No abstract

m-URS is an effective, safe, and reproducible technique that minimizes surgical aggression to the ureteral anatomy. Satisfactory and comparable results to "conventional" ureteroscopy were obtained in the treatment of distal ureteral stones in women, although clinical trials are needed. The reduction of the ureteral damage may reduce secondary procedures and increase the cost-effectiveness of the procedure.

Purpose of reviewThe process of renal stone formation is complex, multifactorial, and variable depending on the type of stone. The microbiome, whether by direct or indirect action, is a factor that both promotes the formation and protects from developing of renal stones. It is a highly variable factor due to the great interindividual and intraindividual variability that it presents. In recent years, with the incorporation of nonculture-based techniques such as the high-throughput sequencing of 16S rRNA bacterian gene, both intestinal and urinary microbiota have been deeply studied in various diseases such as the kidney stone disease. Recent findingsThis review has examined the new insights on the influence of the intestinal and urinary microbiome in nephrolithiasis disease and its usefulness as a diagnostic and prognostic tool, highlighting its contribution to the pathogenesis, its ability to modulate it and to influence disease development.

Background: Urinary stones disease is becoming more common not only in adults but also in children. Most cases are resolved with extracorporeal shock wave lithotripsy, but miniaturization of endoscopes has increased the use of ureteroscopy in resolving ureteral stones, most notably in children.Case Presentation: This presentation focuses on two cases of microureteroscopy. In both cases, the presence of lithiasis in the pelvic ureter was suspected to be the cause of ureter hydronephrosis, and a microureteroscopy was performed for treatment purposes. MicroPerc set 4.85F sheath was used to explore the pelvic ureter, thus avoiding the need to dilate the ureteral meatus or having to use the safety guide. Patients did not require a postoperative stent and were discharged within 24 hours of the procedure.Conclusion: Use of microureteroscopy proved satisfactory in the two cases of children and it allows diagnosis and treatment of ureteral pathology in pediatric patients.

Miniaturization of ureteroscopy materials is intended to decrease tissue damage. However, tissue hypoxia and the gross and microscopic effects on tissue have not been adequately assessed. We compared the gross and microscopic effects of micro-ureteroscopy (m-URS) and conventional ureteroscopy (URS) on the urinary tract. We employed 14 pigs of the Large White race. URS was performed in one of the ureters with an 8/9.8 F ureteroscope, while a 4.85 F m-URS sheath was used in the contralateral ureter. Gross assessment of ureteral wall damage and ureteral orifice damage was performed. For microscopic assessment hematoxylin-eosin staining and immunohistochemistry for detection of tissue hypoxia were conducted. Regarding the macroscopic assessment of ureteral damage, substantial and significant differences were recorded using URS (C = 0.8), but not with m-URS. Microscopic assessment after staining with hematoxylin-eosin revealed greater epithelial desquamation in the URS group (p < 0.05). Pimonidazole staining revealed greater hypoxia in the epithelial cells than in the remainder of the ureteral layers. We conclude that m-URS causes less damage to the ureteral orifice than URS. Histopathological findings show m-URS reduces ureteral epithelial damage compared with conventional ureteroscopy. Both URS and m-URS cause cellular hypoxia.