Predictive factors of extracorporeal shock wave lithotripsy failure in the treatment of patients with ureterolithiasis

Abstract

Efficacy of different approaches to the treatment in patients with ureteral calculi and predictive factors for the success are the objects of contemporary studies. However, only few on them studied the duration factor of typical ureterolithiasis symptoms and changes of the ureter wall as predictive factors of extracorporeal shock wave lithotripsy (ESWL) failure in patients with ureteral stones. The aim of the study was to determine the peculiarities of histological changes in the ureter wall as a result of calculus presence and to evaluate the predictive factors of ESWL failure in patients with ureterolithiasis. Materials and methods. An analysis of the treatment by ESWL in 662 patients with ureterolithiasis was performed. The patients were divided into two groups: Group 1, n = 629 (95.0 %) individuals with effective ESWL and Group 2, n = 33 (5.0 %) patients with ESWL failure when calculi were not eliminated. Stones were found in 378 (57.0 %) patients in the upper third of the ureter, in 50 (7.6 %) – in the middle and in 234 (35.4 %) – in the lower third. For determining the predictors of ESWL failure, the Spearman’s Rank Correlation Coefficient was used. Results. The overall ESWL efficacy in our study was 95.0 %. The strong inverse correlation was found between the ESWL success and duration of symptoms (r = -0.92) and stone size (r = -0.68). Stone localization in the ureter did not influence the ESWL outcomes (r = 0.27). Conclusions. Increasing of the period from the manifestation of primary clinical symptoms to the implementation of ESWL reduces the treatment efficacy. Patients with ureteral stones more than 15 mm have lower stone-free rates after ESWL.

Keywords

• ureterolithiasis
• treatment
• extracorporeal shockwave lithotripsy
• predictors