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A 30-year-old woman presented with right-sided abdominal pain associated with fever. Her ultrasound showed right renal calculus with no hydronephrosis along with collection in peritoneal cavity and pouch of Douglas. CT showed ruptured right kidney with multiple renal and ureteric calculi as well as displaced renal calculi in perinephric space and pararenal space. Exploratory laparotomy and right nephroureterectomy were done. Nephrolithiasis with secondary infection makes the kidney fragile due to pathological changes, which may cause rupture of the renal calyces with trivial trauma or may be spontaneous. Distal obstruction by the stone and increased back pressure in the calyces may have added to the spontaneous rupture of the calyx and subsequently renal parenchyma. Management includes early exploration with nephrectomy and it is often life saving.

Context Paediatric stone disease is an important clinically entity and management is often challenging. Although it is known that the condition is endemic in some geographic regions of the world, the global incidence is also increasing. Patient age and sex; the number, size, location, and composition of the stone; and the anatomy of the urinary tract are factors that need to be taken into consideration when choosing a treatment modality. Objective To provide a general insight into the evaluation and management of urolithiasis in the paediatric population in the era of minimally invasive surgery. Evidence acquisition A nonsystematic review of the literature on management of paediatric urolithiasis was conducted with the aim of presenting the most suitable treatment modality for different scenarios. Evidence synthesis Because of high recurrence rates, open surgical intervention is not the first option for paediatric stone disease, except for very young patients with very large stones in association with congenital abnormalities. Minimally invasive surgeries have become the first option with the availability of appropriately sized instruments and accumulating experience. Extracorporeal shockwave lithotripsy (SWL) is noninvasive and can be carried out as an outpatient procedure under sedation, and is the initial choice for management of smaller stones. However, for larger stones, SWL has lower stone-free rates and higher retreatment rates, so minimally invasive endourology procedures such as percutaneous nephrolithotomy and retrograde intrarenal surgery are preferred treatment options. Conclusions Contemporary surgical treatment for paediatric urolithiasis typically uses minimally invasive modalities. Open surgery is very rarely indicated. Patient summary Cases of urinary stones in children are increasing. Minimally invasive surgery can achieve high stone-free rates with low complication rates. After stone removal, metabolic evaluation is strongly recommended so that medical treatment for any underlying metabolic abnormality can be given. Regular follow-up with imaging such as ultrasound is required because of the high recurrence rates.

Context Although percutaneous nephrolithotomy (PCNL) has been performed for decades and has gone through many refinements, there are still concerns regarding its more widespread utilization because of the long learning curve and the potential risk of severe complications. Many technical details are not included in the guidelines because of their nature and research protocol. Objective To achieve an expert consensus viewpoint on PCNL indications, preoperative patient preparation, surgical strategy, management and prevention of severe complications, postoperative management, and follow-up. Evidence acquisition An international panel of experts from the Urolithiasis Section of the European Association of Urology, International Alliance of Urolithiasis, and other urology associations was enrolled, and a prospectively conducted study, incorporating literature review, discussion on research gaps (RGs), and questionnaires and following data analysis, was performed to reach a consensus on PCNL. Evidence synthesis The expert panel consisted of 36 specialists in PCNL from 20 countries all around the world. A consensus on PCNL was developed. The expert panel was not as large as expected, and the discussion on RGs did not bring in more supportive evidence in the present consensus. Conclusions Adequate preoperative preparation, especially elimination of urinary tract infection prior to PCNL, accurate puncture with guidance of fluoroscopy and/or ultrasonography or a combination, keeping a low intrarenal pressure, and shortening of operation time during PCNL are important technical requirements to ensure safety and efficiency in PCNL. Patient summary Percutaneous nephrolithotomy (PCNL) has been a well-established procedure for the management of upper urinary tract stones. However, according to an expert panel consensus, core technical aspects, as well as the urologist’s experience, are critical to the safety and effectiveness of PCNL.

PURPOSE: To evaluate efficacy and safety of flexible ureteroscopy and laser lithotripsy (FURSL) for treatment of the upper urinary tract calculi. METHODS: We retrospectively analyzed 784 patients who underwent FURSL between January 2015 and October 2020 in our unit. All patients were preoperatively evaluated with urine analysis, serum biochemistry, urinary ultrasonography, non-contrast computed tomography and intravenous urography. The procedure was considered as successful in patients with complete stone disappearance or fragments

Objective To determine whether 24-hour urine testing in Veterans with USD (urinary stone disease) reduces or delays urinary stone recurrence. Methods Cohort study of national health record data from Veterans Health Administration from 2007 through 2013. We utilized a study population of 130,129 Veterans with USD based on diagnostic or procedural codes and excluded those with USD claims in the 2 years before cohort entry. We then created a propensity-score matched cohort of 14,854 Veterans based on completion of 24-hour urine testing within 6 months of stone diagnosis. Primary outcome was time-to-next clinically significant stone event, defined as an emergency department visit, inpatient admission related to a urinary stone, or urologic stone procedure with 5-year follow up. Results Of 14,854 Veterans in the propensity-score matched cohort, 8560 (57.6%) experienced a recurrent USD event. Completion of 24-hour urine testing was associated with a higher risk of developing a second stone event (hazard ratio [HR] 1.17, 95% confidence interval [95% CI] 1.12-1.22). Among Veterans with known recurrent disease, we examined time to a third stone event. In this cohort of 4736 patients, completion of 24-hour urine testing was not associated with a higher risk of developing a third stone event (HR 1.06, 95% CI 0.99-1.12). Conclusion Completion of 24-hour urine testing was not associated with a reduction in urinary stone recurrence. These findings challenge the validity of a longstanding recommendation in general medicine, nephrology, and urology practice.

Objective: To determine the risk of postpartum urinary stone disease in women with a history of stone disease during pregnancy. Methods: Using the Optum® de-identified Clinformatics® Datamart we identified pregnant women with urinary stone disease in the United States between January 2003 to December 2017 by standardized International Classification of Diseases Ninth and Tenth Editions (ICD-9 and ICD-10), and Current Procedural Terminology code criteria. We limited the cohort to include women without evidence of urinary stone disease before pregnancy. We abstracted patient demographic characteristics, clinical risk factors for stone disease, and data for urinary stone disease encounters and related procedures after pregnancy. Encounters occurring within 1 year of pregnancy were excluded. Cox proportional hazard models were used to analyze for significance. Results: We identified a total of 1,395,783 pregnant women with a median postpartum follow-up of 4.0 years, including 5971 (0.4%) women with a urinary stone during pregnancy. Of these, 736 (12.3%) had an additional urinary stone diagnosis claim after pregnancy, compared with 13,275 (0.95%) women without a history of stone disease during pregnancy (p

Background Urolithiasis in small ruminants has a poor long‐term prognosis, and long‐term clinical outcomes are variable and unpredictable. Objectives To assess the accuracy of preoperative and postoperative blood l‐lactate concentrations in predicting a negative outcome in goats undergoing tube cystostomy. Animals Thirty‐four male goats undergoing tube cystostomy. Methods Retrospective study. Medical records of goats undergoing tube cystostomy from 2015 to 2020 were reviewed. Clinical variables recorded included signalment, procedures before surgery, urolith location and type, duration of hospitalization, and heart rate. PCV, plasma total protein, potassium, preoperative and postoperative blood l‐lactate concentrations, preoperative and postoperative creatinine concentrations, and relative changes in blood l‐lactate and creatinine concentrations over time were measured using heparinized blood. A negative outcome was defined as death or euthanasia from urolithiasis complications at 6 months after discharge. Negative outcomes as a function of independent clinical variables were evaluated using χ2 or Fisher's exact tests, and multivariate logistic regression. P .05). Conclusions and Clinical Importance Veterinarians should advise clients that clinical outcomes after tube cystostomy in goats are likely unpredictable.

Background Self-care and participation of patients in improving health and increasing awareness about the risk factors that affect the development of disease in patients with urinary tract stones are influential factors in controlling and improving the quality of life in these patients. In this regard, the availability and capability of smartphones increase patients’ self-care ability. The present study aimed to develop and evaluate a self-care application based on smartphones for patients with urinary tract stones. Methods The present study is a developmental and applied study that was conducted in three phases. First, the information needs and functionalities of the self-care application were determined by surveying 101 patients, 32 urologists and nephrologists, 11 nurses, and six other specialists. In the second phase, the initial sample of the smartphone-based application was created, and in the third phase, the designed application was evaluated by 15 experts using the standard Post-Study System Usability Questionnaire (PSSUQ 18.3) and Nielsen’s Attributes of Usability (NAU) questionnaire. Results of the questionnaires were entered into SPSS-23 software for analysis using descriptive statistics. Results In the first phase, 21 information elements and nine critical functionalities for the self-care application were identified, and then this application was designed by Java programming language. The evaluation of experts showed that two aspects of the quality of system user interface from the user's point of view and the overall performance of the application together obtained the highest score (6.43 from 7), which was equal to 91.85%. Then according to the experts, aspects of the degree of convenience and user-friendliness of the application received the highest score (6.10 from 7), which was equal to 87.14%, and also all aspects of the application were evaluated at an acceptable level. In general, results of the evaluation of application's usability by experts showed that the usability of the application for patients with urinary tract stones was at an acceptable level. Conclusion According to the results obtained from evaluating the smartphone-based application for patients with urinary tract stones, this self-care application can be used to prevent and control urinary tract stones and facilitate self-care and active patient participation in care.

Objective. To investigate the efficacy and safety of the oblique supine lithotomy during percutaneous nephrolithotomy (PCNL) to treat upper urinary calculi. Methods. Clinical data were retrospectively analyzed for 371 patients with upper urinary calculi who underwent PCNL at The First Affiliated Hospital of Guangzhou University of Chinese Medicine from January 2017 to October 2020. Based on different positions, patients were divided into the observation group (oblique supine lithotomy position, 155 cases, Group 1) or control group (prone position, 216 cases, Group 2). Groups were compared for effectiveness, complications, bleeding, surgical time, clinical indicators, and hospitalization time. Results. There were no significant differences in the clinical baseline data between the two groups ( p > .05). However, the stone-free rate for patients was significantly higher in the observation than in the control group ( p < .05). Both operation time and hospital stay time were significantly lower in the observation versus the control groups ( p < .05). No significant differences were observed for complications or amount of blood loss ( p > .05). Conclusion. In patients with upper urinary calculi, percutaneous nephrolithotomy in the oblique supine lithotomy position has a higher stone-free rate than the prone position. This approach can shorten the operation and provide better comfort and quicker recovery to the patients. A further advantage is that there is no difference in safety and blood loss between the prone position and the oblique lithotomy position.

Hypouricemia in kidney transplant (KT) recipients is rare since they usually have subnormal kidney function which raises serum uric acid level. Recently, interests in pathogenesis of hypouricemia have been increasing due to the understanding of the role of uric acid transporter in renal hypouricemia (RHUC). We herein report the case of RHUC consequently developed in a KT recipient from a living donor with RHUC diagnosed by the detailed urinary and genetic test. A 73-year-old Japanese man underwent KT, and the donor was his wife who had hypouricemia [serum uric acid (S-UA) 0.6 mg/dL]. Nine months after KT, the recipient’s S-UA was low (1.5 mg/dL) with serum creatinine (S-Cr) of 1.56 mg/dL, and fractional excretion of UA (FEUA) was high (59.7%; normal

Objective This paper presents the differential diagnosis of a calcified mass found in the pelvic cavity of an adult male dating to the 10th century AD. Materials Skeletal remains of an adult male exhumed from the cemetery associated with the early medieval church of Riner (Solsones, Catalonia). Methods The structure and composition of the mass were examined by x-ray imaging, microscopic stereoscopy and Fourier transform infrared spectrometry analysis. Results The examination reveals a light brown kidney-shaped calcification with well-defined margins, irregular hypodense zones, and several thin concentric layers. The obtained spectra showed a mixture of carbonate apatite (with a high level of carbonation) and calcite in all the sections studied. Conclusion The calcification most likely corresponds to a urinary calculus of infectious origin. Significance Given the insights that urinary calculi can provide towards understanding consequences of infection and environmental conditions, this case will be of interest to other researchers wishing to initiate comparative analyses. Limitations The discussion of the etiology of the stone is limited by the lack of preservation of certain elements such as struvite.

Background Acute renal colic caused by urinary calculi (ARCUC) has a considerable impact on the quality of life. Acupuncture might be a potential treatment option. However, the evidence is limited. We will conduct this trial to evaluate the efficacy and safety of acupuncture as adjunctive treatment to diclofenac for ARCUC. Methods/design A total of 80 eligible patients who are diagnosed with urinary stone renal colic will be randomly allocated to the acupuncture group or the sham acupuncture group. Each patient will receive 1 session of acupuncture or sham acupuncture. The primary outcome will be the response rate of patients achieving a reduction of > 50% on visual analog score (VAS) from baseline to 10 min after treatment. Secondary outcomes will include the VAS, remedial analgesia, re-visit and admission rate, blinding assessment, credibility and expectancy, and adverse event. All patients who receive randomization will be included in the intent-to-treat analysis. Discussion The finding of this trial will provide evidence on the efficacy and safety of acupuncture for the treatment of ARCUC. The results of this study will be published in peer-reviewed journals. Trial registration ClinicalTrials.gov ChiCTR 1900025202. Registered on August 16, 2019.

Adhesion molecules play an important role in urinary calculus formation. The expressions of adhesion molecules in renal tubular has been reported in some animals. However, the role of adhesion molecules in the process of sheep urinary calculus formation is still unclear. The magnesium ammonium phosphate (MAP) is the main component of sheep urinary calculus. In this paper, the sheep renal tubular epithelial cells (RTECs) were isolated and treated with MAP, the expressions of osteopontin (OPN), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and apoptosis-related indicators caspase-3, Bcl-2 and Bax in RTECs were observed, the viability of RTECs was detected by Cell Counting Kit-8 (CCK-8). The levels of superoxide dismutase (SOD) and malondialdehyde (MDA), and the expressions of inflammatory factors Interleukin-6 (IL-6), Interleukin-1 (IL-1), Interleukin-17 (IL-17) and tumor necrosis factor-α (TNF-α) were measured by enzyme-linked immunosorbent (ELISA). The histopathological observation of kidney in urolithiasis sheep was made. The results showed that MAP could reduce the viability and SOD activity, enhance the activity of MDA significantly and promote the expressions of IL-1, IL-6, IL-17 and TNF-α of RTECs. By western blot and qPCR methods, the expressions of ICAM-1, VCAM-1 and OPN increased in 48 h. In addition, the expression of caspase-3 increased significantly and the ratio of Bcl-2/Bax reduced with exposure to MAP. The renal tissue structure was seriously damaged, the RTECs in urolithiasis sheep were degenerative and necrotic.

Background Patients with urolithiasis undergo radiation overexposure from computed tomography (CT) scans. Improvement of image reconstruction is necessary for radiation dose reduction. Purpose To evaluate a deep learning-based reconstruction algorithm for CT (DLIR) in the detection of urolithiasis at low-dose non-enhanced abdominopelvic CT. Material and Methods A total of 75 patients who underwent low-dose abdominopelvic CT for urolithiasis were retrospectively included. Each examination included three reconstructions: DLIR; filtered back projection (FBP); and hybrid iterative reconstruction (IR; ASiR-V 70%). Image quality was subjectively and objectively assessed using attenuation and noise measurements in order to calculate the signal-to-noise ratio (SNR), absolute contrast, and contrast-to-noise ratio (CNR). Attenuation of the largest stones were also compared. Detectability of urinary stones was assessed by two observers. Results Image noise was significantly reduced with DLIR: 7.2 versus 17 and 22 for ASiR-V 70% and FBP, respectively. Similarly, SNR and CNR were also higher compared to the standard reconstructions. When the structures had close attenuation values, contrast was lower with DLIR compared to ASiR-V. Attenuation of stones was also lowered in the DLIR series. Subjective image quality was significantly higher with DLIR. The detectability of all stones and stones >3 mm was excellent with DLIR for the two observers (intraclass correlation [ICC] = 0.93 vs. 0.96 and 0.95 vs. 0.99). For smaller stones (Conclusion For low-dose abdominopelvic CT, DLIR reconstruction exhibited image quality superior to ASiR-V and FBP as well as an excellent detection of urinary stones.

Objectives Up to 0.3% of Japanese have hypouricaemia. Most cases appear to result from a hereditary disease, renal hypouricaemia (RHUC), which causes exercise-induced acute kidney injury and urolithiasis. However, to what extent RHUC accounts for hypouricaemia is not known. We therefore investigated its frequency and evaluated its risks by genotyping a general Japanese population. Methods A cohort of 4993 Japanese was examined by genotyping the non-functional variants R90H (rs121907896) and W258X (rs121907892) of URAT1/SLC22A12, the two most common causative variants of RHUC in Japanese. Results Participants’ fractional excretion of uric acid and risk allele frequencies markedly increased at lower serum uric acid (SUA) levels. Ten participants (0.200%) had an SUA level ≤2.0 mg/dl and nine had R90H or W258X and were likely to have RHUC. Logistic regression analysis revealed these URAT1 variants to be significantly and independently associated with the risk of hypouricaemia and mild hypouricaemia (SUA ≤3.0 mg/dl) as well as sex, age and BMI, but these URAT1 variants were the only risks in the hypouricaemia population (SUA ≤2.0 mg/dl). W258X was only a risk in males with SUA ≤3.0 mg/dl. Conclusion Our study accurately reveals the prevalence of RHUC and provides genetic evidence for its definition (SUA ≤2.0 mg/dl). We also show that individuals with SUA ≤3.0 mg/dl, especially males, are prone to RHUC. Our findings will help to promote a better epidemiological understanding of RHUC as well as more accurate diagnosis, especially in males with mild hypouricaemia.

Percutaneous nephrostomy (PCNL) and retrograde intrarenal surgery (RIRS) are the two main treatments for upper urinary tract stones. The aim of our study was to compare the effectiveness and safety of standard PCNL (S-PCNL) and RIRS for the treatment of stones at ureteropelvic junction with high-grade hydronephrosis. The study included 118 patients who underwent surgery for stones at ureteropelvic junction. S-PCNL and RIRS were performed on 66 and 52 patients, respectively. Patient age, sex, body mass index (BMI), stone side, history of urinary tract infection (UTI), history of diabetes, history of ESWL, stone size, Hounsfield unit (HU) values of stones, grade of hydronephrosis, operating time, postoperative hemoglobin loss, narcotic analgesic use, postoperative transfusion rates, stone-free rates (SFRs), length of hospital stay, complication rates and number of secondary interventions were recorded. The comparison of the operative data between the two groups revealed no statistically significant differences in the operative time, SFRs, narcotic analgesic use, postoperative transfusion rate or other postoperative complications defined according to the Clavien system (P > 0.05). The postoperative urinary sepsis rate in the RIRS group was as high as 15.4%, which was much higher than the 1.5% rate observed in the S-PCNL group, and the difference was statistically significant (P

© 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.We evaluated the demographic features, etiologic risk factors, treatment strategies, and outcome of the infants and children with urolithiasis (UL). A retrospective multicenter study was conducted including 23 Pediatric Nephrology centers in Turkey. The medical records of 2513 children with UL were reviewed. One thousand, three hundred and four boys and 1209 girls (1.1:1) were reported. The mean age at diagnosis was 39.5 ± 35 months (0.4–231 months), and 1262 patients (50.2%) were in the first year of life (infants). Most of the cases with infantile UL were diagnosed incidentally. Microlithiasis (< 3 mm) was found in 794 patients (31.6%), and 64.5% of the patients with microlithiasis were infants. Stones were located in the pelvis-calyces in 63.2% (n: 1530) of the cases. The most common stone type was calcium oxalate (64.6%). Hypocitraturia was the most common metabolic risk factor (MRF) in children older than 12 months, but in infancy, hypercalciuria was more common. Fifty-five percent of the patients had received at least one medical treatment, mostly potassium citrate. At the end of a year’s follow-up, most of the patients with microlithiasis (85%) showed spontaneous remission. The rate of spontaneous stone resolution in infants was higher than in children. Spontaneous remission rate was higher in cases with MRF (− ) stones than in MRF (+) stones. However, remission rate with medical treatment was higher in cases with MRF (+) stones. This study represents the results of a large series of infants and children with UL and showed that there are several differences such as underlying metabolic and anatomic abnormalities, clinical course, and stone remission rates between infants and children with urinary stone disease.

The efficacy and safety of super-mini percutaneous nephrolithotomy (SMP, 14 Fr) was compared with mini percutaneous nephrolithotomy (MPCNL, 16 Fr) for the treatment of upper urinary tract stones in children (

Background Double J (DJ) ureteral stents are commonly inserted after ureteroscopy (URS) procedures for stone treatment. However, stent-related symptoms are still a major issue. Objective To determine whether a commercially available pigtail suture stent (PSS) can reduce stent-related symptoms compared to a conventional DJ stent after uncomplicated URS. Design, setting, and participants We designed a randomized, single-blind, parallel-group trial from January to November 2020. The inclusion criteria were stone-free URS without intraprocedural complications. Patients with distal ureteral stones were excluded. Intervention Insertion of a PSS or DJ stent after URS. Outcome measurements and statistical analysis The primary endpoint was the Urinary Symptom Index score on the Ureteral Stent Symptoms Questionnaire (USSQ) 2 wk after URS. Secondary endpoints were USSQ domain scores and responses to individual USSQ questions at 2 d and 2 wk after surgery. Results and limitations A total of 78 patients were randomized and treated according to protocol. The Urinary Symptom Index score (p = 0.004), overall Visual Analogue Scale (VAS) score (p = 0.022), and the percentage of patients complaining of pain (63.9% vs 86.1%, p = 0.029) were significantly in favor of PSS at both 2 d and 2 wk after URS. At 2 d, the VAS score among patients with pain (p = 0.025) and the General Health Index score (p = 0.036) were significantly better in the PSS group. No severe complications occurred in either group. Study limitations are the exclusion of patients with distal ureteral stones and the limited sample size. Conclusions PSS significantly reduced stent-related symptoms after URS, in particular urinary symptoms and pain, compared to conventional DJ stents, and showed a good safety profile. Patient summary Stents are hollow tubes placed in the passage between the kidney and the bladder (ureter). The standard stent has two coiled ends (double J stent) to keep it in place in both the kidney and the bladder. We tested a commercial stent with two strings at the bladder end (pigtail suture stent) after procedures to remove stones from the upper urinary tract and found that it caused less stent-related symptoms compared to a double J stent. This trial is registered at Clinicaltrials.gov as NCT03344120., Take Home Message A pigtail suture stent significantly reduced stent-related symptoms compared to a conventional double J stent, in particular urinary symptoms and pain. We suggest the use of a pigtail suture stent rather than a double J stent after uncomplicated ureteroscopy performed for renal or proximal to mid-ureteral stones.

Author(s): Kopecny, Lucy; Palm, Carrie A; Segev, Gilad; Westropp, Jodi L | Abstract: BackgroundUrolithiasis is a common and often recurrent problem in dogs.ObjectiveTo evaluate trends in urolith composition in dogs and to assess risk factors for urolithiasis, including age, breed, sex, neuter status, urolith location, and bacterial urolith cultures.Sample populationA total of 10 444 uroliths and the dogs from which they were obtained.MethodsThe laboratory database at the UC Davis Gerald V. Ling Urinary Stone Analysis Laboratory was searched for all urolith submissions from dogs between January 2006 and December 2018. Mineral type, age, breed, sex, neuter status, urolith location, and urolith culture were recorded. Trends were evaluated and variables compared to evaluate risk factors.ResultsCalcium oxalate (CaOx) and struvite-containing uroliths comprised the majority of all submissions from dogs, representing 47.0% and 43.6%, respectively. The proportion of CaOx-containing uroliths significantly decreased from 49.5% in 2006 to 41.8% in 2018 (P = .006), with no change in the proportion of struvite-containing urolith submissions. Cystine-containing uroliths comprised 2.7% of all submissions between 2006 and 2018 and a significant nonlinear increase in this mineral type occurred over time (1.4% of all submissions in 2006 to 8.7% in 2018; P l .001). Of all cystine-containing uroliths, 70.3% were from intact male dogs. Age, breed, and sex predispositions for uroliths were similar to those previously identified.Conclusions and clinical importanceAlthough calcium oxalate- and struvite-containing uroliths continue to be the most common uroliths submitted from dogs, a decrease in the proportion of CaOx-containing uroliths and an increase in the proportion of cystine-containing uroliths occurred during the time period evaluated.

Introduction: The current study evaluated the efficacy and safety of external physical vibration lithecbole (EPVL) after extracorporeal shock wave lithotripsy (SWL) or retrograde intrarenal surgery...

Purpose: To test the effectiveness (Participant A) and tolerability (Participant B) of urinary stone comminution in the first-in-human trial of a new technology, burst-wave lithotripsy (BWL). Materials and Methods: An investigational BWL and ultrasonic propulsion system was used to target a 7-mm kidney stone in the operating room before ureteroscopy (Participant A). The same system was used to target a 7.5 mm ureterovesical junction stone in clinic without anesthesia (Participant B). Results: For Participant A, a ureteroscope inserted after 9 minutes of BWL observed fragmentation of the stone to

The purpose of this study in a small group of non-stone-forming Chinese persons was to measure the levels of supersaturation with calcium oxalate and calcium phosphate and pH with the aim of confirming if any of the different short-term urine samples were better for risk evaluation than a 24-h sample. Nine normal men and 1 woman collected urine during 4 periods of the day. Period 1 between 08 and 12 h, Period 2 between 12 and 18 h, Period 3 between 18 and 22 h, and Period 4 between 22 and 08 h. Each sample was analysed for calcium, oxalate, citrate, magnesium and phosphate, and estimates of supersaturation with calcium oxalate (CaOx) and calcium phosphate (CaP) were expressed in terms of AP(CaOx) and AP(CaP) index. An estimate of the solute load of CaOx was also calculated. Urine composition for 24-h urine (Period 24) was obtained mathematically from the analysed variables. Urine composition corresponding to 14-h urine portions 22–12 h (Period 14N) and 08–22 h (Period 14 D) were calculated. The lowest pH levels were recorded in Period 1 urine. The highest level of AP(CaOx) index was recorded during Period 1, and the product AP(CaOx) index × 107 × hydrogen ion concentration was significantly higher in Period 1 urine than in 24-h urine (p = 0.02). Also, the product SL(CaOx) × 107 × hydrogen ion concentration was significantly higher in Period 1 urine (p = 0.02). Low AP (CaP) index levels were recorded in Period 4, but also in all periods following dietary loads of calcium and phosphate. With the important reservation that the analytical results were obtained from non-stone-forming persons, the conclusion is that analysis of urine samples collected between 08 and 12 h might be an alternative to 24-h urine. The risk evaluation might advantageously be expressed either in terms of the product AP(CaOx) index × 107 × hydrogen ion concentration or the product SL(CaOx) × 107 × hydrogen ion concentration.

Background: Steinstrasse, is described as array of stone pieces in the ureter following extracorporeal shock wave lithotripsy (SWL). It is well-recognized, transient event. Steinstrasse clears spontaneously, however about 6% require intervention. Spontaneous steinstrasse without prior history of SWL is a rare occurrence and only few case reports are published in literature. Objective of the study was to assess the aetiology and management issues of large spontaneous steinstrasse in our centre. Method: From February 2017 to March 2019, 684 patients underwent SWL for renal or ureteric stones. Twenty-eight patients presented with steinstrasse of which nine patients had no prior history of SWL. Detailed clinical profile and management issues have been discussed. Result: Among the nine patients of spontaneous steinstrasse, there were six males and three females. Mean age of the patients was 39 years (±13 years SD). Bilateral large spontaneous steinstrasse was seen in one out of nine patients. Seven patients had associated renal stones. Five patients presented with obstructive uropathy and three out of them had urosepsis as initial presentation. Ureterolithotomy and percutaneous nephrolithotomy were commonly performed procedures for stone clearance. Metabolic work was done in all cases in follow up period. Three patients had hypercalciuria and hypocitraturia suggestive of renal tubular acidosis. Conclusion: Large spontaneous steinstrasse is uncommon case scenario. It can be subtle in presentation and yet have significant patient consequence in terms of renal function and infection. Prompt management is essential to preclude permanent loss of renal function. Metabolic evaluation is indispensable in such cases.

Background Virtual unenhanced (VUE) images obtained by using a dual-energy CT (DECT) multimaterial decomposition algorithm hold promise for diagnostic use in the abdomen in lieu of true unenhanced (TUE) images. Purpose To assess VUE images obtained from a DECT multimaterial decomposition algorithm in patients undergoing renal mass and urinary stone evaluation. Materials and Methods In this retrospective Health Insurance Portability and Accountability Act-compliant study, DECT was performed in patients undergoing evaluation for renal mass or urinary stone. VUE images were compared quantitatively to TUE images and qualitatively assessed by four independent radiologists. Differences in attenuation between VUE and TUE images were summarized by using 95% limits of agreement. Diagnostic performance in urinary stone detection was summarized by using area under the receiver operating characteristic curve, sensitivity, and specificity. Results A total of 221 patients (mean age ± standard deviation, 61 years ± 14; 129 men) with 273 renal masses were evaluated. Differences in renal mass attenuation between VUE and TUE images were within 3 HU for both enhancing masses (95% limits of agreement, -3.1 HU to 2.7 HU) and nonenhancing cysts (95% limits of agreement, -2.9 HU to 2.5 HU). Renal mass classification as enhancing mass versus nonenhancing cyst did not change (reclassification rate of enhancing masses, 0% [0 of 78]; 95% CI: 0, 5; reclassification rate of nonenhancing cysts, 0% [0 of 193]; 95% CI: 0, 2) with use of VUE in lieu of TUE images. Among 166 urinary stones evaluated, diagnostic performance of VUE images for stone detection was lower compared with that of TUE images (area under the receiver operating characteristic curve, 0.79 [95% CI: 0.73, 0.84] vs 0.93 [95% CI: 0.91, 0.95]; P < .001) due to reduced sensitivity of VUE for detection of stones 3 mm in diameter or less compared with those greater than 3 mm (sensitivity, 23% [25 of 108; 95% CI: 12, 40] vs 88% [126 of 144; 95% CI: 77, 94]; P < .001). Conclusion Compared with true unenhanced images, virtual unenhanced (VUE) images were unlikely to change renal mass classification as enhancing mass versus nonenhancing cyst. Diagnostic performance of VUE images remained suboptimal for urinary stone detection due to subtraction of stones 3 mm or less in diameter. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Sosna in this issue.

Objective:The aim of this study is to determine the relationship between each of the three dimensions of a ureteric stone and the passage rate and to identify ureteric stones with an oval/elongated shape and determine whether the stone passage rate was most closely related to any of the three stone dimensions.Materials and Methods:A retrospective study of all patients who had a computed tomography scan with renal colic protocol at our hospital between January 1, 2016 and June 30, 2017. The maximum axial diameter, axial width, maximum coronal length and location of all stones were recorded. Patients were followed up for at least six months to ensure that the stones had been expelled or surgically removed.Results:Ninety patients spontaneously passed their ureteric calculus, and 80 patients received surgery in this study. If the patients who received surgery within three days of diagnosis were excluded, the spontaneous stone passage rate was 81.1%. Of the 90 patients with spontaneous stone passage, 38.9%, 15.6% and 6.7% patients had stones with at least a 1.0, 1.5 and 2.0 mm difference between the maximum axial and coronal dimensions, respectively. Within the subset of calculi that passed within 90 days, these elongated calculi required between 3 and 6 less median days to pass than the more rounded calculi, although this was not statistically significant.Conclusion:This study showed that in isolation, the individual dimension of a ureteric calculus did not significantly affect the time required to pass the calculus spontaneously. Elongated-shaped calculi were not common in this study.

Background The COVID-19 pandemic has seen a change in the numbers of patients presenting to the emergency department (ED) with non-COVID symptoms, resulting in delayed presentations of many medical and surgical conditions. Aims To examine the impact of COVID-19 on acute urolithiasis presentations to the ED. Methods In this retrospective, single-centre, observational study, we reviewed all CT KUBs (and their corresponding cases) ordered in ED for possible acute urolithiasis in a 100-day period immediately prior to COVID-19 and in a 100-day period immediately afterwards. We sought to establish the number of CT KUBs performed and the number confirming urolithiasis. We recorded patients’ age, gender, stone size and location. We also analysed CRP, WCC and creatinine as well as the duration of patients’ pain and the management strategy adopted for each case. Results One hundred ninety-eight CT KUBs were performed, 94 pre-COVID and 104 intra-COVID. A total of 70.2% (n = 66) and 66.3% (n = 69) were positive for urolithiasis pre-COVID and intra-COVID respectively (p = 0.56). There was a significantly higher percentage of females pre-COVID compared with intra-COVID (54% vs 36%, p = 0.012). There was no difference in median ureteric stone size seen between the groups (4.7 mm pre-COVID vs 4.0 mm intra-COVID, p = 0.179). There were no significant differences in WCC, CRP or creatinine levels. One patient in the pre-COVID group and two in the intra-COVID groups required percutaneous nephrostomies. Conclusion The COVID-19 pandemic did not result in fewer or sicker patients presenting with acute ureteric colic cases to the ED.

Purpose Basal metabolic rate (BMR) is an indicator of overall body metabolism and may portend unique aberrations in urine physico-chemistry and stone recurrence. The present study examined the effect of predicted BMR on 24 hours urinary metabolic profiles and stone recurrence in obese stone patients. Materials and Methods Data from 308 obese patients (body mass index [BMI] ≥30 kg/m2) diagnosed with urinary stone disease between 2003 and 2015 were analyzed retrospectively. BMR was calculated using the Harris–Benedict equation, and patients were classified into two predicted BMR categories (, Graphical Abstract

To analyze various compositions of urinary stones using revolution spectral CT (rapid kV switching dual-energy CT) in vivo. 202 patients with urinary stones underwent spectral CT before surgery. Zeff peak, overall scope and CT values were detected. Moreover, water/iodine attenuating material images were obtained. Removed stones were subjected to infrared spectroscopy after surgery. The results of infrared spectroscopy were compared with CT. 28 stones (14.08%) with single composition, 165 stones with two mixed compositions (81.68%), and 9 stones with three mixed compositions (4.46%) were observed. When Zeff peaks of stones with single/mixed compositions were summarized together, 146 peaks of calcium oxalate monohydrate, 119 peaks of calcium oxalate dihydrate, 55 peaks of carbapatite, 38 peaks of urate, 16 peaks of struvite, and 11 peaks of brushite were totally observed. 93.8% of calcium oxalate monohydrate had Zeff peaks between 13.3 and 14.0. 91.6% of calcium oxalate dihydrate had peaks between 12.0 and 13.3. For carbapatite, 90.9% of stones had peaks from 14.0 to 15.0. A total of 94.8% of urate had peaks between 7.0 and 11.0. 93.8% of struvite had peaks between 11.0 and 13.0, and 90.9% of brushite had peaks between 12.0 and 14.0. Moreover, densities of urate, struvite and brushite were low density in iodine-based images and high-density in water-based images. The in-vivo analysis of spectral CT in urinary stone revealed characteristics of different compositions, especially mixed compositions. An in-vivo predictive model may be constructed to distinguish stone compositions.

Introduction: Patients nowadays often search video-sharing platforms for online patient education materials. Since previous assessments of urological videos were limited to English, we systematically assessed the quality of videos on treatment of benign prostatic hyperplasia (BPH), prostate cancer (PCa), and urinary stone disease (USD) in 4 different languages on YouTube using validated instruments. Methods: The search for videos on YouTube addressing treatment options of BPH, PCa, and USD was performed in October 2020 in ­English, French, German, and Italian. Assessed parameters included basic data (e.g., number of views), grade of misinformation, and reporting of conflicts of interest. Quality of content was analyzed using the validated DISCERN questionnaire. Data were analyzed using descriptive statistics. Results: A total of 240 videos (60 videos in each language) were analyzed. Videos on USD in English had the highest number of views (median views 271,878 [65,313–2,513,007]). The median overall quality of videos assessed showed a moderate quality (2.5–3.4 points out of 5 points for DISCERN item 16). Median total DISCERN score of all videos divided by language showed very similar results: English (39.75 points), French (38 points), German (39.5 points), and Italian (39 points). Comparing the different diseases, videos about BPH showed the highest median scores, especially in German language (median score 43.25 points). Conclusions: Videos concerning the treatment of BPH, PCa, and USD have a low to moderate quality of content, with no differences seen between the languages assessed. These findings further support the notion of improved patient information materials on video platforms such as YouTube.

Most human urinary stones are calcium-based and are often associated with hypercalciuria. A simple test described in 1975 by Pak et al allows for pathogenic classification of hypercalciuria: the calcium load test (CLT). The CLT explores calcium homeostasis after a low-calcium diet and then a calcium load (typically oral administration of 1 g of elemental calcium). Only simple laboratory equipment is required. Inadequate calcium excretion after a calcium-free diet or a calcium load is suggestive of resorptive or absorptive hypercalciuria, respectively. The CLT is particularly valuable in diagnosing primary hyperparathyroidism, even in most early stages of this disease. PATIENT SUMMARY: Kidney stone formation can be linked to calcium metabolism. When high calcium levels are found in urine despite adequate diet changes, a calcium load test may help to understand the underlying mechanisms. Urine and blood levels are explored during a low-calcium diet phase, and after a calcium load phase in the test. The calcium load test is particularly advantageous for revealing abnormally high function of the parathyroid gland, which is called hyperparathyroidism.

SUMMARY INTRODUCTION: Patients with bilateral kidney stones and burdened by large stones are challenging cases for endourologists. Simultaneous bilateral percutaneous nephrolithotomy (sbPCNL) is an option; however, it may be accompanied by important morbidity. An alternative is a staged PCNL, operating one side each time. Herein, we compare the impact of sbPCNL and staged PCNL on complication rates and renal function. METHODS: Patients who underwent sbPCNL or staged bilateral PCNL with a frame time of 6 months were searched in our prospectively collected kidney stone database. Groups were compared for age, gender, body mass index (BMI), comorbidities (classification by the American Society of Anesthesiology - ASA), stone size, Guy's score, stone-free status, renal function, blood loss, blood transfusion rate, complication rate, and length of hospital stay. RESULTS: Twenty-six patients and 52 kidney units were enrolled. The mean operative time was 134.7 min. Only 11.3% of cases had complications, all of them minor (Clavien ≤ 2). Overall, the stone-free rate was 61.50%. Comparing the groups, there was a significantly longer operative time in the sbPCNL group (172.5 vs. 126.3 min; p=0.016), as well as a higher transfusion rate (12.5% vs. 5.6%; p=0.036). There was no statistically significant difference in creatinine levels between the groups. Regarding the stone-free rate, there was a significantly higher proportion of patients in the staged PCNL group (64.9% vs. 43.8%; p=0.012). CONCLUSION: sbPCNL is a safe procedure; however, when compared to staged procedures it has a higher transfusion and lower stone-free rate. RESUMO INTRODUÇÃO: Paciente com cálculos renais bilaterais e de grande volume são casos desafiadores para os endourologistas. A nefrolitotripsia percutânea bilateral simultânea (NLPbs) é um opção, entretanto esse procedimento pode ser acompanhado de morbidade importante. Uma alternativa é a NLP estagiada, operando um lado de cada vez. Aqui, nós comparamos o impacto da NLPbs e da NLP estagiada nas taxas de complicações e função renal. MÉTODOS: Pacientes que foram submetidos a NLPsb ou NLP stagiada com intervalo de até 6 meses foram pesquisados em nossa base de dados de cálculos renais prospectivamente coletada. Os grupos foram comparados em idade, gênero, índice de massa corpórea (IMC), comorbidades (classificação da Sociedade Americana de Anestesiologia – ASA), tamanho do cálculo, Classificação de Guys, taxa de pacientes livres de cálculos, função renal, perda sanguínea, taxa de transfusão, taxa de complicações e tempo de internação hospitalar. RESULTADOS: Vinte e seis paciente e 52 unidades renais foram incluídas. O tempo operatório médio foi de 134,7 min. Apenas 11.3% dos casos tiveram complicações, sendo todas menores (Clavien ≤ 2). No geral, a taxa de pacientes livres de cálculos foi de 61,5%. Comparando os grupos houve um tempo operatório significativamente maior no grupo NLPbs(172,5 vs. 126,3 min; p=0,016), assim como uma maior taxa de transfusão (12,5% vs. 5,6%; p=0.036). Não houve diferença significante nos níveis de creatinina entre os grupos. Em relação a taxa de doentes livre de cálculos houve uma proporção significativamente maior de pacientes livres de cálculos na NLP estagiada (64,9% vs. 43,8%; p=0,012). CONCLUSÃO: A NLPsb é um procedimento seguro, entretando quando comparada ao procedimento estagiado apresenta uma maior taxa de transfusão e uma menor taxa de pacientes livres de cálculos.

To compare noise texture and accuracy to differentiate uric acid from non-uric acid urinary stones among four different single-source and dual-source DECT approaches in an ex vivo phantom study. Thirty-two urinary stones embedded in gelatin were mounted on a Styrofoam disk and placed into a water-filled phantom. The phantom was imaged using four different DECT approaches: (A) dual-source DECT (DS-DE); (B) 1st generation split-filter single-source DECT (SF1-TB); (C) 2nd generation split-filter single-source DECT (SF2-TB) and (D) 2nd generation split-filter single-source DECT using serial acquisitions (SF2-TS). Two different radiation doses (3 mGy and 6 mGy) were used. Noise texture was compared by assessing the average spatial frequency (fav) of the normalized noise power spectrum (nNPS). ROC curves for stone classification were computed and the accuracy for different dual-energy ratio cutoffs was derived. NNPS demonstrated comparable noise texture among A, C, and D (fav-range 0.18–0.19) but finer noise texture for B (fav = 0.27). Stone classification showed an accuracy of 96.9%, 96.9%, 93.8%, 93.8% for A, B, C, D for low-dose, respectively, and 100%, 96.9%, 96.9%, 100% for routine dose. The vendor-specified cutoff for the dual-energy ratio was optimal except for the low-dose scan in D for which the accuracy was improved from 93.8 to 100% using an optimized cutoff. Accuracy to differentiate uric acid from non-uric acid stones was high among four single-source and dual-source DECT approaches for low- and routine dose DECT scans. Noise texture differed only slightly for the first-generation split-filter approach.

Purpose Cystine stones are widely considered hard and difficult to treat. Hounsfield Units (HU) are used in other stone types to estimate ‘hardness’ and treatments based on that finding. Our objective was to report mean HU of cystine stones in vivo in a large case series of cystinuria patients and assess for differences in genotype. Methods A prospective case series of cystinuria patients referred to a specialist centre was analysed. CT imaging was assessed by two independent radiologists to determine in vivo attenuation of cystine calculi. Mean HU was compared for both cystinuria genes (SLC3A1 and SLC7A9) using an independent t-test. Results 164 adult cystinuric patients were identified (55% male), median age 43 years (range 18–80). Median follow up was 31 months (IQR 10–62). Genetic data available for 153/164 (93%) demonstrated 97 SLC3A1 (63%) and 55 (36%) SLC7A9 mutations (39 homozygous, 16 heterozygous) and one heterozygous for both SLC3A1/SLC7A9. 107 patients had CT images available demonstrating calculi. Median HU across the cohort was 633 (5th to 95th centile 328–780). There was no difference in mean HU between SLC3A1 and SLC7A9 genotypes (p = 0.68) or homo and heterozygous SLC7A9 (p = 0.70). Mean HU correlated with stone size (Pearson correlation coefficient = 0.51, p Conclusion In this large single centre cystinuria cohort, mean HU was low for stones that are difficult to treat. Calculi of 1000 are unlikely pure cystine, and in a known cystinuric would suggest conversion to another stone type.

Objectives To evaluate the efficacy and safety of ultraslow full-power shock wave lithotripsy protocol in the management of high attenuation value upper ureteric stones compared with slow-rate, power-ramping shock wave lithotripsy. Methods This was a randomized trial enrolling patients with a single high attenuation value (≥1000 HU) upper ureteric stones between January 2019 and July 2019. Ultraslow full-power shock wave lithotripsy (54 patients) was applied at a rate of 30 shock waves/min with power ramping from 6 to 18 kV for 100 shock waves, then a safety pause for 2 min, followed by ramping 18-22 kV for 100 shock waves, then a safety pause for 2 min. Then, full power (22 kV) was maintained until the end of the session. Slow-rate, power-ramping shock wave lithotripsy (47 patients) was applied at a rate of 60 shock waves/min with power ramping from 6 to 10 kV during the first 500 shock waves, then from 11 to 22 kV during the next 1000 shock waves, then maintained on 22 kV in the last 1500 shock waves. Up to three sessions were carried out with a follow up 3 months after the last session. The primary outcome was the stone-free rate. Perioperative data of the two protocols were compared. Results There was no significant difference in preoperative data. The stone-free rate was significantly higher in ultraslow full-power shock wave lithotripsy after single (92.6% vs 23.4%) and multiple (96.3% vs 63.8%) sessions. Most complications were mild, with no significant difference between both groups (9.3% vs 12.8%; P = 0.573). Logistic regression analysis identified ultraslow full-power shock wave lithotripsy protocol as the only significant independent factor for the stone-free rate (odds ratio 12.589, P = 0.025). Conclusion Ultraslow full-power shock wave lithotripsy for high attenuation value upper ureteric stones is associated with a significantly higher stone-free rate, and with mild complications that are comparable to those of standard shock wave lithotripsy.

Purpose Urinary stones can be successfully treated using a Holmium: Yttrium-Aluminum-Garnet (Ho: YAG) laser. Regarding success rates, laser pulse energy, frequency, and pulse width are well-known contributing factors. Whether the pulse shape might be a further factor influencing the laser efficiency is unclear. This study aimed to evaluate different modes of laser pulse shapes in a real-world setting. Materials and methods The Dornier Medilas® H Solvo (Wesling, Germany) was used in the treatment of ureter and kidney stones. Patients were randomized into standard pulse shape (SPS) and new pulse shape groups (NPS1; ureter) and (NPS2; kidney pelvis), depending on the stone localization. The primary endpoint was laser efficiency defined as mm³ stone destruction per overall operating time. Secondary endpoints encompassed number of stone recoveries and stone-free rate. Results Altogether 145 patients (24 SPS vs. 32 NPS1; 51 SPS vs. 38 NPS2) were included. No differences in sex, age, body mass index, stone localization and stone composition were found, except for preoperative stone size (133±95 [SPS] vs. 197±139 [NPS1] mm³; p=0.023) and (348±298 [SPS] vs. 525±429 [NPS2] mm³; p=0.042). Regarding the primary endpoint, a significant increase in laser efficiency could be detected for the NPS1 and NPS2 groups compared to the SPS groups (39.9±44.9 vs. 28.8±30.2 and 51.7±61.3 vs. 22.4±24.2 mm³/min [mean±standard deviation]). No statistically significant differences were found for secondary endpoints and perioperative complication rates. Conclusions Efficiency of the Ho: YAG laser can be positively influenced by different pulse shapes. This adds the variable of individualized intraoperative decision making.

Patients with staghorn renal stones are challenging cases, requiring careful preoperative evaluation and close follow-up to avoid stone recurrence. In this article we aim to discuss the main topics related to staghorn renal stones with focus on surgical approach. Most of staghorn renal stones are composed of struvite (magnesium ammonium phosphate) and are linked to urinary tract infection by urease-producing pathogens. Preoperative computed tomography scan and careful evaluation of all urine cultures made prior surgery are essential for a well-planning surgical approach and a right antibiotics choice. Gold standard surgical technique is the percutaneous nephrolithotomy (PCNL). In cases of impossible percutaneous renal access, anatrophic nephrolithotomy is an alternative. Shockwave lithotripsy and flexible ureteroscopy are useful tools to treat residual fragments that can be left after treatment of complete staghorn renal stone. PCNL can be performed in supine or prone position according to surgeon’s experience. Tranexamic acid can be used to avoid bleeding. To check postoperative stone-free status, computed tomography is the most accurate imaging exam, but ultrasound combined to KUB is an option. Intra-operative high-resolution fluoroscopy and flexible nephroscopy have been described as an alternative for looking at residual fragments and save radiation exposure. The main goals of treatment are stone-free status, infection eradication, and recurrence prevention. Long-term or short-term antibiotic therapy is recommended and regular control imaging exams and urine culture should be done.

Objective To define current national practice patterns of imaging modalities and urologic procedures in pregnant women with urinary stone disease. Methods Using the IBM MarketScan national insurance claims database, we identified pregnant women with urinary stone disease and their corresponding gestational age between 2011 and 2016 using administrative claims data. We then assessed each encounter for urinary stone disease or stone-related urologic procedure during their pregnancy. We abstracted demographic information as well as codes for stone procedures and imaging. Results We identified 14,298 pregnant women with urinary stone disease during the study period. Of the 12,315 undergoing abdominal imaging (86.1%), magnetic resonance imaging was used in 2.8%, x-ray in 9%, and ultrasound in 74.3%. Computed tomography was not used as a diagnostic modality during pregnancy. Procedural intervention was performed in 749 women (5.2%): 476 (3.3%) ureteral stent placement without definitive stone treatment, 93 (0.6%) percutaneous nephrostomy placement, and 180 (1.3%) ureteroscopy (URS) for definitive stone treatment. URS was most commonly performed before 34 weeks gestation with only 27 cases (15%) performed after. Conclusion This large national cohort reveals the current imaging and procedural practice patterns for urinary stone disease during pregnancy and provides a critical baseline as these practice patterns evolve in the future.

The authors aimed to evaluate the factors affecting clinical outcomes of cystine stone disease in children and to understand the change in disease management over time. Between January 1991 and September 2017, the demographic and clinical data of pediatric patients with documented cystine stone disease were retrospectively analyzed. Patients with at least 12-month follow-up were included. Disease management and clinical outcomes were compared between the first and second 35 patients managed during the study's time frame. A total of 70 patients were included. The female to male ratio was 30/40. The mean age and follow-up period was 29.8 ± 40.1 months and 106.5 ± 56 months, respectively. The mean initial procedure number to treat the first stone episode was 2.4 ± 1.6. Single stone and single affected site were significant predictors for stone clearance. Overall, patients underwent a mean of 5.5 procedure during their follow-up. Recurrence was detected in 71.4% (50/70) of patients. Residual fragments and non-compliance to medical treatment after the initial intervention were significant predictors for recurrence within shorter interval period. 31.4% (22/70) of patients had renal atrophy during follow-up. They were older at the initial diagnosis and had average urine pH lower than 7.5. The first 35 patients had more open procedures. Still, they had more recurrence rate and tend to have more renal atrophy. As a conclusion, cystine stone disease has a recurrent course in children. Stone and fragments entirely removed (SaFER) concept with all minimally invasive methods available and strict follow-up should be the basis for any management plan.

This study aimed to explore the diagnosis of urinary calculi through utilisation of low-dose computed tomography (LDCT) with adaptive statistical iterative reconstruction (ASIR). Data from 140 patients that had undergone pathological or operative diagnosis with urinary calculi were analysed. Patients were divided into two groups based on whether they received conventional-dose computed tomography (CDCT) or LDCT, respectively, followed by filtered back projection or ASIR. Average CDCT radiation doses were roughly 4-fold higher than LDCT doses. Despite this difference, there were no significant differences between groups with respect to stone size or location, image quality (P = 0.261), image noise (P = 0.153) and diagnostic efficacy (P = 0.371). LDCT is an effective approach to urinary calculi diagnosis, performing to ASIR while decreasing the effective radiation dose, improving the safety of this procedure.

Objective To investigate the effects of laser temporal pulse shaping of the super-pulse thulium fibre laser (SPTFL) and to compare these in controlled in vitro conditions with various holmium: yttrium aluminium garnet (Ho:YAG) pulse delivery modes. Materials and methods The SPTFL (Urolase SP, IRE-Polus, Fryazino, Russia), with an emission wavelength of 1.94 μm, and a Ho:YAG laser (P120H; Lumenis, Yokneam, Israel) with Moses technology were compared. Pulse shape, stone retropulsion and ablation efficiency were evaluated using BegoStones and compared for each laser mode: short (SP), long (LP), and Moses pulse (MP) for Ho:YAG, regular pulse (RP) and dual pulse (DP) for SPTFL. Results The Ho:YAG SP mode exhibited an asymmetrical pulse shape, with a steep leading slope and a much more gradual trailing slope, without any flat section. Pulses generated by the SPTFL were significantly longer and therefore had lower peak power than those generated by the Ho:YAG laser at equivalent energy settings. Retropulsion for the holmium:YAG LP and MP modes was similar and lower than that for the SP mode, but higher than for the SPTFL (all P ≤ 0.02), with an average stone displacement approximately four times and two times lower for SPTFL as compared to the Ho:YAG laser. Comparison of ablation volumes indicated that the SPTFL induced significantly higher (twofold) ablation than the Ho:YAG laser. Conclusions The magnitude and initial velocity of stone retropulsion decreased with longer pulse duration and lower pulse peak power, without sacrificing ablation efficiency. These observations are manifest when comparing the Ho:YAG laser with the SPTFL. The novel SPTFL provides greater versatility and control of pulse variables than the Ho:YAG laser. Further clinical investigation of practical benefits achievable with pulse-shaping SPTFL modes is warranted.

Summary Introduction Urolithiasis is a common urological disease whose incidence increases in developed countries. We studied relations between composition of urinary calculi, age and gender. Material An epidemiologic study was conducted in a French population of patients encountered analysis of urinary calculi between 2013 and 2017. This retrospective cohort study was performed from urinary calculi samples analysed in a clinical biochemistry laboratory of University Hospital of Lyon in France. A total of 5782 samples were included. Data, according to stone composition, presence of a papillary umbilication and a Randall's plaque, age and gender, were investigated. Statistical analyses used the Chi2 test (R software). Results The overall male to female sex ratio was equal to 1.76. The average and the median of age were 52.1 and 53.0 years, respectively. Whewellite was the most frequent main component in our population (44.4%). Carbapatite, weddellite and uric acid represented the main component in 14.0%, 13.4% and 13.0% of samples, respectively. Differences between genders were shown. Whewellite and uric acid were more frequent in men (P Conclusions Our study provided recent data on the composition of urinary calculi in a French population and the relations between composition of urinary calculi and age and gender. Level of evidence 3.

Background Renal hypouricemia (RHUC) is a hereditary disorder where mutations in SLC22A12 gene and SLC2A9 gene cause RHUC type 1 (RHUC1) and RHUC type 2 (RHUC2), respectively. These genes regulate renal tubular reabsorption of urates while there exist other genes counterbalancing the net excretion of urates including ABCG2 and SLC17A1. Urate metabolism is tightly interconnected with glucose metabolism, and SLC2A9 gene may be involved in insulin secretion from pancreatic β-cells. On the other hand, a myriad of genes are responsible for the impaired insulin secretion independently of urate metabolism. Case presentation We describe a 67 year-old Japanese man who manifested severe hypouricemia (0.7 mg/dl (3.8–7.0 mg/dl), 41.6 μmol/l (226–416 μmol/l)) and diabetes with impaired insulin secretion. His high urinary fractional excretion of urate (65.5%) and low urinary C-peptide excretion (25.7 μg/day) were compatible with the diagnosis of RHUC and impaired insulin secretion, respectively. Considering the fact that metabolic pathways regulating urates and glucose are closely interconnected, we attempted to delineate the genetic basis of the hypouricemia and the insulin secretion defect observed in this patient using whole exome sequencing. Intriguingly, we found homozygous Trp258* mutations in SLC22A12 gene causing RHUC1 while concurrent mutations reported to be associated with hyperuricemia were also discovered including ABCG2 (Gln141Lys) and SLC17A1 (Thr269Ile). SLC2A9, that also facilitates glucose transport, has been implicated to enhance insulin secretion, however, the non-synonymous mutations found in SLC2A9 gene of this patient were not dysfunctional variants. Therefore, we embarked on a search for causal mutations for his impaired insulin secretion, resulting in identification of multiple mutations in HNF1A gene (MODY3) as well as other genes that play roles in pancreatic β-cells. Among them, the Leu80fs in the homeobox gene NKX6.1 was an unreported mutation. Conclusion We found a case of RHUC1 carrying mutations in SLC22A12 gene accompanied with compensatory mutations associated with hyperuricemia, representing the first report showing coexistence of the mutations with opposed potential to regulate urate concentrations. On the other hand, independent gene mutations may be responsible for his impaired insulin secretion, which contains novel mutations in key genes in the pancreatic β-cell functions that deserve further scrutiny.

Urinary stone disease during pregnancy is poorly understood but is thought to be associated with increased maternal and fetal morbidity. We determined the prevalence of urinary stone disease in pregnancy and whether it is associated with adverse pregnancy outcomes.We identified all pregnant women from 2003 through 2017 in the Optum® national insurance claims database. We used diagnosis claims to identify urinary stone disease and assess medical comorbidity. We established the prevalence of urinary stone disease during pregnancy stratified by week of pregnancy. We further evaluated associations among urinary stone disease, maternal complications and pregnancy outcomes in univariable and multivariable analyses.Urinary stone disease affects 8 per 1,000 pregnancies and is more common in white women and women with more comorbid conditions. In fully adjusted models pregnancies complicated by urinary stone disease had higher rates of adverse fetal outcomes including prematurity and spontaneous abortions. This analysis is limited by its retrospective, administrative claims design.The rate of urinary stone disease during pregnancy is higher than previously reported. Urinary stone disease is associated with adverse pregnancy outcomes.

Renal hypouricemia sometimes leads to exercise-induced acute kidney injury (EIAKI) of unknown pathogenesis. In order to elucidate the various pathological conditions associated with hypouricemia, we analyzed the effects of low uric acid level on energy metabolism. We have modified semi-ischemic forearm exercise test and performed this test in one Japanese healthy volunteer, three patients with hereditary renal hypouricemia and one patient with hereditary xanthinuria of Czech origin. Forearm exercise was performed by squeezing a hand dynamometer with the sphygmomanometer cuff pressure kept at the mean arterial pressure. Venous blood was drawn five times (before exercise, 3, 10, 30, 45 minutes after the start of exercise) in each tests. The mean plasma lactate concentration increased from a baseline of 1.3 (range 0.7-1.8 mmol/L) to 4.0 (range 2.0-5.5 mmol/L) at 3 minutes after the start of exercise. The plasma hypoxanthine concentrations were quite low before exercise (0-2.9 μmol/L), but increased markedly to a range of 13.6-28.8 μmol/L after 10 minute forearm ischemia. Our protocol allowed us to conclude that the load was sufficient for observing metabolic changes in temporally hypoxia and in following recovery phase. The test was well tolerated and safe, we did not observe any adverse reactions including EIAKI.

Urolithiasis has become more prevalent throughout China.Knowing stone composition helps identify their possible underlying etiology of urolithiasis, provide appropriate individualized treatment and prevent stone recurrence.To explore characteristics of urinary stone composition in China, and determine the effects of gender, age, body mass index (BMI), stone localization and geographical region on stone composition.We used Fourier transform infrared spectroscopy to analyse urinary stones from consecutive patients at 46 hospitals in seven geographic areas of China between June 1, 2010 and May 31, 2015.Chi-squared tests and logistic regression analyses were performed to determine associations between stone composition and sex, age, body mass index (BMI), stone location, and geographic region.The most common stone components were calcium oxalate (CaOx; 65.9%), carbapatite (15.6%), urate (12.4%), struvite (2.7%), brushite (1.7%), and cystine (0.9%). CaOx and urate occurred more frequently in males, whereas carbapatite and struvite were more common in females (p

Purpose of review Urinary stone disease (USD) is increasing in prevalence and recurrence is common. In pediatrics, most stones are composed primarily of calcium with the highest incidence observed in adolescents. Given the morbidity associated with USD, an in depth review of current management strategies is of paramount importance to highlight the data supporting the recommended treatments and the knowledge gaps which still exist. Recent findings Several interventions for the management of recurrent calcium USD in children have been recommended based on primarily adult studies. These interventions include modification of diet and fluid intake in addition to the utilization of medications such as thiazide diuretics and citrates when supportive care is inadequate. Overall there is conflicting data in the adult literature which is further complicated by our attempts to extrapolate these data to children. Summary Based on the currently available literature the management of USD in pediatrics should be individualized to each patient and focused on the particular metabolic risk factors that are identified during the course of their evaluation. Several interventions may be required or trialed in a particular patient to show an effect. Well designed trials to assess the efficacy of each intervention in the pediatric population are needed.