrobial stewardship programmes with early detection and close monitoring of MDR bacterial strains of E. coli and Klebsiella spp may be a crucial step in reducing the menace of antimicrobial resistance, which is now a global problem.

[Collateral damage and hospital infections].

COLLATERAL DAMAGE: Implies negative ecological effects of antibiotic therapy, characterized by the selection of resistant microorganisms and adverse colonization or injections with their multi-resistant species. MICROBIAL RESISTANCE: Is mediated by various mechanisms, the presence of which is determined by the nature of antibiotic effects and origin of the agent. Its most important aspect is multiple resistance, most commonly conditioned by the presence of several different resistance genes localized in the form of common units on gene transport elements (integrons, transposons, plasmids). It is further developed by way of mutation-guided alterations in the environments with a strong, selective antibiotic pressure, such as hospital conditions. HOSPITAL INFECTIONS: Bacteremias and pneumonias, above all, are nowadays the principal cause of hospital morbidity and mortality. More than 70% of agents causing them are resistant to at least one of the antibiotics to which they were sensitive once, and multi-resistance is their very common feature as well. Currently valid recommendations for the treatment of nosocomial bacteremias and pneumonias are the empirical application of broad spectrum antibiotics, de-escalation treatment, short therapy course. use of bactericidal antibiotics, and optimization of their pharmacodynamics. in that regard, a combined treatment with carbapenems and glycopeptides reduces the probability of inadequate onset of treatment and the risk of further development of microbial resistance (in some cases it also mediates the establishment of earlier sensitivity), it shortens treatment time, and reduces treatment costs. Further improvement of such a treatment involves a possible adjustment to the well known and regularly monitored local incidence and resistance of microbial agents.