Estimating the burden of antimicrobial resistance in Malawi: protocol for a prospective observational study of the morbidity, mortality and economic cost of third-generation cephalosporin resistant bloodstream infection.

Introduction: Antimicrobial resistance (AMR) is a global public health concern, but the problems are context specific, with each county or setting facing differing challenges. In sub-Saharan Africa, third-generation cephalosporin resistant Enterobacterales (3GCR-E) are of particular concern, given the widespread reliance on ceftriaxone for treatment of severe infection in this setting. In Malawi, despite rising prevalence of 3GCR-E, the health-impact of these infections has not been described. This study is designed to estimate attributable mortality, morbidity and economic cost of 3GCR-E bloodstream infection (BSI) in a large, urban hospital. Methods: This study will investigate the burden of AMR by recruiting a a prospective longitudinal cohort of patients who have bloodstream infection with 3GCR-E, at Queen Elizabeth Central Hospital, Blantyre, Malawi. Patients whose blood culture is positive for either third-generation cephalosporin susceptible (3GC-S) or third-generation resistant (3GC-R) Enterobacterales will be enrolled and provide clinical and healthcare economic data. Patients will be followed throughout their hospital stay and to 6-months post discharge. The primary outcomes for the study are mortality and morbidity from 3GCR-E. Healthcare economic outcomes will be assessed by comparing healthcare provider costs, indirect patient costs and health-related quality of life outcomes in patients with 3GC-S and 3GC-R BSI. Based on our observation that some patients with clinical suspicion of sepsis and 3GC-R BSI are surviving without an effective antibiotic, we review each patient prospectively and classify what role the isolated bacteria is playing in the patient's clinical presentation. Each BSI episode will be classified into the following categories: definite Gram-negative sepsis, probable Gram-negative sepsis, transient or occult bacteraemia, or contaminated blood culture. These classifications will be incorporated into our analysis. Ethics and dissemination: The study protocol has been approved by the Malawi College of Medicine Research Ethics Committee and by the Liverpool School of Tropical Medicine Research Ethics committee.