Success factors of extracorporeal shock wave lithotripsy for renal and upper ureteric calculi in adults

Abstract

Background Extracorporeal shock wave lithotripsy (ESWL) is considered the first-line treatment for most patients with renal and ureteric calculi, as it is safe and noninvasive. Objective The present study was undertaken to evaluate the most significant factors that influence the success rate of ESWL for renal and upper ureteric calculi in adults. Patients and methods This randomized prospective study for adult patients more than or equal to 18 years old included 50 patients with renal stone less than or equal to 2 cm and 50 patients with upper ureteric stone less than or equal to 2 cm. The included patients were treated with ESWL at Al-Zahraa University Hospital and National Institute of Urology and Nephrology between August 2018 and July 2019. Patients with multiple ipsilateral stones, bleeding disorders, impaired renal function, congenital abnormalities, untreated urinary tract infections, have BMI more than 30 kg/m2, pregnant women, and patients with radiolucent stones were excluded from the study. P value less than or equal to 0.05 was taken as the level of significance. Results The overall success of ESWL was 86 (86%), including 81 (94.2%) patients who had total stone clearance. The other five patients had Steinstrasse after the first session. The success rate of ESWL in males was 92.6% compared with 78.3% in females (P=0.040). The success rate of ESWL in patients with stent was 66.77%, whereas the success rate of ESWL in patients without stent was 90.2%, with P value 0.009. The success rate of ESWL in stone density more than 1000 HU was 80.8%, whereas the success rate of ESWL in stone density less than or equal to 1000 HU was 96.97%, with P value of 0.027. Conclusion ESWL should be considered a first-line therapy for treatment in patients with upper urinary tract calculi with density less than or equal to 1000 HU and size up to 20 mm. Stenting should be considered in certain cases when indicated.