Diagnostic Stewardship for Combating Antimicrobial Resistance in Resource-Limited Healthcare Settings: From Better Testing to Better Treatment
Abstract
Background: Antimicrobial resistance (AMR) is sustained not only by inappropriate antimicrobial use but also by diagnostic failure. Unnecessary testing can trigger treatment of colonization or contamination, whereas absent, delayed, or poorly communicated testing encourages prolonged empirical broad-spectrum therapy. Diagnostic stewardship seeks to ensure that the right test is obtained from the right patient, at the right time, and that its result is interpreted and acted upon correctly.Objective: To synthesize the role of diagnostic stewardship in AMR control, with emphasis on implementation in resource-limited healthcare settings. Methods: A targeted narrative review of peer-reviewed literature and World Health Organization guidance published primarily from 2015 through October 2026 was undertaken. Evidence concerning conventional microbiology, biomarkers, rapid and point-of-care tests, clinical decision support, laboratory strengthening, and linkage with antimicrobial stewardship was prioritized. Findings: Diagnostic tools have greatest clinical value when embedded in a pathway that links appropriate test selection and specimen quality to timely reporting and antimicrobial-stewardship action. Rapid tests paired with stewardship can shorten time to optimal treatment and may improve survival in bloodstream infection. Lower-cost approaches—including specimen criteria, reflex testing, selective reporting, clinical decision support, and locally adapted laboratory quality systems—can reduce low-value testing and improve use of existing capacity. Major constraints include weak laboratory infrastructure, supply instability, workforce shortages, fragmented clinical-laboratory communication, and limited evaluation of patient-centered outcomes. Conclusion: Diagnostic stewardship should be treated as a clinical system rather than a technology-purchasing exercise. Resource-limited facilities can begin with high-burden syndromes, strengthen the pre-analytic and post-analytic pathway, connect results to treatment decisions, and monitor safety alongside antimicrobial use.