Natural History of Conservatively Managed Ureteral Stones: Analysis of 6600 Patients

Prediction of spontaneous distal ureteral stone passage using artificial intelligence

PURPOSE

Identifying factors predicting the spontaneous passage of distal ureteral stones and evaluating the effectiveness of artificial intelligence in prediction.

MATERIALS AND METHODS

The files of patients presenting with distal ureteral stones were retrospectively evaluated. Those who experienced spontaneous passage were assigned to Group P, while those who did not were assigned to Group N. Demographic and clinical data of both groups were compared. Then, logistic regression analysis was performed to determine the factors predicting spontaneous stone passage. Based on these factors, a logistic regression model was prepared, and artificial intelligence algorithms trained on the dataset were compared with this model to evaluate the effectiveness of artificial intelligence in predicting spontaneous stone passage.

RESULTS

When comparing stone characteristics and NCCT findings, it was found that the stone size was significantly smaller in Group P (4.9 ± 1.7 mm vs. 6.8 ± 1.4 mm), while the ureteral diameter was significantly higher in Group P (3.3 ± 0.9 mm vs. 3.1 ± 1.1 mm) (p < 0.05). Parameters such as stone HU, stone radiopacity, renal pelvis AP diameter, and perirenal stranding were similar between the groups. In multivariate analysis, stone size and alpha-blocker usage were significant factors in predicting spontaneous stone passage. The ROC analysis for the logistic regression model constructed from the significant variables revealed an area under the curve (AUC) of 0.835, with sensitivity of 80.1% and specificity of 68.4%. AI algorithms predicted the spontaneous stone passage up to 92% sensitivity and up to 86% specifity.

CONCLUSIONS

AI algorithms are high-powered alternatives that can be used in the prediction of spontaneous distal ureteral stone passage.

Obstructive uropathy: Overview of the pathogenesis, etiology and management of a prevalent cause of acute kidney injury

Obstructive uropathy is defined as the structural or functional interruption of urinary outflow at any level in the urinary tract. It is regarded as one of the most prevalent causes of acute kidney injury (AKI), accounting for 5%–10% of cases. Acute severe obstruction of the urinary tract is a potentially threatening situation for the kidneys and therefore requires prompt identification and management to relieve obstruction. The aim of the present article is to review and synthesize available evidence on obstructive uropathy, providing a clinical guideline for clinicians. A literature review on obstructive uropathy in the context of AKI was performed, focusing on the least clarified aspects regarding diagnosis and management. Recent literature searching was conducted in English and top-level evidence articles including systematic reviews, metanalyses and large series were prioritized. Acute obstruction of the urinary tract is a diagnostic and therapeutical challenge that may lead to important clinical complications together with direct structural and hemodynamic damage to the kidney. Early recognition of the leading cause and its exact location is essential to ensure prompt urinary drainage together with the most suitable drainage technique selection. A multidisciplinary approach, including urologists, nephrologists, and other medical specialties, is best suited to correctly manage concomitant hemodynamic changes, fluid and electrolyte imbalances, and other related issues. Obstructive uropathy is one of the leading causes of AKI. Recognition of patients suitable for early diversion and feasibility or adequate selection of the indicated technique is sometimes challenging. A thorough understanding of the physiopathology behind the development of urinary obstruction is vital for correct diagnosis and management.

Deciding on a novel predictive value to gauge how well patients with lower ureteric stones respond to medical expulsive therapy

This study, conducted over 4 years in Baghdad, Iraq, aimed to determine the importance of ureteric jet assessment in medical expulsive therapy (MET) for distal ureteral stones. A total of 156 patients with distal ureteral stones (≤ 10 mm) participated, and their ureteric jets were observed using a color Doppler scanner before and after 2 weeks of MET. The main focus was the success rate of stone expulsion. Our results showed that 50% of patients had detectable ureteric jets after 2 weeks of MET, and 21.8% experienced successful stone expulsion. After 4 weeks, 23.7% achieved stone expulsion, while 54.5% still had remaining stones. Patients who had a positive baseline ureteric jet were significantly more likely to successfully expel their stones. This study highlights the importance of monitoring ureteric jet movement in MET for distal ureteral stones.

Acupuncture for response and complete pain relief time of acute renal colic: Secondary analysis of a randomized controlled trial

Background

The integration of acupuncture with intramuscular injection of diclofenac sodium can expedite the onset of analgesia in treating acute renal colic caused by urolithiasis. However, it remains unclear whether acupuncture can accelerate pain relief constantly until complete remission. This study aimed to explore the extent to which acupuncture can expedite the onset time of response or complete pain relief in treating acute renal colic, and the predictive value of patient characteristics for treatment efficacy.

Methods

This secondary analysis utilized data from a prior randomized controlled trial. Eighty patients with acute renal colic were randomly assigned 1:1 to the acupuncture group or the sham acupuncture group. After intramuscular injection of diclofenac sodium, acupuncture or sham acupuncture was delivered to patients. The outcomes included time to response (at least a 50 % reduction in pain) and complete pain relief. Between-group comparison under the 2 events was estimated by Kaplan-Meier methodology. Subgroup analysis was performed utilizing the Cox proportional hazards model.

Results

The median response time and complete pain relief time in the acupuncture group were lower than those in the sham acupuncture group (5 vs 30 min, Log Rank P < 0.001; 20 min vs not observed, Log Rank P < 0.001, respectively). Hazard Ratios (HRs) for response across all subgroups favored the acupuncture group. All HRs for complete pain relief favored acupuncture, expect large stone and moderate pain at baseline. No interaction was found in either event.

Conclusion

Acupuncture can accelerate the response time and complete pain relief time for patients with acute renal colic, with the efficacy universally.

Trial registration

This study has been registered at Chinese Clinical Trial Registry: ChiCTR1900025202.

Urological Guidelines for Kidney Stones: Overview and Comprehensive Update

BACKGROUND

Evidence-based guidelines are published by urological organisations for various conditions, including urolithiasis. In this paper, we provide guidance on the management of kidney stone disease (KSD) and compare the American Urological Association (AUA) and European Association of Urologists (EAU) guidelines.

METHODS

We evaluate and appraise the evidence and grade of recommendation provided by the AUA and EAU guidelines on urolithiasis (both surgical and medical management).

RESULTS

Both the AUA and EAU guidelines provide guidance on the type of imaging, treatment options, and medical therapies and advice on specific patient groups, such as in paediatrics and pregnancy. While the guidelines are generally aligned and based on evidence, some subtle differences exist in the recommendations, but both are generally unanimous for the majority of the principles of management.

CONCLUSIONS

We recommend that the guidelines should undergo regular updates based on recently published material, and while these guidelines provide a framework, treatment plans should still be personalised, respecting patient preferences, surgical expertise, and various other individual factors, to offer the best outcome for kidney stone patients.

The role of the general practictioner in the management of urinary calculi

BACKGROUND

The prevalence of kidney stones tends to increase worldwide due to dietary and climate changes. Disease management involves a high consumption of healthcare system resources which can be reduced with primary prevention measures and prophylaxis of recurrences. In this field, collaboration between general practitioners (GPs) and hospitals is crucial.

METHODS

a panel composed of general practitioners and academic and hospital clinicians expert in the treatment of urinary stones met with the aim of identifying the activities that require the participation of the GP in the management process of the kidney stone patient.

RESULTS

Collaboration between GP and hospital was found crucial in the treatment of renal colic and its infectious complications, expulsive treatment of ureteral stones, chemolysis of uric acid stones, long-term follow-up after active treatment of urinary stones, prevention of recurrence and primary prevention in the general population.

CONCLUSIONS

The role of the GP is crucial in the management and prevention of urinary stones. Community hospitals which are normally led by GPs in liaison with consultants and other health professional can have a role in assisting multidisciplinary working as extended primary care.

Efficacy of mirabegron for ureteral stones: a systematic review with meta-analysis of randomized controlled trials

Background: Medical expulsive therapy demonstrates efficacy in managing ureteral stones in patients amenable to conservative interventions. This meta-analysis aims to evaluate the effectiveness of mirabegron in the treatment of ureteral stones. Methods: From conception to November 2023, we examined PubMed databases, the Cochrane Library, Embase, Ovid, Scopus, and trial registries for this systematic review and meta-analysis. We chose relevant randomized controlled trials (RCTs) evaluating the efficacy of mirabegron as an expulsive treatment for ureteral stones. The Cochrane risk of bias method was used to assess the quality of the evidence. Outcome measures, which included the stone expulsion rate (SER), expulsion time, and pain episodes, were analyzed using RevMan 5.4 and Stata 17. Results: Seven RCTs (N = 701) had enough information and were ultimately included. In patients with ureteral stones, mirabegron-treated patients had a substantially higher SER [odds ratio (OR) = 2.57, 95% confidence interval (CI) = 1.41-4.68, p = 0.002] than placebo-treated patients. Subgroup analysis revealed that mirabegron was superior to placebo in patients with small ureteral stones (OR = 2.26, 95% CI = 1.05-4.87, p = 0.04), with no heterogeneity between studies (p = 0.54; I2 = 0%). Mirabegron patients had a higher SER than the control group for distal ureteral stones (DUSs) (OR = 2.48, 95% CI = 1.31-4.68, p = 0.005). However, there was no difference in stone ejection time or pain episodes between groups. Conclusion: Mirabegron considerably improves SER in patients with ureteral stones, and the effect appears to be more pronounced for small and DUSs. Nevertheless, mirabegron treatment was not associated with improved stone expulsion time or pain management.

2022 Recommendations of the AFU Lithiasis Committee: Summary of indications

The spontaneous elimination rate of ureteral stones decreases with their size, but also in function of their location. The objectives of stone surveillance are to detect the occurrence of a complication (e.g., fever, clinical tolerance) and to verify the potential stone migration/elimination. The use of urological procedures and the choice of technique are based on many different factors. Kidney stone surveillance is proposed mainly to people with low risk of progression or complications (size<4mm and/or lower calyx location and non-infection stone). Surveillance may be extended to patients with larger stones, in function of the clinical context and comorbidities. Conversely, a urological procedure may also be proposed to patients with stones<4mm for professional (e.g., soldier, pilot, expatriate) or social reasons or if travelling is planned. The choice of technique is based on the stone composition (if already known) and density, the advantages and limitations of each technique, and also the clinical context, while trying to choose the least invasive procedure for a stone-free objective. METHODOLOGY: These recommendations were developed using two methods: the Clinical Practice Recommendations method (CPR) and the ADAPTE method, depending on whether the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis) [EAU 2022] and their adaptability to the French context. This chapter is based on the references used in the chapters on the different techniques (extracorporeal shock wave therapy, ureteroscopy, percutaneous nephrolithotomy, medical expulsive therapy, postural therapy, chemolysis by alkalinization) as well as the American Urological Association (AUA) and EAU recommendations.

Comparison of endoscopic versus CT assessment of stone-free status after percutaneous nephrolithotomy (PCNL)

This study is aimed to determine whether postoperative low dose computed tomography (LDCT) imaging is necessary after percutaneous nephrolithotomy (PCNL), or the surgeon's intraoperative assessment of residual fragments (RF) is sufficient and avoidance of postoperative imaging with reduction of radiation exposure can be achieved. Data of all 610 patients who underwent PCNL in prone position in our institution from February 2009 to September 2020 was collected. Parameters such as age, gender, BMI, ASA-Classification, stone related parameters and the surgeon's assessment of stone-free status were analyzed. The LDCT performed postoperatively was compared to the intraoperative assessment of the surgeon regarding RF. The mean age of patients was 52.82 years; the mean BMI was 28.18 kg/m2. In 418 cases, the surgeon made a clear statement about the presence of RF and postoperative LDCT was carried out. The discrepancy between the two methods (surgeon´s assessment vs. LDCT) was significant at p < 0.0001. The sensitivity, specificity, positive and negative predictive value of the surgeon when assessing RF were 24.05%, 99.45%, 98.28% and 50%. Stone free rate (SFR) after primary PCNL was 45.57%. The overall SFR at discharge was 96.23%. Although the surgeon´s assessment of RF was reliable, postoperative LDCT imaging should still be performed if endoscopic stone clearance is suspected due to the high false negative rate and the low negative predictive value. The optimal timing of postoperative imaging following PCNL remains unclear.

A prospective evaluation of patient-reported outcomes during follow-up of ureteral stones managed with medical expulsive treatment (MET)

Patient-reported outcomes (PROs) for ureteral stones predominantly assess the pain. Despite the lack of evidence, multiple trials studying the efficacy of medical expulsive therapy (MET) have used PROs to define spontaneous stone passage (SSP). We aim to objectively evaluate the accuracy of PROs to predict successful SSP and the probability of patient's symptom resolution after stone passage. A single-center, prospective observational study recruiting adults with isolated, uncomplicated, ≤ 10 mm ureteral calculus was conducted. All patients received 4 weeks of MET, and SSP was confirmed by low-dose non-contrast-enhanced computed tomography (NCCT). The accuracy of PROs: "pain cessation," "decreased pain," "stone seen," and "stone capture" to predict successful SSP were evaluated in 1 month. The patient's symptom resolution rate was assessed at 1 and 4-month follow-ups. A total of 171 patients were included, and the overall SSP rate was 66.4% (n = 99). Patient-reported pain cessation, stone visualization, and stone capture were associated with successful SSP, but their accuracy was 59, 53, and 43%, respectively. Moreover, 25% of patients reporting complete pain cessation still harbored ureteral calculus. Pain resolved in 91% of patients after SSP at a 4-month follow-up. While hematuria and nausea resolved in all patients, lower urinary tract symptoms (LUTS) were not resolved in 17% of patients. We concluded that patient-reported pain cessation, stone visualization, and stone capture predict successful SSP, but confirmatory imaging is required due to the poor accuracy of these measures. The significant rates of non-pain-related symptoms indicate their significant contribution to patient morbidity. Clinical Trial Registration: Registered in Clinical Trial Registry of India (CTRI), Registration number: CTRI/2020/10/028777 (29th October 2020).

Opioid Analgesic Use After an Acute Pain Visit: Evidence from a Urolithiasis Patient Cohort

Introduction: Urolithiasis causes severe acute pain and is commonly treated with opioid analgesics in the emergency department (ED). We examined opioid analgesic use after episodes of acute pain. Methods: Using data from a longitudinal trial of ED patients with urolithiasis, we constructed multivariable models to estimate the adjusted probability of opioid analgesic use 3, 7, 30, and 90 days after ED discharge. We used multiple imputation to account for missing data and weighting to account for the propensity to be prescribed an opioid analgesic at ED discharge. We used weighted multivariable regression to compare longitudinal opioid analgesic use for those prescribed vs not prescribed an opioid analgesic at discharge, stratified by reported pain at ED discharge. Results: Among 892 adult ED patients with urolithiasis, 79% were prescribed an opioid analgesic at ED discharge. Regardless of reporting pain at ED discharge, those who were prescribed an opioid analgesic were significantly more likely to report using it one, three, and seven days after the visit in weighted multivariable analysis. Among those who were not prescribed an opioid analgesic, an estimated 21% (not reporting pain at ED discharge) and 30% (reporting pain at discharge) reported opioid analgesic use at day three. Among those prescribed an opioid analgesic, 49% (no pain at discharge) and 52% (with pain at discharge) reported using an opioid analgesic at day three. Conclusion: Urolithiasis patients who received an opioid analgesic at ED discharge were more likely to continue using an opioid analgesic than those who did not receive a prescription at the initial visit, despite the time-limited nature of urolithiasis.

A machine learning model for predicting surgical intervention in renal colic due to ureteral stone(s) < 5 mm

A 75-89% expulsion rate is reported for ureteric stones ≤ 5 mm. We explored which parameters predict justified surgical intervention in cases of pain caused by < 5 mm ureteral stones. We retrospectively reviewed all patients with renal colic caused by ureteral stone < 5 mm admitted to our urology department between 2016 and 2021. Data on age, sex, body mass index, the presence of associated hydronephrosis/stranding on images, ureteral side, stone location, medical history, serum blood count, creatinine, C-reactive protein, and vital signs were obtained upon admission. XGboost (XG), a machine learning model has been implemented to predict the need for intervention. A total of 471 patients (median age 49, 83% males) were reviewed. 74% of the stones were located in the distal ureter. 160 (34%) patients who sustained persistent pain underwent surgical intervention. The operated patients had proximal stone location (56% vs. 10%, p < 0.001) larger stones (4 mm vs. 3 mm, p < 0.001), longer length of stay (3.5 vs. 3 days, p < 0.001) and more emergency-room (ER) visits prior to index admission (2 vs. 1, p = 0.007) compared to those who had no surgical intervention. The model accuracy was 0.8. Larger stone size and proximal location were the most important features in predicting the need for intervention. Altogether with pulse and ER visits, they contributed 73% of the final prediction for each patient. Although a high expulsion rate is expected for ureteral stones < 5 mm, some may be painful and drawn out in spontaneous passage. Decision-making for surgical intervention can be facilitated by the use of the present prediction model.

[Follow-up after urolithiasis management]

BACKGROUND

Urinary stones often affect younger people. Because the risk of recurrence is high, regular follow-up is important for individuals at risk.

OBJECTIVE

To summarize the extent of urinary stones and the health and economic impact in the population; to provide recommendations for general and stone-specific follow-up.

MATERIALS AND METHODS

Analysis and discussion of publications and guideline recommendations.

RESULTS

The risk of recurrence after a stone attack can be high depending on the risk profile. An initial metabolic workup should be performed promptly after stone therapy. General dietary management should be intensified by stone-specific dietary management depending on the risk profile. Nutritional counseling may be helpful. Imaging after stone therapy is used to monitor the success of treatment and detect recurrences early. Since the risk of recurrence can vary greatly depending on the stone composition, not only the type of imaging but also its frequency should be adjusted accordingly. The same applies to the various stone therapies, which help determine the frequency and type of imaging follow-up. Exact guidelines and cost-effectiveness analyses of follow-up examinations after stone therapy are unfortunately missing.

CONCLUSIONS

Acute urolithiasis represents an excruciating experience for patients. Accordingly, their willingness to undergo metaphylaxis and follow-up shortly after the event is strong. Since the risk of recurrence after a stone attack can be very high, regular follow-up after stone therapy is essential. The frequency of follow-up should be adapted to the probability of stone recurrence.

Acupuncture versus Lornoxicam in the Treatment of Acute Renal Colic: A Randomized Controlled Trial

Objective

To compare the analgesic efficacy and safety of acupuncture and lornoxicam in acute renal colic (ARC).

Design, Setting, Participant

A randomized, double-blind, parallel-controlled, single-centered trial was conducted at Susong County People’s Hospital from October 2019 to November 2020. Eighty-four patients with ARC were randomly divided into lornoxicam group (Group L) and acupuncture group (Group A). Group A was treated with acupuncture at Sanyinjiao (SP6), Yinlingquan (SP9) and normal saline, and Group L was treated with sham acupuncture at SP6, SP9 and lornoxicam.

Main Outcome Measures

Visual analogue scale (VAS) scores and adverse reactions such as nausea and dizziness were recorded within 5, 10, 15, 20 and 40 minutes after treatment. The main outcome of this study was the short-term effective (STE) rate, the secondary outcome was the onset time, and the safety index was incidence of adverse reactions.

Results

A total of 80 patients completed this study, including 41 patients (21 males and 20 females) in Group L and 39 patients (21 males and 18 females) in Group A. Group A exhibited lower scores versus group L after treatment (P < 0.05). The overall STE of group L was 61.00% (25/41), significantly lower than group A [84.62% (33/39)] (P < 0.001). There was no difference in the incidence of adverse reactions between group A [2.6% (1/39)] and group L [7.3% (3/41)] (P = 0.616). The ordered logistic regression analysis showed patients receiving acupuncture therapy are more likely to be cured [OR = 2.887, 95% CI: (1.190, 7.000), P = 0.019].

Conclusion

Acupuncture at SP6, SP9 and intramuscular injection of lornoxicam can effectively and safely relieve ARC, but the former has faster and better analgesic effect. Moreover, the incidence of adverse reactions was similar between the two treatments. This acupuncture therapy is recommended as a complementary therapy for ARC.

Opioid Analgesics and Persistent Pain After an Acute Pain Emergency Department Visit: Evidence from a Cohort of Suspected Urolithiasis Patients

BACKGROUND

Severe acute pain is still commonly treated with opioid analgesics in the United States, but this practice could prolong the duration of pain.

OBJECTIVES

Estimate the risk of experiencing persistent pain after opioid analgesic use after emergency department (ED) discharge among patients with suspected urolithiasis.

METHODS

We analyzed data collected for a longitudinal, multicenter clinical trial of ED patients with suspected urolithiasis. We constructed multilevel models to estimate the odds ratios (ORs) of reporting pain at 3, 7, 30, or 90 days after ED discharge, using multiple imputation to account for missing outcome data. We controlled for clinical, demographic, and institutional factors and used weighting to account for the propensity to be prescribed an opioid analgesic at ED discharge.

RESULTS

Among 2413 adult ED patients with suspected urolithiasis, 62% reported persistent pain 3 days after discharge. Participants prescribed an opioid analgesic at discharge were OR 2.51 (95% confidence interval [CI] 1.82-3.46) more likely to report persistent pain than those without a prescription. Those who reported using opioid analgesics 3 days after discharge were OR 2.24 (95% CI 1.77-2.84) more likely to report pain at day 7 than those not using opioid analgesics at day 3, and those using opioid analgesics at day 30 had OR 3.25 (95% CI 1.96-5.40) greater odds of pain at day 90.

CONCLUSIONS

Opioid analgesic prescription doubled the odds of persistent pain among ED patients with suspected urolithiasis. Limiting opioid analgesic prescribing at ED discharge for these patients might prevent persistent pain in addition to limiting access to these medications.

The prospective evaluation of the effectiveness of scoring systems in the emergency department in cases with suspected ureteral stones: STONE? CHOKAI?

INTRODUCTION

This study evaluates the effectiveness of CHOKAI and STONE scores in patients presenting to the emergency department with ureteral stones.

METHODS

Patients over the age of 18 who were admitted to the emergency department with flank pain, groin pain, scrotal pain, and hematuria and who were performed non-contrast abdominal computed tomography (CT) for diagnostic imaging were included. The numeric pain, CHOKAI, and STONE scores of the patients were calculated. The effectiveness of these scoring systems in the presence of stones was examined.

RESULTS

A total of 105 patients were included in the study. In the analysis performed to investigate whether there was a difference between the numeric pain, STONE, and CHOKAI scores in terms of the presence of stones on CT, it was seen that the CHOKAI score was significantly different from the others (p < 0.001). A significant positive correlation was found between the CHOKAI score and stone size (r = 0.343, p < 0.001).When the cut-off value of the CHOKAI score was >7, the sensitivity was found to be 60.49%, and specificity was 83.33%. The cut-off value for the STONE score was >8 with a sensitivity of 70.37% and specificity of 58.33%. The corresponding area under curve values for the CHOHAI and STONE scores was 0.788 (p < 0.0001) and 0.615 (p = 0.087). Male sex, the CHOKAI, and STONE scores were the independent risk factors for ureteral stone. A significant positive correlation was found between the CHOKAI score and stone size (r = 0.343, p < 0.001).

CONCLUSION

The CHOKAI score has a higher performance than the STONE score in detecting the presence of ureteral stones.

NEW KNOWLEDGE ADDED BY THIS STUDY

The CHOKAI score has a higher performance than the STONE score in detecting the presence of ureteral stones. Especially in countries such as Turkey, where there are no specific racial differences, the STONE score may be diagnostically insufficient. The CHOKAI score shows the presence of the patient's stone and positively correlates with the size of the stone and the stone location.

IMPLICATION FOR CLINICAL PRACTICE OR POLICY

In the functioning of the emergency department, it is important to make the differential diagnosis of patients quickly and provide effective treatment. The use of diagnostic scoring systems saves time for the emergency physician in the differential diagnosis phase and guides in terms of applying for possible additional imaging methods.

Minimally Invasive Surgery for the Treatment of Ureteric Stones - State-of-the-Art Review

The landscape of managing ureteric stones has evolved over the last few decades and several treatment options exist depending on the stone size, location, and other patient and stone factors. While open surgery is now rarely performed, the use of medical expulsive therapy (MET) has been controversial and perhaps only recommended for large distal ureteric stones. The mainstay treatment balances between shockwave lithotripsy (SWL) and ureteroscopy (URS), with the latter usually recommended for larger stones. While the principles of ureteric stone management have remained largely unchanged, the modern era has generated new methods and means to deliver it. Advancements have occurred in all domains of endourology to try and refine treatment and balance it with cost, patient choice and quality of life. Dissemination of technologies and demonstration of their efficacy and safety will eventually result in new recommendations among international guidelines and evolution of new gold standards.

Role of conservative management of stones

Urinary tract stone disease is one of the most common pathologies of the modern era with a rising prevalence owing to incidentally detected renal stones from imaging for other reasons. Although there is consensus on active management of symptomatic and asymptomatic stones in high-risk patient groups, conservative management of stones is still controversial. We have reviewed the literature pertaining to conservative management of 3 groups of stones-asymptomatic calyceal stones, staghorn stones, and ureteric stones-and summarized the findings to provide guidance in the conservative management of stones. In the calyceal stone group, our review showed an average spontaneous stone passage rate of 18% (range, 8%-32%) and an average requirement for surgical intervention of 20% (range, 7%-40%), with 62% of patients remaining safely on surveillance over a mean time of 4 years. In the staghorn group, overall disease-specific mortality was noted to be 16% (range, 0%-30%) and chance of renal deterioration was 21% (range, 0%-34.5%), with a mean incidence of infection of 22%. In case of conservatively managed ureteric stones, the rate of spontaneous passage for stones smaller than 5 mm was 75%, compared with 62% for those larger than 5 mm. Based on the position in the ureter, spontaneous passage rates were 49%, 58%, and 68% for proximal, middle, and distal thirds, respectively. Conservative management may be recommended for asymptomatic patients and those who are deemed unfit for any procedures. However, careful patient selection and thorough counseling about the risks of conservative management could make it a suitable option for an appropriate subset of patients.

Fragmentation and propulsive effect of shock wave lithotripsy in treatment of small renal calculi

Background

Small renal calculi are frequently observed in clinical practice, and chemo-lytic therapy has limited effects. The purpose of the study is to evaluate the effectiveness of extracorporeal shock wave lithotripsy (ESWL) in the treatment of small renal calculi.

Methods

We studied 60 patients with small renal stones from March 2017 to March 2019. After excluding eight patients with incomplete data, the remaining 52 patients were evaluated. Patients with symptomatic single or multiple stones of 6–8 mm in diameter or asymptomatic on ultrasound and kidney-ureter-bladder radiograph were eligible for inclusion. Small stones were treated by ESWL. The data were analyzed using the Statistical Packages for Social Sciences - version 25 (IBM Corporation).

Results

The mean age of the 52 patients was 34.5 ± 9.5 years. Forty-one (78.8%) patients were symptomatic, while 11 (21.2%) were asymptomatic. Forty-seven (90.4%) had single small renal stones, while four patients had two stones (7.7%) and only one patient had three stones (1.9%). Forty-five stones were successfully treated by ESWL, while 13 stones failed to respond.

Conclusion

ESWL is a useful tool for treating small renal calculi; it works either by fragmenting the stones or by acting as a pushing force. However, further large prospective studies are needed to corroborate the above conclusions.

Development and validation of a score for emergency intervention in patients with acute renal colic secondary to ureteric stones

Objectives: To develop and validate a scoring system to assess the need for emergency intervention (EI) in patients with uncomplicated acute renal colic (ARC) due to ureteric stones. Patients and methods: From May 2017 to April 2019, 382 adult patients presented to emergency department with ARC due to ureteral stones diagnosed by non-contrast computed tomography. Patients with solitary kidney, complications secondary to obstruction (intractable vomiting, fever or sepsis), bilateral ureteric stones, Stage ≥3 chronic kidney disease or those who underwent treatment of urolithiasis within the past 6 months were excluded. EI was performed in cases with persistent or recurrent pain despite analgesics. Multivariate analysis was performed for the first 200 patients to detect risk factors for EI. The score was developed from significant factors. Sensitivity and specificity of the ARC score were calculated using receiver operator characteristic (ROC) curve analysis. The data of last 182 patients were used for validation of the score. Results: In the first 200 patients, EI was needed in 119 patients (59.5%) and included ureteric stents in 92, ureteroscopy in 25 and percutaneous nephrostomy in two. Significant factors for EI were stone location (relative risk [RR] 3.34, P = 0.026), creatinine level (RR 1.04, P < 0.001), leucocyte count (RR 1.69, P < 0.001), and stone length (RR 1.85, P < 0.001). A score using these four variables was developed. The ARC score sensitivity was 86%, specificity was 80% and the area under the ROC curve was 0.902. Validation of the score showed strong correlation between ARC score and need for EI (r = 0.788, P < 0.001). Conclusions: The ARC score is a validated, highly sensitive and specific novel score to determine the need for EI in patients with uncomplicated ARC secondary to ureteric stones. Abbreviations: ARC: acute renal colic; AUC: area under the ROC curve; CDR: clinical decision rules; CKD: chronic kidney disease; ED: emergency department; EI: emergency intervention; MET: medical expulsive therapy; NCCT: non-contrast CT; PCNL, percutaneous nephrolithotomy; ROC: receiver operator characteristic; S.T.O.N.E.: stone size (S), tract length (T), obstruction (O), number of involved calyces (N), and essence or stone density (E); SWL: extracorporeal shockwave lithotripsy; URS: ureteroscopy; WBC: white blood cell.

Association of Severe Microscopic Hematuria with Successful Conservative Treatment of Single Uncomplicated Ureteral Calculus: A Multicenter Cohort Study

BACKGROUND

Although detection of microscopic hematuria is a well-known diagnostic method for urolithiasis, its ability to predict urolithiasis treatment outcomes in adults is unknown.

OBJECTIVE

To evaluate the role of microscopic hematuria in conservative treatment of ureteral calculus.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study involved 482 patients who were diagnosed with a single uncomplicated ureteral calculus (≤10 mm) using computed tomography and underwent conservative therapy at two Japanese community hospitals between 2013 and 2018. Patients were divided into three groups according to the severity of microscopic hematuria (no, ≤4; mild to moderate, 5-99; and severe, ≥100 red blood cells per high-power field) and as determined during the first emergency department or urologic outpatient clinic visit.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

A multivariate logistic regression analysis was performed to estimate the odds ratio for successful conservative therapy at 28 d after the diagnosis. Statistical significance was set at p < 0.05.

RESULTS AND LIMITATIONS

Of the 482 patients, 81 (16.8%), 209 (43.4%), and 192 (39.8%) had no, mild to moderate, and severe microscopic hematuria, respectively. After adjustments for six relevant confounders, severe microscopic hematuria showed a significant association with successful conservative therapy at 28 d (adjusted odds ratio, 1.91; 95% confidence interval, 1.02-3.57; p = 0.043), whereas mild to moderate microscopic hematuria did not (adjusted odds ratio, 1.05; 95% confidence interval, 0.57-1.93; p = 0.872) when compared with no microscopic hematuria.

CONCLUSIONS

Severe microscopic hematuria was significantly associated with successful conservative therapy for single uncomplicated ureteral calculus.

PATIENT SUMMARY

Microscopic hematuria might have predictive value for conservative treatment of a single uncomplicated ureteral calculus. Using the presence or absence of blood in urine and other predictive factors, clinicians may lead patients with a single uncomplicated ureteral calculus to successful conservative therapy.

'Negative Ureteroscopy' for Stone Disease: Evidence from a Systematic Review

PURPOSE OF REVIEW

While ureteroscopy (URS) is a common procedure for ureteric stones, this window between diagnosis and treatment leaves the possibility for a 'negative', 'stoneless' or 'diagnostic' URS. We perform a systematic review to look at the rate of 'negative ureteroscopy' and risk factors associated with it.

RECENT FINDINGS

From a total of 3599 articles and 68 abstracts, 4 studies (1336 patients) were selected. The negative URS rate varied from 4 to 14%. Common predictors seem to be female gender, small stones, radiolucent stones and distal ureteric stones. Although infrequent, negative ureteroscopy should be avoided in patients with ureteric stones by performing a low-dose CT scan on the day of surgery. This should especially be performed for females and those with smaller, radiolucent or distal ureteric stones.