Diagnosis and Management of Urinary Stone Disease in Pregnancy: Integrating Current Guidelines with Emerging Evidence.

The incidence of stone disease has been increasing and the risk of recurrent stone formation is high in a pediatric population. It is crucial to use the most effective method with the primary goal of complete stone removal to prevent recurrence from residual fragments. While extracorporeal shock wave lithotripsy (ESWL) is still considered first line therapy in many clinics for urinary tract stones in children, endoscopic techniques are widely preferred due to miniaturization of instruments and evolution of surgical techniques. The standard procedures to treat urinary stone disease in children are the same as those used in an adult population. These include ESWL, ureterorenoscopy, percutaneous nephrolithotomy (standard PCNL or mini-perc), laparoscopic and open surgery. ESWL is currently the procedure of choice for treating most upper urinary tract calculi in a pediatric population. In recent years, endourological management of pediatric urinary stone disease is preferred in many centers with increasing experience in endourological techniques and decreasing sizes of surgical equipment. The management of pediatric stone disease has evolved with improvements in the technique and a decrease in the size of surgical instruments. Recently, endoscopic methods have been safely and effectively used in children with minor complications. In this review, we aim to summarize the recent management of urolithiasis in children.

Transforming urinary stone disease management by artificial intelligence-based methods: A comprehensive review

Urinary tract stone disease is one of the most common cases in urology. These cases are increasing nearly 12% every year. Most cases occur in age group 40 to 60 years, and more common in male about three to four times than female. Patient with urinary tract stone at Tabanan General Hospital, always increase and recurrence rate still high. This is a descriptive-retrospective study. Samples are taken from all urology patients diagnosed with urinary stone disease at operating room of Tabanan Hospital between July 2014 to June 2016. We collected data from medical record regarding sex, age, living area, comorbidities, stone location, and management of urinary stone disease. Total 226 cases with urinary stone disease were managed at operating room of Tabanan General Hospital. Half of these patients aged between 46 to 60 years old, with sex ratio male two times higher than female. Hypertension is one of comorbidities for patient with urinary tract stone. Most of Kidney stone were treated by PCNL, ureter stone by URS and bladder stone by lithotripsy. In conclusion, urinary tract stone disease in Tabanan General Hospital commonly occurs in male, age more than 45 years old and mostly comes from urban area. The management of the patient tends to move from invasive approach to less invasive approach.

Changes in Urinary Stone Risk Factors in Hypocitraturic Calcium Oxalate Stone Formers Treated With Dietary Sodium Supplementation

Urinary Stone Disease in Pregnancy: A Claims Based Analysis of 1.4 Million Patients.

We aimed to review the trends and incidence of surgical intervention for adults with upper urinary tract stones in Ontario, Canada, and to hypothesize potential causes for the observed changes. We carried out a retrospective, population-based cohort study using administrative databases held at the Institute of Clinical Evaluative Sciences (ICES) to identify all adults (≥18 years) who underwent surgical treatment for urolithiasis, defined by records using a combination of both hospital and physician billing from 2002-2019. Descriptive statistics were used to summarize baseline patient demographics, and surgical trends were analyzed using the Cochrane-Armitage test for trend. From 2002-2019, 140 263 patients were treated surgically for urolithiasis. During this time period, the total number of surgically treated stone disease increased by 80.5%. By type of procedure, percutaneous nephrolithotomy (PCNL) increased by 187% and ureteroscopy (URS) increased by 158%, while the number of shockwave lithotripsy (SWL) declined by 31.4%. The adult population in Ontario in the years evaluated grew by 24.4%. The number of surgical procedures per 100 000 people over this time grew by 45.3%. For every 1% increase in the population, there was a 2.6% rise in stone-related surgical procedures. The number of stone-related surgical procedures performed rose significantly and cannot be accounted for by population growth alone. This rise was proportionally larger in the female population, further supporting a narrowing of the gender gap in urinary stone disease. The reasons for the increase are likely multifactorial and may imply an increasing incidence of surgically treated stone disease. The change in the proportion of URS and SWL performed may demonstrate a continued shift in surgical preference or may be reflective of resource limitations and availability. The increase in PCNL volumes may also suggest a greater complexity of cases. These findings should be considered for future resource planning and require further study.

The diverse manifestations of urolithiasis provide a very interesting epidemiological study from the standpoints of geography, socioeconomic status, nutrition and culture. Stone disease not only affects the patient, but also the national economy, as the disease is prevalent in the productive age group. There has been a continuous search for the cost-effectiveness of different treatment modalities not only to treat the patient but also to prevent its recurrence. The various socioeconomic and dietary factors playing roles in the etiology of urinary calculi in the stone-prevalent areas of the world were analyzed. The impact of urinary tract stone disease on the socioeconomic infrastructure of the patient and national economy was studied. A cost-effectiveness analysis vis-à-vis the safety and efficacy of various treatment modalities in both developed and developing countries was done. The standard of living and level of nutrition have directly influenced the process of urolithiasis amongst the communities of the world. A low socioeconomic status has been linked to endemic bladder calculi seen in many poor countries with people subsisting on a deficient diet. The incidence of upper urinary tract calculi increases with prosperity and more nutritious diets. Replacement of open surgery with minimally invasive techniques (ESWL, PCNL, URS) for treating stones in the urinary tract has greatly reduced the patients' morbidity and mortality and the period of hospitalization and convalescence. This change in treatment has also led to less days of absence from work and could minimize the loss to national economy. Minimally invasive surgery is more cost effective in developed countries because of the short hospital stay. However, in developing countries open surgery still appears to be cost-effective in certain subset of the patients. There is a need for proper health care and a medical insurance system to take care of the financial burden, especially in developing countries, of a disease with a high magnitude of recurrence and morbidity. The need and type of medical treatment should be appraised continually to accommodate advances in techniques of stone removal. Lastly, the quest for etiology, cost-effective treatment and prevention still continues and even today we cannot stay better than Frère Jacques, 'I have removed the stone, it is up to God to cure the patient'.

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 integrated on guidewires, scopes, access sheath and use of innovative platforms regulating irrigation/suction systems. Direct In-Scope Suction (DISS) system was developed to control intrarenal pressure and facilitate the removal of residual fragments. Flexible and Navigable Suction Ureteral Access Sheath (FANS-UAS) is a flexi-bendable UAS equipped with suction capabilities combining mechanical flexibility with continuous irrigation management and stone clearance mechanisms. Ultra-thin scopes (7.5 F) make it easy to perform RIRS without the need for pre-placed double-J stents or with a 9 F sheath achieving more space for stone fragments expulsion or infusion. All these technological advancements have enhanced the efficacy of fURS or RIRS which can be an alternative treatment (salvage fURS) when standard stone management techniques, such as percutaneous nephrolithotomy (PCNL), are contraindicated or fail. Salvage fURS has shown favorable outcomes in complex or high-risk cases, including patients with coagulopathies, morbid obesity, renal anatomical abnormalities (e.g., horseshoe or pelvic kidneys), urinary diversion, calyceal diverticula, and altered urinary tracts. In such scenarios it demonstrated favorable outcomes with stone-free rates ranging from 55.6% to 64% for stones > 2 cm. Although non-invasive, extracorporeal and endoscopic treatments for renal and ureteral stones carry a risk of complications that can be classified according to the Clavien-Dindo system. The complication rate after SWL was estimated at 18.43% for Clavien grade I-II complications (pain, hematuria) and 2.48% for Clavien III-IV complications (hematoma, sepsis). The most frequent complication after RIRS is fever or urinary tract infection observed in 0.2-15% (with 0.1-4.3% of cases of urinary sepsis). Complications after PCNL are more frequent and may include moderate events (hemorrhage requiring transfusion 2-7%, urosepsis 1-2%, bowel injury < 1%) as well as severe events (arteriovenous fistula 0.5-1%, thoracic complications < 1% , loss of access tract 1-3%, death < 0.5%). The risk of bleeding complications is significantly increased in patients on antithrombotic therapy. A personalized, interdisciplinary approach enables optimal decision-making in balancing antithrombotic therapy with surgical safety during urological stone interventions Finally, it must be considered that endourological procedures can be harmful to the surgeons themselves and their team due to exposure to ionizing radiation. For this reason, procedures must be carried out in strict accordance with safety guidelines and regulations to minimize radiation exposure. Safety is vital in any surgical intervention, with efficacy being the next most critical consideration. However, cost-effectiveness should be also considered. Endourology involves high costs largely due to the use of sophisticated equipment that requires frequent renewal due to the continuous rapid technological evolution. Using disposable devices brings numerous benefits but also leads to a further increase in costs. Finally, in the cost-benefit assessment, the rate of reintervention associated with some types of procedures must be considered.

ObjectiveThe American Urological Association guidelines recommend 24-hour urine testing in patients with urinary stone disease to decrease the risk of stone recurrence; however, national practice patterns for 24-hour urine testing are not well characterized. Our objective is to determine the prevalence of 24-hour urine testing in patients with urinary stone disease in the Veterans Health Administration and examine patient-specific and facility-level factors associated with 24-hour urine testing. Identifying variations in clinical practice can inform future quality improvement efforts in the management of urinary stone disease in integrated healthcare systems.Materials and methodsWe accessed national Veterans Health Administration data through the Corporate Data Warehouse (CDW), hosted by the Veterans Affairs Informatics and Computing Infrastructure (VINCI), to identify patients with urinary stone disease. We defined stone formers as Veterans with one inpatient ICD-9 code for kidney or ureteral stones, two or more outpatient ICD-9 codes for kidney or ureteral stones, or one or more CPT codes for kidney or ureteral stone procedures from 2007 through 2013. We defined a 24-hour urine test as a 24-hour collection for calcium, oxalate, citrate or sulfate. We used multivariable regression to assess demographic, geographic, and selected clinical factors associated with 24-hour urine testing.ResultsWe identified 130,489 Veterans with urinary stone disease; 19,288 (14.8%) underwent 24-hour urine testing. Patients who completed 24-hour urine testing were younger, had fewer comorbidities, and were more likely to be White. Utilization of 24-hour urine testing varied widely by geography and facility, the latter ranging from 1 to 40%.ConclusionsFewer than one in six patients with urinary stone disease complete 24-hour urine testing in the Veterans Health Administration. In addition, utilization of 24-hour urine testing varies widely by facility identifying a target area for improvement in the care of patients with urinary stone disease. Future efforts to increase utilization of 24-hour urine testing and improve clinician awareness of targeted approaches to stone prevention may be warranted to reduce the morbidity and cost of urinary stone disease.

Acute flank pain, with or without hematuria, is a common complaint and urolithiasis is the primary consideration in many of these patients. Clinical findings are often nonspecific and may overlap other conditions. Imaging plays an important role in both diagnosis and subsequent management of urinary stone disease. Radiological imaging of urinary stones dates back to 1897, the year after Roentgen’ s discovery of X-rays. Early attempts at opacification of the urinary tract included retrograde placement of ureteral intraluminal wires and opaque catheters, air, colloidal silver, and sodium iodide (1). Iodinated contrast agents that were excreted by the kidneys and could be administered intravenously were developed in the 1920s. For the next 70 yr, intravenous pyelography or excretory urography, including a preliminary noncontrast scout view, was the primary modality for imaging urinary stones. Computed tomography (CT) was introduced in the mid-1970s. Early CT scanners could sometimes visualize urinary calculi, but CT was not a reliable method to confidently exclude stones because these slower nonhelical scanners were plagued by misregistration between sequential images. Stones present in these nonvisualized gaps could escape detection. If seen, stone size was frequently underestimated if only the top or bottom edge of the stone was included in the slice. For these reasons, nonhelical CT was unsuitable for the primary work-up of suspected urolithiasis. The introduction of helical CT scanners in the early 1990s revolutionized the imaging of urinary stone disease. With these more rapid helical CT scanners, large anatomic regions could be scanned during a single breath hold with thin slices and no misregistration. Multislice helical scanners, introduced in the late 1990s, led to the ability to obtain even thinner slices in less time, allowing the detection of smaller, less dense calculi and reducing the likelihood of false-negative scans. In most centers, nonenhanced CT has replaced the intravenous urography (IVU) as the modality of choice for the imaging of urinary stones.Key WordsComputed tomographyurogramradiographobstruction

Care Navigation in the Management of Urinary Stone Disease: An Opportunity to Improve Care Access While Reducing Treatment Costs.

Surgery for upper tract urinary stone disease is often reserved for symptomatic patients and those whose stone does not spontaneously pass after a trial of passage. Our objective was to determine whether payer type or race/ethnicity is associated with the timeliness of kidney stone surgery. A population-based cohort study was conducted using the California Office of Statewide Health Planning and Development dataset from 2010 to 2012. We identified patients who were discharged from an emergency department (ED) with a stone diagnosis and who subsequently underwent a stone surgery. Primary outcome was time from ED discharge to urinary stone surgery in days. Secondary outcomes included potential harms resulting from delayed stone surgery. Over the study period, 15,193 patients met the inclusion criteria. Median time from ED discharge to stone surgery was 28 days. On multivariable analysis patients with Medicaid, Medicare, and self-pay coverage experienced adjusted mean increases of 46%, 42%, and 60% in time to surgery, respectively, when compared with those with private insurance. In addition, patients of Black and Hispanic race/ethnicity, respectively, experienced adjusted mean increases of 36% and 20% in time to surgery relative to their White counterparts. Before a stone surgery, underinsured patients were more likely to revisit an ED three or more times, undergo two or more CT imaging studies, and receive upper urinary tract decompression. Underinsured and minority patients are more likely to experience a longer time to stone surgery after presenting to an ED and experience potential harm from this delay.

Urinary stone disease in pregnancy is an important clinical scenario which presents unique challenges to the urologist. In order to ensure safe and comprehensive care of both the mother and the fetus, a multidisciplinary approach is highly recommended. A high degree of suspicion is required for the prompt and accurate diagnosis of renal colic during pregnancy. Given the potential serious risks of radiation exposure during pregnancy, careful consideration must be given to the use of diagnostic imaging in this context. Management must be individualized to the patient and clinical situation but generally proceeds from conservative to more invasive approaches. Expectant management is recommended as first-line treatment when there are no contraindications. However, recent advances in endourological equipment and techniques and obstetrical care have allowed for an increased role of primary surgical management with ureteroscopy. It is essential for the practicing urologist to understand the intricacies of diagnosing and managing stone disease in pregnancy in order to reduce the potential for patient morbidity and complications.

Urinary stone disease in pregnancy is an important clinical scenario which presents unique challenges to the urologist. In order to ensure safe and comprehensive care of both the mother and the fetus, a multidisciplinary approach is highly recommended. A high degree of suspicion is required for the prompt and accurate diagnosis of renal colic during pregnancy. Given the potential serious risks of radiation exposure during pregnancy, careful consideration must be given to the use of diagnostic imaging in this context. Management must be individualized to the patient and clinical situation but generally proceeds from conservative to more invasive approaches. Expectant management is recommended as first-line treatment when there are no contraindications. However, recent advances in endourological equipment and techniques and obstetrical care have allowed for an increased role of primary surgical management with ureteroscopy. It is essential for the practicing urologist to understand the intricacies of diagnosing and managing stone disease in pregnancy in order to reduce the potential for patient morbidity and complications.

Clinical Trials of the Surgical Management of Urolithiasis: Current Status and Future Needs