BACKGROUND: Complicated UTIs (cUTIs) serve as a model for assessing the efficacy and safety of novel antimicrobial therapies targeting multi-drug resistant organisms (MDROs). Few studies have evaluated the burden of cUTI and acute pyelonephritis (AP), including those caused by MDROs. We aim to identify evidence gaps regarding cUTI/AP burden in key countries.
METHODS: In July 2023, a systematic literature review was conducted using PubMed, Embase, Cochrane and EconLit databases. Our searches identified observational studies evaluating cUTI/AP epidemiology, microbiological causes, economic and humanistic burden, and treatment patterns/outcomes within the last decade from China, Europe, France, Italy, Germany, Japan, Spain, United Kingdom (UK), and United States (US) (PROSPERO-CRD42023454794).
RESULTS: Of 1,041 studies identified, 154 were selected for full-text review; 118 studies met the inclusion criteria. Thirty studies provided prevalence or incidence of cUTI/AP with most conducted in the US (n=22). The definitions used to define cUTIs/AP varied. Only 2 studies provided national prevalence/incidence: a 2017 US study in adults estimated the national incidence (4.9 cases/1000 person-years) and prevalence (1.14%); a study of French women reported an incidence of 730 cases/100,000 women. Estimates for cUTI in individuals with catheters (CAUTI) were reported in various countries. Epidemiology data for Germany, UK and China were absent. Causative pathogens were well characterized and included MDROs; the most common pathogen in hospitalized patients was E. coli (22.6%-88.4%), Klebsiella spp. (4.7%-45%) and Pseudomonas aeruginosa (4.3%-41.5%). No studies evaluating humanistic burden were identified, despite the impact of these conditions on patient’s quality of life. Fifty-three economic studies evaluated direct costs (n=22) and/or healthcare utilization (n=51). Mean hospitalizations costs per cUTI varied widely by country, from $2,328 in China to $23,400 for hospital-acquired CAUTI in US children. The highest costs were observed in patients with MDROs. Total healthcare costs, including readmission expenses were missing. No cost estimates for cUTI were identified for France, Japan, Germany or the UK.
CONCLUSION: Substantial knowledge gaps persist in the literature regarding cUTI, including epidemiologic, humanistic, and economic burden studies in key countries. Addressing these gaps is crucial to assessing the added value of novel antibiotics targeting MDROs.
