Background

Current antimicrobial resistance (AMR) surveillance systems, particularly in low- and middle-income countries (LMICs), have significant limitations. They are generally passive, focusing solely on pathogens and relying only on routine antimicrobial susceptibility testing (AST) results from labs. This approach lacks crucial patient-level data, such as clinical syndromes and other relevant metadata, which are essential for creating effective treatment guidelines. Because diagnostic resources are often underutilized and diagnostic stewardship is lacking in LMICs, existing surveillance data is skewed towards drug-resistant infections (DRIs). Consequently, using this biased data to inform treatment guidelines could worsen the AMR problem by promoting overly broad-spectrum antibiotic use, rather than offering targeted solutions.

A more effective approach is integrated, case-based surveillance that combines patient and laboratory data. This addresses the biases of current systems and answers critical patient-level questions that pathogen-focused surveillance cannot, such as:

• What is the patient-level impact and cost of DRIs?
• What patient-level risk factors contribute to DRIs in specific settings?
• Which combinations of AMR and syndromes lead to the worst outcomes for particular patient groups?

Two recent influential studies in The Lancet modeling the burden of AMR underscored the scarcity of high-quality patient-level data, particularly from LMICs. Such data, incorporating key patient-level variables within large datasets, are crucial for accurate modeling, forecasting, and identifying effective interventions.

ACORN addresses this need by providing an operationally efficient, case-based AMR surveillance system designed for low-resource settings. It complements and enhances existing laboratory capacity-building initiatives.

Aims

This project will implement clinical antimicrobial resistance (AMR) surveillance in hospitalized patients with suspected acute bacterial infections across up to 15 hospital sites in nine African and Asian countries. The project has several key goals:

• Characterize drug-resistant infections (DRIs): This includes analysis by clinical syndrome, place of acquisition (community-acquired, hospital-acquired, healthcare-associated), patient group (adult, pediatric, neonatal), and location (specific site, country, and region).
• Determine attributable mortality: Specifically for bloodstream infections caused by extended-spectrum beta-lactamase-producing Escherichia coli and methicillin-resistant Staphylococcus aureus.
• Analyze parenteral antibiotic prescribing practices: This involves identifying the main reasons for prescribing these antibiotics, focusing on patient group, timing of prescription (on admission versus after two days), and location.
• Analyze empiric antibiotic use: This includes examination by clinical syndrome, place of acquisition, patient group, and location.