Background and Purpose: Development of flexible renoureteroscopy had a significant impact on the diagnosis and management of upper urinary tract pathology. The aim of our study was to compare the performances of a fiberoptic flexible ureteroscope (FFU) with those of a digital flexible ureteroscope (DFU). Material and Methods: We compared the maneuverability, visibility, and fragility of a Storz 11274AA FFU and of an Olympus URF-Vo DFU. In 44 diagnostic retrograde procedures (22 with FFU and 22 with DFU), the maneuverability and visibility were evaluated with a score ranging from 1 to 5. The success of the inferior calix approach, maximal deflection, irrigation flow, and the endoscopes' fatigability were also compared. Results: FFU and DFU received mean scores of 3.64 vs 4.27 for maneuverability and 3.27 vs 4.68 for visibility. In four cases, acute infundibulopelvic angle and long infundibulum prevented the inferior calix approach with FFU. In two cases, the approach of the narrow infundibulum was impossible using DFU. The normal/pressure irrigation flow through FFU and DFU was 54/144 vs 60/150 mL/min with an empty working channel, decreasing to almost 0 mL/min with 3F instruments inserted. The maximal deflection loss of FFU and DFU ranged between 8% to 50.6% vs 0% to 21.1%, depending on the accessory instrument inserted through the working channel. After 22 procedures, the deflection loss was 10 degrees for the FFU and 0 degrees for the DFU. Conclusions: DFU proved to have superior maneuverability and visibility, which may translate into improved performances. The larger tip of the DFU may decrease its accessibility, especially in narrow segments of the upper urinary tract.

Urinary tract infections (UTIs) represent a frequent pathology among the female population that has become more and more difficult to treat in the past decade, considering the increase in antibiotic resistance—a serious global public health problem. A cross-sectional retrospective study was conducted for six months to report an update regarding the rates of resistance and susceptibility of uropathogens necessary for optimal treatment. A total of 5487 patients were screened, of which 524 (9.54%) were female patients who met the criteria for inclusion in the study. Escherichia coli was the most common pathogen, representing 290 cases (55.34%), followed by Enterococcus spp. 82 (15.64%). Escherichia coli presented the highest resistance to amoxicillin-clavulanic acid (R = 33.1%), followed by trimethoprim-sulfamethoxazole (R = 32.41%) and levofloxacin (R = 32.06%). The highest sensitivity rates were observed for fosfomycin (S = 96.55%), followed by imipenem (S = 93.1%). Enterococcus spp. showed the highest resistance to levofloxacin (R = 50.0%), followed by penicillin (R = 39.02%). The highest sensitivity was observed for fosfomycin (S = 90.24%), linezolid (S = 89.02%), and nitrofurantoin (S = 86.58%). The second most frequent Gram-negative uropathogen was represented by Klebsiella spp., which had the highest resistance to amoxicillin-clavulanic acid (R = 35.89%), followed by levofloxacin (R = 25.64) and trimethoprim-suflamethoxazole (R = 24.35%). The most frequently associated pathology was an episode of UTI in the previous year, followed by diabetes and chronic kidney disease. Antibiotic resistance is a serious problem for all clinicians who treat UTIs. An up-to-date knowledge of antibiotic resistance rates is a major necessity to stop its evolution. Overall, the highest resistance rates were observed for aminopenicillins, fluoroquinolones, and trimethoprim-sulfamethoxazole. The best susceptibility rates were observed for fosfomycin, nitrofurantoin, and carbapenems. Our report aims to guide clinicians whenever they are forced to prescribe antibiotics empirically.

The formation of kidney stones is a complex biologic process involving interactions among genetic, anatomic, dietary, and environmental factors. Traditional lithogenic models were based on urine supersaturation in relation to the activity of crystallization promoters and inhibitors. However, modern research has added new principles such as the “renal epithelial cell response” and the role of inflammation and oxidative stress leading to the development of a “multi-hit hypothesis”. A strong correlation between urinary stones and kidney damage has been well demonstrated by both cohort and case-control studies. The main contributors to chronic kidney damage associated with urinary stones include crystal deposition within the renal parenchyma, associated comorbidities, repeated obstructive and infectious episodes, as well as the potential adverse effects of stone removal procedures. Most hereditary stones may cause high urinary saturation levels promoting obstruction of the Bellini ducts and consequent glomerulosclerosis and interstitial fibrosis in the cortex. These include hereditary hypercalciurias, primary hyperoxalurias, cystinuria, adenine phosphoribosyltransferase (APRT) deficiency (associated with 2,8-dihydroxyadenine lithiasis) and xanthinuria. Complete distal renal tubular acidosis occurs in childhood and presents deafness, rickets, and a short life expectancy. The incomplete form usually manifests in adulthood, primarily with recurrent urinary lithiasis, and less frequently with nephrocalcinosis. In all stone formers stone analysis and a basic metabolic evaluation, including blood biochemistry, urine sediment examination, urinary pH and culture are mandatory, in contrast high-risk stone formers require a more specific metabolic evaluation, including a 24-hour urine sample to measure calcium, phosphate, citrate, oxalate, uric acid, magnesium, sodium and proteinuria. The morpho compositional analysis of kidney stones offers essential insights beyond merely identifying their predominant chemical component. This approach reveals key aspets of the stone formation, such as nucleation sites, crystal growth patterns, and the presence of specific lithogenic processes. The ideal analytical protocol combines stereoscopic microscopy (StM), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and, when necessary, Fourier-transform infrared spectroscopy (FTIR). Recurrence prevention and managing residual fragments require complementary strategies such as lifestyle modifications, dietary interventions, and pharmacological therapies. Among pharmacological options, alkaline citrate salts, particularly potassium citrate, are widely used due to their ability to modify urinary chemistry and inhibit stone formation. Recently, novel molecules have been introduced into the management of renal stone disease. Phytate a naturally occurring polyphosphorylated carbohydrate, exibits a potent inhibitory effect on calcium salt’s nucleation, growth, and aggregation. Theobromine, another natural compound, has been shown to effectively inhibit uric acid crystallization. The co-administration of urinary alkalinizing agents, such as potassium citrate, alongside theobromine has been proposed as a therapeutic strategy to optimize uric acid solubility and to reduce the risk of excessive alkalinization and subsequent sodium urate precipitation. Struvite stones are caused by urinary tract infection with urease- producing microorganisms. Their treatment requires specific measures including complete surgical stone removal, short or long-term antibiotic treatment, to maintain urinary acidification to a pH below 6.2, and a urine volume of at least 2 litres/24 hours. L-methionine has been shown to effectively lower urine pH and the relative supersaturation of struvite. An essential aspect of medical management of urinary stone disease is treatment adherence, which depends on perceived benefit, treatment duration, and side effect profile. The side effects of citrate treatment are mild gastrointestinal disorders whereas thiazide diuretics tend to cause hypokalemia-related symptoms and less frequent metabolic and dermatologic side effects. Urease inhibitors for struvite stones and drugs used to enhance cystine solubility are more frequently associated with side effects. The use of smartphone applications can support patients by promoting adequate hydration, adherence to dietary recommendations, and compliance with prophylactic medication. Endoscopic techniques currently play a prevalent role in the removal of renal stones, while extracorporeal shock wave lithotripsy is today marginally used for specific indications. Different technical modalities can be used for percutaneous nephrolithotomy (PCNL), each with its own advantages and disadvntages (standard vs. mini, prone vs. supine, fluoroscopic vs ultrasound-guided). Flexible ureteroscopy or retrograde intrarenal renal surgery (RIRS) has extended its indications due to technological advancements in endoscopes and their accessories. The availability of new laser technologies (thulium fiber laser and pulse-modulated Ho:YAG laser) has enhanced stone fragmentation and dusting capabilities. However, their use exposes the renal parenchyma to high temperatures and pressures which could potentially contribute to renal damage. Factors influencing heat release include laser type and settings, exposure time, stone location, fiber-to-stone distance, irrigation volume and fluid circulation. Reduction of heat release can be achieved by limiting the laser settings to reasonable values or by improving fluid circulation with use of ureteral access sheaths, especially those navigable and equipped with suction. High intrarenal pressure is also closely associated with renal damage. Sustained high pressure or even pressure spikes may increase this risk, highlighting the importance of real-time pressure monitoring through sensors...

New suction endoscopes, ureteral access sheaths (UAS) and catheters aim to improve the efficacy of flexible ureteroscopy and optimize its safety. Suction UAS with non-flexible tips have shown promising results, especially in maintaining low intrarenal pressure, but also in removing small debris and reducing the “snow globe” effect. In addition, suctioning UAS with a flexible tip offers the advantage of being able to be navigated through the pyelocaliceal system to where the laser lithotripsy is performed. It can also remove small stone fragments when the flexible ureteroscope is retracted, using the Venturi effect. Direct in-scope suction (DISS) involves aspirating dust and small stone debris through the working channel of a flexible ureteroscope, thus regulating intrarenal pressure and improving visibility. Steerable aspiration catheters are other devices designed to increase stone clearance of the pyelocaliceal system. They are inserted under fluoroscopic guidance into every calyx after retraction of the flexible ureteroscope, alternating irrigation and aspiration to remove dust and small gravels. Combining flexible-tip suction UAS and the DISS technique may offer some advantages worth evaluating. The advantage of using these instruments to achieve a low intrarenal pressure was demonstrated. The true practical impact on the long-term stone-free status is a matter requiring further studies.