Sen H et al., 2019: Results of minimally invasive procedures for ESWL refractory renal stones smaller than 2 cm: A single center experience
Sen H, Baturu M, Bayrak O, Seckiner I, Seckiner I, Erturhan S
Department of Urology . Gaziantep University. Gaziantep. Turkey
OBJECTIVES: To evaluate the efficacy and reliability of endourological procedures in patients with renal stones up to 2 cm that were found to be resistant to extracorporeal shock wave lithotripsy (ESWL). METHODS: 611 patients, who had undergone ESWL due to renal stones up to 2 cm at the ESWL unit of our clinic, were retrospectively evaluated. Standard percutaneous nephrolithotomy (PNL), micro-PNL, retrograde intrarenal surgery (RIRS) was performed on the patients who had stones resistant to ESWL. Demographic data, stone free rate, duration of hospital stay, duration of operation, the duration of scopy, the rates of transfusion and the complications were recorded. RESULTS: The mean age of 611 patients included to the current study was 40.76±15.45 years, the mean size of stones was calculated as 205.47±90.5 mm2.While the renal stones were removed in 468 patients(76.59%) after ESWL, endourological procedures were performed in 142 patients (23.24%) who had ESWL resistant stones. Standard PNL was performed in 73patients (51.4%), RIRS was performed in 51 patients (35.91%), micro-PNL was performed in 18 patients (12.68%). The success rates after the surgical procedures were 93.15%, 90.16% and 88.88%, respectively. No major complication was observed in patient groups who had undergone RIRS and microPNL. CONCLUSION: The surgical approaches, which are selected according to the size and localization of stones, could provide a success rate of 98.03% in ESWL resistant stones and these procedures could be reliably performed with considerably lower complication rates.
Arch Esp Urol. 2019 Jan;72(1):61-68. English, Spanish.
It is of note that the authors used different descriptions of the SWL result: complete stone disintegration, complete stone clearance and SWL-resistant stones. It is difficult to fully understand and follow which patients were included in the latter category. Although it is stated in the conclusion that 98% of patients with stones ho had well disintegrated residual fragments in the patient category with “resistant stones”. If the data presented are used to calculate the proportion of really resistant stones, we get 2% only (100% - 98%). The remaining patients were either stone-free or had well disintegrated stones (fragments). Information on how often the unfavorable lower calyx anatomy was encountered is not provided.
The question is how necessary it was to follow up the SWL treatment with endoscopic stone/fragment removal? Steinstrasse as observed in 7% of the patients and we are told that these patients had fragments removed with rigid ureteroscopy. My own experience is that repeated SWL directed towards the steinstrasse can be used to handle this problem in the vast majority of cases.
It is not mentioned which type of lithotripter that was used, only that the device was electrohydraulic. Slightly surprising is the large mean number of sessions that was carried out; 2.6 both in patients rendered stone-free and in those with residuals.
The serious drawback in the series of treatments was the immuno-suppressed patient with single kidney who died in sepsis. The stone size is not mentioned, but retrospectively it seems as both a stent and pre-treatment with a broad-spectrum antibiotic had been of value, given the high risk of complication in a patient with immunodeficiency and with only one kidney.