title: Impact of ureteric stent on outcome of extracorporeal shockwave lithotripsy: A propensity score analysis.
abstract: BACKGROUND
  Extracorporeal shockwave lithotripsy (SWL) is one of the most frequently performed procedures in patients with urolithiasis. For ureter-localized stones, SWL is often preceded by a double J stent insertion. However, fear of serious complications, including sepsis associated with stents, is often expressed. The following study assessed the impact of stent insertions on the results of SWL in patients with ureteric stones.
  
  
  METHODS
  The study group consisted of 411 ureteric stone patients who were treated with SWL from January 2010 to December 2014. In 60 cases, treatment was preceded by ureteric stent insertion. A propensity scoring system was used to pair non-stented patients with the stented group. Success rates were assessed and compared using the chi-squared test. Multivariate logistic regression analysis was used to evaluate the influence of particular variables on the stone-free rate.
  
  
  RESULTS
  The overall success rate was 82.2%. After matching, the success rate of the stented group was not significantly different from the control group (85.0% vs. 83.3% respectively, p = 0.80). The mean number of sessions was higher in the stented group (1.88 per patient). Stones located in the lower part of the ureter have the greatest chance of being successfully treated.
  
  
  CONCLUSIONS
  The double J stent has no influence on the outcome of SWL treatment. In view of the greater likelihood of having additional sessions, this approach should be reserved for selected cases.
authors.affiliation: Department of Urology and Urological Oncology, Pomeranian Medical University, Szczecin, Poland.
authors.forename: Krystian
authors.initials: K
authors.lastname: Kaczmarek
authors.affiliation: Department of Urology and Urological Oncology, Pomeranian Medical University, Szczecin, Poland.
authors.forename: Adam
authors.initials: A
authors.lastname: Gołąb
authors.affiliation: Department of Urology and Urological Oncology, Pomeranian Medical University, Szczecin, Poland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Słojewski
keywords: extracorporeal shockwave lithotripsy; stent; stone; ureter