Uses of mathematical modeling to estimate the impact of mass drug administration of antibiotics on antimicrobial resistance within and between communities

Modelling the implementation of narrow versus broader spectrum antibiotics in the empiric treatment of E. coli bacteraemia

The implementation of new antimicrobial resistance stewardship programs is crucial in optimizing antibiotic use. However, prescription choices can be difficult during empiric therapy; clinicians must balance the survival benefits of broader spectrum antibiotics with associated increases in resistance. The aim of this study was to evaluate the overall feasibility of switching to narrow spectrum antibiotics during the empiric treatment of E. coli bacteraemia by quantifying changes in resistance rates, antibiotic usage, and mortality using a deterministic state-transition model. Three unique model scenarios (A, B, and C), each representing a progressively broader spectrum empiric treatment regimen, were used to compare outcomes at 5 years. We show that the empiric use of the narrowest spectrum (first-line) antibiotics can lead to reductions in resistance to second-line antibiotics and the use of third-line antibiotics, but they also lead to increases in resistance to first-line therapy and higher mortality. Crucially, we find that shortening the duration of empiric and overall treatment, as well as reducing the baseline mortality rate, are important for increasing the feasibility of switching to narrow spectrum antibiotics in the empiric treatment of E. coli bacteraemia. We provide a flexible model design to investigate optimal treatment approaches for other bacterial infections.

Antibiotic safety among neonates and paediatrics in a public hospital: KwaZulu-Natal

Background

The World Health Organization (WHO) guidelines recommend the empiric treatment of infections before definitive treatment begins. However, ethical concerns limit the availability of clinical trials in neonates and paediatrics to fully ascertain the safety profile of antibiotics in these populations.

Aim

This study aimed to quantify the use of antibiotics among neonates and paediatrics and commented on the use, rationale and appropriateness of antibiotics prescribed.

Setting

A secondary level public sector hospital located in Durban, KwaZulu-Natal.

Methods

Demographic and treatment information of neonates and paediatrics were collected retrospectively from January 2022 to June 2022. Data were obtained from patient files and extracted for analysis using Microsoft Excel®. Analytical and descriptive statistics were used to analyse patient demographics and treatment variables.

Results

A total of 568 antibiotics, issued to 389 patients, were reviewed. Penicillins (40.1%), aminoglycosides (24.3%) and combination penicillin-beta-lactam inhibitors (23.3%) were identified as the most frequently prescribed antibiotics for inpatients. Most antibiotics prescribed to inpatients were for complications associated with pre-term birth (66.9%). Combination penicillin-beta-lactam inhibitors (34.7%), penicillins (29.5%) and cephalosporins (29.5%) were the most frequently prescribed antibiotics to outpatients. A correlation was found between the route of administration and the duration of therapy; the intravenous route (63.6%) was preferred over the oral route (36.4%) for administration.

Conclusion

Many broad-spectrum antibiotics were prescribed, thus increasing the risk of resistance. Antibiotics were being prescribed according to the guidelines; however, there is still a need for therapeutic drug monitoring to ensure the continuation of rational drug use.

Contribution

There was evidence of rational use of antibiotics in the public hospital (KwaZulu-Natal), in keeping with economic and availability factors.

Implementation of A Year-Long Antimicrobial Stewardship Program in A 227-Bed Community Hospital in Southern Italy

BACKGROUND

Healthcare-Acquired Infections (HAIs) are serious healthcare complications affecting hospital stay, in-hospital mortality, and costs. Root cause analysis has identified the inappropriate use of antibiotics as the main causative factor in the expansion of multi-drug-resistant organisms (MDRO) in our hospital. An Antimicrobial Stewardship (AMS) program was implemented to optimize antibiotic use, limit the development of resistance, improve therapeutic efficacy and clinical outcomes, and reduce costs.

METHODS

The stewardship strategies were: antimicrobial oversight on "critical" antibiotics; the development of hospital guidelines on antibiotic selection with the production of a consensus document; the implementation of clinical and management control algorithms with visual impact and Business Intelligence methods; training and updating; and the monitoring of outcome measures and process indicators.

RESULTS

Clinical outcomes: length of stay reduced by 0.23 days, hospital readmission/first month rates decreased by 19%, and mortality for infections reduced by 8.8%. Microbiological Outcomes: Clostridium Difficile colitis incidence reduced by 9.1%.Economic Outcomes: Reduction in antimicrobial costs by 35% on average fee/discharged patient.

CONCLUSIONS

The systematic application of the AMS program in a small hospital led to multiple improvements in clinical, microbiological, and economic outcome measures. The analysis of the core indicators for our hospital AMS program showed a significant adherence to the model and hospital recommendations.