title: Economic analysis of continuous antibiotic prophylaxis for prevention of urinary tract infections in infants with high-grade hydronephrosis.
abstract: BACKGROUND
  For infants with hydronephrosis, continuous antibiotic prophylaxis (CAP) may reduce urinary tract infections (UTIs); however, its value remains controversial. Recent studies have suggested that neonates with severe obstructive hydronephrosis are at an increased risk of UTIs, and support the use of CAP. Other studies have demonstrated the negligible risk for UTIs in the setting of suspected ureteropelvic junction obstruction and have highlighted the limited role of CAP in hydronephrosis. Furthermore, economic studies in this patient population have been sparse.
  
  
  OBJECTIVE
  This study aimed to evaluate whether the use of CAP is an efficient expenditure for preventing UTIs in children with high-grade hydronephrosis within the first 2 years of life.
  
  
  METHODS
  A decision model was used to estimate expected costs, clinical outcomes and quality-adjusted life years (QALYs) of CAP versus no CAP (Fig. 1). Cost data were collected from provincial databases and converted to 2013 Canadian dollars (CAD). Estimates of risks and health utility values were extracted from published literature. The analysis was performed over a time horizon of 2 years. One-way and probabilistic sensitivity analyses were carried out to assess uncertainty and robustness.
  
  
  RESULTS
  Overall, CAP use was less costly and provided a minimal increase in health utility when compared to no CAP (Table). The mean cost over two years for CAP and no CAP was CAD$1571.19 and CAD$1956.44, respectively. The use of CAP reduced outpatient-managed UTIs by 0.21 infections and UTIs requiring hospitalization by 0.04 infections over 2 years. Cost-utility analysis revealed an increase of 0.0001 QALYs/year when using CAP. The CAP arm exhibited strong dominance over no CAP in all sensitivity analyses and across all willingness-to-pay thresholds.
  
  
  CONCLUSIONS
  The use of CAP exhibited strong dominance in the economic evaluation, despite a small gain of 0.0001 QALYs/year. Whether this slight gain is clinically significant remains to be determined. However, small QALY gains have been reported in other pediatric economic evaluations. Strengths of this study included the use of data from a recent systematic review and meta-analysis, in addition to a comprehensive probabilistic sensitivity analysis. Limitations of this study included the use of estimates for UTI probabilities in the second year of life and health utility values, given that they were lacking in the literature. Spontaneous resolution of hydronephrosis and surgical management were also not implemented in this model.
  
  
  CONCLUSIONS
  To prevent UTIs within the first 2 years of life in infants with high-grade hydronephrosis, this probabilistic model has shown that CAP use is a prudent expenditure of healthcare resources when compared to no CAP.
authors.affiliation: Division of Urology, St. Josephs Healthcare, Institute of Urology, 50 Charlton Avenue East, Room G344, Hamilton, Ontario, L8N 4A6, Canada; Division of Urology, Department of Surgery, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4L8, Canada.
authors.forename: H Y V
authors.initials: HY
authors.lastname: Tu
authors.affiliation: McMaster Pediatric Surgery Research Collaborative, Department of Surgery, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4L8, Canada; Department of Clinical Epidemiology and Biostatistics, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4L8, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Pemberton
authors.affiliation: Division of Urology - Main Office, Main Floor Black Wing Room M299, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, Ontario, M5G 1X8, Canada.
authors.forename: A J
authors.initials: AJ
authors.lastname: Lorenzo
authors.affiliation: Division of Urology, St. Josephs Healthcare, Institute of Urology, 50 Charlton Avenue East, Room G344, Hamilton, Ontario, L8N 4A6, Canada; Division of Urology, Department of Surgery, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4L8, Canada; McMaster Pediatric Surgery Research Collaborative, Department of Surgery, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4L8, Canada; Department of Clinical Epidemiology and Biostatistics, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4L8, Canada. Electronic address: braga@mcmaster.ca.
authors.forename: L H
authors.initials: LH
authors.lastname: Braga
mesh_terms: D000900:Anti-Bacterial Agents / Q000191:economics / Q000627:therapeutic use*; D019072:Antibiotic Prophylaxis / Q000191:economics*; D017281:Cost of Illness; D003365:Costs and Cost Analysis; D003661:Decision Support Techniques; D006801:Humans; D006869:Hydronephrosis / Q000150:complications* / Q000191:economics / Q000453:epidemiology; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D018803:Models, Economic; D009864:Ontario / Q000453:epidemiology; D014552:Urinary Tract Infections / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*
chemical_list: D000900:Anti-Bacterial Agents
keywords: Antibiotic prophylaxis; Cost-effectiveness analysis; Hydronephrosis; Urinary tract infection