A nomogram to determine the effectiveness of remote shock wave lithotripsy in children with urolithiasis

Abstract

Introduction. The method of choice in the treatment of urolithiasis in children is remote shock wave lithotripsy (RSWL). Due to the vastness of the indications, the effectiveness of this method does not correspond to the expected one, which led to the search for predictive factors of the success of the RSWL and the creation of nomograms to determine its effectiveness. The aim of the work is to identify significant factors influencing the success of remote shock wave lithotripsy and to develop a nomogram to determine its effectiveness in children with urolithiasis. Materials and methods. Two hundred seventy nine patients (305 renal units) with renal urolithiasis were examined. The median age of the patients was 119 (44–175) months. All patients underwent a comprehensive examination. The RSWL is completed. The criterion for the effectiveness of RSWL was the absence of fragments of concretions > 3 mm in the urinary tract during a control ultrasound performed after 3 months. The data of patients between groups with successful and ineffective RSWL were compared according to the following parameters: gender, age, body mass index, presence of surgical interventions, distance from skin to stone, side of the lesion, two-sidedness of the process, exact localization of concretions, their number, size, volume, and density. Results. The parameters that have a positive effect on the outcome of RSWL are: female gender, two-sided process, location in one renal compartment, smaller size, volume and density of the stone. The effect of lithotripsy is advers affected by the age of patients from 6 to 14 years, the location of the stone in the lower group of cups. To create a nomogram, variables were selected using logistic regression analysis in accordance with the clinical and statistical significance of each of factors with a deviation of less effective signs. The final nomogram included the following variables: gender, age, exact location, multiplicity of location, and average density, size and volume of stones according to computed tomography (CT) data. Conclusion. The developed by us nomogram to determine the effectiveness of RSWL is a preoperative planning tool that allows for a personalized and objective approach to the treatment of sick children with urolithiasis. The introduction of such tools into clinical practice for evaluating the effectiveness of operations will optimize the choice of an adequate method of treating patients, increase the effectiveness of operations, reduce the number of additional surgical and anesthetic aids and the duration of the child’s stay in the hospital.