A BSTRACT The overuse of antibiotics has led to various healthcare problems such as the emergence of resistance in infectious microbes and mortality due to antibiotic resistant healthcare associated infections (HAIs). An antimicrobial stewardship (AMS) program is the set of interventions used worldwide to enhance the rational use of antibiotics especially for the hospitalized patients. This review aimed to describe the characteristics of the implemented AMS programs in various hospitals of the world mainly focusing on the interventions and patients outcomes. The literature about AMS program was searched through various databases such as PubMed, Google Scholar, Science Direct, Cochran Library, Ovid (Medline), Web of Science and Scopus. In this review the literature pertaining to the AMS programs for hospitalized patients is sorted on the basis of various interventions that are categorized as formulary restriction (pre-authorization), guideline development, clinical pathway development, educative interventions and prospective audit. Moreover a clear emphasis is laid on the patient outcomes obtained as a result of these interventions namely the infection control, drop in readmission rate, mortality control, resistance control and the control of an overall cost of antibiotic treatment obtained mainly by curbing the overuse of antibiotics within the hospital wards. AMS program is an efficient strategy of pharmacovigilance to rationalize the antimicrobial practice for hospitalized patients as it prevents the misuse of antibiotics, which ultimately retards the health threatening effects of various antibiotics.

Introduction: The high reliance of the physicians and surgeons on the antibiotics since their discovery has led to an irrational antibiotic utilization which not only has raised the incidence of antimicrobial resistance (AMR) but also increased the cost of treatment with antibiotics as high use of antibiotics has been found related to the occurrence of certain nosocomial infections which need extra antibiotic courses to be cured. In order to overcome these antibiotic utilization related problems an antimicrobial stewardship (AMS) program being the set of various persuasive, restrictive and structural interventions is considered an effective tool to rationalize the in-patient antimicrobial utilization worldwide. Method: The focus of this review is on the interventions that are being implemented during the in-patient AMS programs and have been described effective in controlling the antibiotic utilization, their cost of treatment and an overall infection control. The literature containing the information about various AMS interventions effecting the utilization and cost patterns along with the impact on AMR was searched in various databases such as PubMed, Google Scholar, Science Direct, Ovid (Medline) and Scopus. The categorical sorting of the published data is based on various AMS interventions such as the guideline development, formulary restriction (pre-authorization), educative interventions, clinical pathway development and prospective (post prescription) audit. Considering the objectives of the study such as the goal to curb overutilization of antibiotics, control of their cost of treatment for in-patients and infection control the sorted literature is presented in three different tables describing the AMS impact on the said outcomes. Results: The post AMS changes in utilization patterns are described as fall of antibiotics defined daily doses (DDD) and days of therapy (DOT) which resulted in the reduction of the cost of treatment with antibiotics. The reduction of the cost of treatment with antibiotics also resulted due to the AMS impact on the control of various nosocomial and multi-drug resistant (MDR) infections. Conclusion:  It has been concluded that the AMS program if implemented under the supervision of an expert AMS team mainly comprising of an infectious disease (ID) physician, clinical pharmacists and microbiologists with considerable support by the hospital authorities could be a highly efficient tool of the pharmacovigilance for rationalizing the in-patient antimicrobial practice.

Objective: To evaluate the impact of antimicrobial stewardship (AMS) on antibiotic prescribing patterns and certain clinical outcomes, the length of stay (LOS) and the re-admission rate (RR) of the patients treated within the medical ward of a tertiary care hospital in Malaysia. Methods: This quasi-experimental study was conducted retrospectively. The prescriptions of the AMS included alert antibiotics (AA) such as cefepime, ceftazidime, colistin (polymyxin E), imipenem-cilastatin, meropenem, piperacillin-tazobactam and vancomycin were reviewed for the period of 24 mo before (May, 2012–April, 2014) and after (May, 2014–April, 2016) the AMS implementation for the patients who were treated within the medical ward of a Malaysian tertiary care hospital. Patterns of antibiotics prescribed were determined descriptively. The impact of the AMS on the length of stay (LOS) and readmission rate (RR) was determined by the interrupted time series (ITS) comparative analysis of the pre-and post-AMS segments segregated by the point of onset (May, 2014) of the AMS program. Data analysis was performed through autoregressive integrated moving average (ARIMA) Winter Additive model and the Games-Howell non-parametric post hoc test by using IBM Statistical Package for Social Sciences version 25.0 for Windows (SPSS Inc., Chicago, IL, USA). Results: A total of 1716 prescriptions of the AA included for the AMS program showed that cefepime (623, 36.3%) and piperacillin-tazobactam (424, 24.7%) were the most prescribed antibiotics from May 2012 to April 2016. A 23.6% drop in the number of the AA prescriptions was observed during the 24-month post-AMS period. The LOS of the patients using any of the AA showed a post-AMS decline by 3.5 d. The patients’ LOS showed an average reduction of 0.12 (95% CI, 0.05–0.19, P=0.001) with the level and slope change of 0.18 (95% CI, 0.04–0.32, P=0.02) and 0.074 (95% CI, 0.02–0.12, P=0.002), respectively. Similarly, the percent RR reduced from 20.0 to 9.85 during the 24-month post-AMS period. The observed post-AMS mean monthly reduction of the RR for the patients using any AA was 0.38 (95% CI, 0.23–0.53, P<0.001) with the level and slope change of 0.33 (95% CI, 0.14–0.51, P=0.02) and 0.37 (95% CI, 0.16–0.58, P=0.001), respectively. Conclusion: The AMS program of a Malaysian tertiary care hospital was a coordinated set of interventions implemented by the AMS team of the hospital that comprised of the infectious diseases (ID) physician, clinical pharmacists and microbiologist. The successful implementation of the AMS program from May, 2014 to April, 2016 within the medical ward resulted in the drop of the number of AA prescriptions that sequentially resulted in the significant (P<0.05) post-AMS reduction of the LOS and the RR.