Faculty Bibliography

INTRODUCTION/BACKGROUND:The prevalence rate of upper urinary tract calculi in Saudi Arabia is one of the highest globally. Bilateral renal stone management is an option but is still controversial. METHODOLOGY/METHODS:The study was a retrospective study, including 31 patients with bilateral renal or ureteric stones who underwent bilateral same-session ureterorenoscopy (BSS-URS). The data collected included age, gender, body mass index (BMI), stone burden bilaterally, operative time bilaterally, hospital stay, stone location, type of anesthesia, stone history, renal anomaly as well as pre- and postoperative JJ stenting. In addition, data related to complications (ureteric injury, renal failure, urinary tract infection, pain requiring an emergency department visit within 1 week of the procedure), the stone-free rate (defined as £ 3 mm asymptomatic stone fragment identified with computed tomography Kidney, Ureter and Bladder 3 months after surgery was also collected. The data were collected from the electronic patient record system, entered in an Excel spreadsheet, and descriptive analysis was done. RESULTS:= 59) were stented postoperatively. CONCLUSION/CONCLUSIONS:BSS-URS is a safe and a highly effective management option for bilateral renal stones.

INTRODUCTION/BACKGROUND:Kidney stone disease is a common disease with high recurrence rates. Sufficient intake of water is the cornerstone in primary prevention of stone disease. However, the mineral composition of water can affect urinary minerals and influence stone formation. The aim of this study is to assess the variation in the mineral composition of bottled sparkling or carbonated drinking water across Europe. MATERIAL AND METHODS/METHODS:The two largest supermarket chains in each participating country were visited to obtain data on mineral composition regarding bicarbonate, calcium, magnesium, potassium, sodium and sulphates of sparkling or carbonated waters by reading the ingredient labels on the bottles supplied by the manufacturers. Alternatively, the web-shops of these supermarkets were consulted. RESULTS:In total, 126 sparkling water brands across ten European countries were analysed regarding mineral composition. The median concentrations per mineral varied greatly. The greatest variation in median mineral content was found for sodium and sulphates with levels ranging from 3.1 mg/l to 63.0 mg/l and 6.0 mg/l to 263.0 mg/l respectively. A wide distribution of calcium content was found in Switzerland, with calcium levels reaching up to 581.6 mg/l. CONCLUSIONS:This study confirms that the mineral composition of sparkling or carbonated water varies greatly across Europe. Patients with kidney stone disease should be aware that the mineral content of water may influence stone formation and be mindful of the great variation that exists between different water brands. Mineral water can be a source of potential promotors or inhibitors of stone formation and patients and urologists need to be mindful of this.

PURPOSE/OBJECTIVE:The aim of the current systematic review and meta-analysis is to provide an answer on which is the most appropriate approach for the management of the lower pole stones with a maximal dimension of 2 cm or less. MATERIALS AND METHODS/METHODS:A systematic review was conducted on PubMed®, SCOPUS®, Cochrane and EMBASE®. The PRISMA guidelines and the recommendations of the EAU Guidelines office were followed. Retrograde intrarenal surgery, shock wave lithotripsy and percutaneous nephrolithotomy were considered for comparison. The primary end point was the stone-free rate. RESULTS:A total of 15 randomized controlled trials were eligible. Percutaneous nephrolithotripsy and retrograde intrarenal surgery have higher stone-free rates in comparison to shock wave lithotripsy and require fewer re-treatment sessions. Operative time and complications seem to favor shock wave lithotripsy in comparison to percutaneous nephrolithotripsy, but this takes place at the expense of multiple shock wave lithotripsy sessions. Retrograde intrarenal surgery seems to be the most efficient approach for the management of stones up to 1 cm in the lower pole. CONCLUSIONS:The pooled analysis of the eligible studies showed that the management of lower pole stones should probably be percutaneous nephrolithotripsy or retrograde intrarenal surgery to achieve stone-free status over a short period and minimal number of sessions. For stones smaller than 10 mm, retrograde intrarenal surgery is more efficient in comparison to shock wave lithotripsy. The decision between the 2 approaches (percutaneous nephrolithotripsy or retrograde intrarenal surgery) should be individual, based on the anatomical parameters, the comorbidity and the preferences of each patient.

The objective is to establish whether a pattern of intestinal dysbiosis exists in calcium oxalate (CaOx) lithiasis and, if so, to identify its characteristics and explore whether there are differences in the pattern between CaOx dihydrate (COD) and monohydrate (COM) lithiasis. With this aim 24 patients diagnosed with CaOx lithiasis by means of optical microscopy and spectrometry were prospectively recruited. Faecal analysis was carried out by means of RT-PCR 16S rRNA assay and agar plate culture according to the methodology proposed by the Institute of Microecology (Herborn, Germany). The total number of bacteria was depleted due to COD lithiasis (p = 0.036). The mean values of immunoregulating microbiota were normal, but the percentage of normal values was lower in the COD group (30%) than in the COM group (69.2%) (p = 0.062). The total mean values of protective microbiota were normal in both groups. There was a large decrease in the mean values of the muconutritive microbiota Akkermansia muciniphila and Faecalibacterium prausnitzii, the most intense decline being observed in the COD group (p = 0.019). Levels of proteolytic microbiota were elevated in both groups, without differences between them. We conclude that patients with CaOx lithiasis have a chronic pro-inflammatory intestinal dysbiosis pattern characterised by a reduction in the total number of bacteria, a reduction in immunoregulating microbiota and a large reduction in muconutritive microbiota that is significantly more intense in COD lithiasis than in COM lithiasis.

BACKGROUND:Encrustation of ureteral double J stents is a common complication that may affect its removal. The aim of the proposed study is to evaluate the efficacy and safety of a new oral composition to prevent double J stent encrustation in indwelling times up to 8 weeks. METHODS:A double-blinded, multicenter, placebo-controlled trial was conducted with 105 patients with indwelling double J stents enrolled across 9 public hospitals in Spain. The patients were randomly assigned (1:1) into intervention (53 patients) or placebo (52 patients) groups for 3 to 8 weeks and both groups self-monitored daily their morning urine pH levels. The primary outcome of analysis was the degree of stent ends encrustation, defined by a 4-point score (0 - none; 3 - global encrustation) using macroscopic and electron microscopy analysis of crystals, after 3 to 8-w indwelling period. Score was exponentially transformed according to calcium levels. Secondary endpoints included urine pH decrease, stent removal, and incidence of adverse events. RESULTS:The intervention group benefits from a lower global encrustation rate of stent ends than placebo group (1% vs 8.2%; p < 0.018). Mean encrustation score was 85.12 (274.5) in the placebo group and 18.91 (102.27) in the intervention group (p < 0.025). Considering the secondary end points, treated patients reported greater urine pH decreases (p = 0.002). No differences in the incidence of adverse events were identified between the groups. CONCLUSIONS:Our data suggest that the use of this new oral composition is beneficial in the context of ureteral double J indwelling by decreasing mean, as well as global encrustation. TRIAL REGISTRATION/BACKGROUND:This trial was registered at www.clinicaltrials.gov under the name "Combined Use of a Medical Device and a Dietary Complement in Patient Urinary pH Control in Patients With an Implanted Double J Stent" with date 2nd November 2017, code NCT03343275, and URL.

OBJECTIVES:To investigate the diagnostic accuracy, inter-rater and intrarater agreement of grade predictions based on the visual appearance of papillary upper tract urothelial carcinoma (UTUC) during digital ureteroscopy. METHODS:Nine urologists predicted the histopathologic grade of 64 papillary UTUC (low-grade vs high-grade) by assessing the visual appearance of the tumors in videos from digital ureteroscopy. The diagnostic accuracy was estimated by comparing the grade predictions with the histopathology from colocalized biopsies. Inter-rater agreement was assessed by pairwise inter-rater percentage agreement and Fleiss Kappa analysis. The videos were rated in a random order again 30 days after the first assessment to evaluate the intrarater percentage agreement. RESULTS:Low-grade tumors were predicted correctly in 37%-85% of the cases with a median concordance of 59% for questionnaire 1 and 66% for questionnaire 2. High-grade tumors were predicted correctly in 26%-91% of the cases with a median concordance of 52% and 61% for each questionnaire. The median pairwise inter-rater percentage agreement was 66% for both questionnaires with a Fleiss Kappa of 0.29 and 0.38, respectively. The median intrarater percentage agreement was 81%. CONCLUSION:The histopathologic grade of UTUC is essential to the risk-stratification for treatment selection. Predictions of the histopathologic grade based on the visual appearance of papillary UTUC with digital ureteroscopy are often incorrect in comparison with biopsy results and yield low inter-rater agreement. Urologists must be aware of these limitations in the assessment of the tumor grade during digital ureteroscopy to warrant good clinical practice.

With an increase in the number of ureteroscopy (URS) procedures, URS is now performed more widely and is becoming a standard procedure for all urologists. There is also a rise in the complexity of these procedures and URS is now offered for treatment of stones as well as for diagnosis and treatment of urothelial tumours. We wanted to provide a 'pictorial review' of the 'tips and tricks' of URS, as the finer and technical details are often easier to understand and remember with images rather than through textual explanations.

PURPOSE/OBJECTIVE:To evaluate how variable working distances between the laser fiber and the stone influence ablation volume. METHODS:A laser fiber was fixed on a robotic arm perpendicular to an artificial stone. A single laser pulse was triggered at different working distances (0-2.0 mm in 0.2 mm increments) between the distal fiber tip and the stone. To achieve a measurable impact, pulse energy was set to 2 and 3 J, with either short or long pulse duration. Ablation volume was calculated with an optical microscope. Experiments were repeated five times for each setting. RESULTS:Highest ablation volume was observed with a long pulse of 3 J at a working distance of 0.4 mm between the laser fiber and the stone surface (p value < 0.05). At 2 J, the highest ablation volume was noticed with a short pulse in contact mode. However, ablation volume of the latter was not significantly greater than with a long pulse of 2 J at a working distance of 0.4 mm (p value > 0.05). Compared to lithotripsy in contact mode, triggering a single long pulse at 0.4 mm increased ablation volume by 81% (p value = 0.016) at 2 J and by 89% (p value = 0.034) at 3 J. CONCLUSIONS:For Ho:YAG laser lithotripsy, ablation volume may be higher in non-contact mode using long pulses, rather than in direct contact to the stone. Findings of the current study support the need of further studies of lithotripsy in non-contact mode.