Time to stone passage for observed ureteral calculi: a guide for patient education

Role of the systemic immune-inflammation index in predicting spontaneous stone passage in patients with renal colic

OBJECTIVES

Renal colic (RC) is one of the most frequent reasons for presentation to the emergency department (ED) and creates a high economic and medical burden. Management strategies for RC range from waiting for spontaneous passage to surgical intervention. However, factors determining spontaneous stone passage (SSP) are still poorly understood. Therefore, in this study, we aimed to investigate the role of the systemic immune-inflammatory index (SII) in predicting SSP.

METHODS

We retrospectively analyzed the data of 924 patients aged over 18 years, who were diagnosed with RC in our clinic between 1 January 2019, and 30 May 2022, and had ureteral stones of ≤ 10 mm. The patients were divided into two groups according to whether they had SSP. The clinical and laboratory characteristics of the patients in the ED were evaluated. The neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and SII (neutrophil count x platelet count/lymphocyte count) values of the patients were calculated. Stone size and location were also recorded.

RESULTS

In the univariate analysis of SSP, a ureteral stone size of ≤ 5 mm (p < 0.001), distal ureteral location (p < 0.001), SII (p < 0.001), NLR (p < 0.001), and PLR (p = 0.036) were significantly correlated with SSP. ROC analysis showed that an SII level < 721.8 (Sensitivity %82.6, Specificity %74.7, p < 0.001) was an independent predictor of SSP.

CONCLUSION

Our findings showed that a low SII level was associated with SSP and could be used as a predictive marker of SSP as a more valuable parameter than NLR. SII and NLR, together with other indicators, are inflammatory markers that can be used in the clinical decision-making process for ureteral stone treatment.

Optimal duration of medical expulsive therapy for lower ureteral stones: a critical evaluation

To evaluate the optimal duration of Medical Expulsive Therapy (MET) application for distal ureteric stones on a time period based manner. 89 patients with 5-10 mm distal ureter stones received tamsulosin (0.4 mg) for MET and diclofenac sodium (75 mg) for analgesia. Patients were evaluated once a week for 4 weeks. Radiologic stone passage was evaluated by kidney ureter bladder (KUB) and ultasonography where non-contrast computed tomography (NCCT) was also performed if needed. While 23 cases (28.4%) were SF after first week, 23 were SF (28.4%) after 2 weeks, 9 cases (11.1%) after 3 and lastly 7 cases (8.6%) became SF after four weeks. Nineteen (23.5%) cases were not SF after 4 weeks. A positive relationship was found between the time period elapsed for stone passage and ureteral wall thickness (UWT) along with the degree of hydronephrosis. In addition, mean number of renal colics and emergency department (ED) visits were found to be higher in patients passing stones in the 4th week along with the ones who could not despite MET. SFR for distal ureteric stones sizing 5-10 mm was higher within the first 3 weeks under MET application. Thus, waiting for a longer period of time may result in increased analgesic and unnecessary MET treatment with increased risk of emergency department visits and additional costs as well. We believe that other options could be considered in such cases who are not SF at the end of the first 3 weeks.

Inhibition of PDE-4 isoenzyme attenuates frequency and overall contractility of agonist-evoked ureteral phasic contractions

The aim of this study was to investigate the functional role of phosphodiesterase enzymes (PDE) in the isolated porcine ureter. Distal ureteral strips were mounted in organ baths and pre-contracted with 5-HT (100 μM). Upon generation of stable phasic contractions, PDE-4 and PDE-5 inhibitors were added cumulatively to separate tissues. PDE-4 inhibitors, such as rolipram (10 nM and greater) and roflumilast (100 nM and greater), resulted in significant attenuation of ureteral contractile responses, while a higher concentration of piclamilast (1 μM and greater) was required to induce a significant depressant effect. The attenuation effect by rolipram was abolished by SQ22536 (100 μM). PDE-5 inhibitors, such as sildenafil and tadalafil, were not nearly as effective and were only able to suppress the 5-HT-induced contractions at higher concentrations of 1 μM. Rolipram significantly enhanced the depressant effect of forskolin, while sodium nitroprusside-induced attenuation of contractile responses remained unchanged in the presence of tadalafil. In summary, our study demonstrates that PDE-4 inhibitors are effective in attenuating 5-HT-induced contractility in porcine distal ureteral tissues, while PDE-5 inhibitors are less effective. These findings suggest that PDE-4 inhibitors, such as rolipram, may hold promise as potential therapeutic agents for the treatment of ureteral disorders attributable to increased intra-ureteral pressure.

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.

Percutaneous nephrolithotomy versus retrograde intrarenal surgery for treatment of renal stones in adults

BACKGROUND

Kidney stones (also called renal stones) can be a source of pain, obstruction, and infection. Depending on size, location, composition, and other patient factors, the treatment of kidney stones can involve observation, shock wave lithotripsy, retrograde intrarenal surgery (RIRS; i.e. ureteroscopic approaches), percutaneous nephrolithotomy (PCNL), or a combination of these approaches.

OBJECTIVES

To assess the effects of percutaneous nephrolithotomy (PCNL) versus retrograde intrarenal surgery (RIRS) for the treatment of renal stones in adults.

SEARCH METHODS

We performed a comprehensive search of the Cochrane Library, MEDLINE, Embase, Scopus, and two trials registries up to 23 March 2023. We applied no restrictions on publication language or status.

SELECTION CRITERIA

We included randomized controlled trials that evaluated PCNL (grouped by access size in French gauge [Fr] into three groups: ≥ 24 Fr [standard PCNL], 15-23 Fr [mini-PCNL and minimally invasive PCNL], and < 15 Fr [ultra-mini-, mini-micro-, super-mini-, and micro-PCNL]) versus RIRS.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies and extracted data from the included studies. Our primary outcomes were stone-free rate, major complications, and need for secondary interventions. Our main secondary outcomes were unplanned medical visits to emergency/urgent care or outpatient clinic, length of hospital stay, ureteral stricture or injury, and quality of life. We performed statistical analyses using a random-effects model. We rated the certainty of evidence using GRADE criteria. We adopted a minimally contextualized approach with predefined thresholds for minimal clinically important differences (MCIDs).

MAIN RESULTS

We included 42 trials assessing the effects of PCNL versus RIRS in 4571 randomized participants. Twenty-two studies were published as full-text articles, and 20 were published as abstract proceedings. The average size of stones ranged from 10.1 mm to 39.1 mm. Most studies did not report sources of funding or conflicts of interest. The main results for the most important outcomes are summarized below. Stone-free rate PCNL compared with RIRS may improve stone-free rates (risk ratio [RR] 1.13, 95% confidence interval [CI] 1.08 to 1.18; I2 = 71%; 39 studies, 4088 participants; low-certainty evidence). Based on 770 participants per 1000 being stone-free with RIRS, this corresponds to 100 more (62 more to 139 more) stone-free participants per 1000 with PCNL (an absolute difference of 10%, where the predefined MCID was 5%). Major complications PCNL compared with RIRS probably has little or no effect on major complications (RR 0.86, 95% CI 0.59 to 1.25; I2 = 15%; 34 studies, 3649 participants; moderate-certainty evidence). Based on 31 complications in the RIRS group, this corresponds to six fewer (13 fewer to six more) major complications per 1000 with PCNL (an absolute difference of 0.6%, where the predefined MCID was 2%). Need for secondary interventions PCNL compared with RIRS may reduce the need for secondary interventions (RR 0.31, 95% CI 0.17 to 0.55; I2 = 61%; 21 studies, 2005 participants; low-certainty evidence). Based on 222 secondary interventions in the RIRS group, this corresponds to 153 fewer (185 fewer to 100 fewer) secondary interventions per 1000 with PCNL (an absolute difference of 15.3%, where the predefined MCID was 5%). Unplanned medical visits No studies reported unplanned medical visits. Length of hospital stay PCNL compared with RIRS may extend length of hospital stay (mean difference 1.04 days more, 95% CI 0.27 more to 1.81 more; I2 = 100%; 26 studies, 2804 participants; low-certainty evidence). This effect size is greater than the predefined MCID of one day. Ureteral stricture or injury PCNL compared with RIRS may have little or no effect on the occurrence of ureteral strictures (RR 0.93, 95% CI 0.39 to 2.21; I2 = 0%; 13 studies, 1574 participants; low-certainty evidence). Based on 14 ureteral strictures in the RIRS group, this corresponds to one fewer (nine fewer to 17 more) ureteral strictures per 1000 with PCNL (an absolute difference of 0.1%, where the predefined MCID was 2%). Quality of life No studies reported quality of life.

AUTHORS' CONCLUSIONS

Based on a large body of evidence from 42 trials, we found that PCNL compared with RIRS may improve stone-free rates and may reduce the need for secondary interventions, but probably has little or no effect on major complications. PCNL compared with RIRS may have little or no effect on ureteral stricture rates and may increase length of hospital stay. We found no evidence on unplanned medical visits or participant quality of life. Because of the considerable shortcomings of the included trials, the evidence for most outcomes was of low certainty. Access size for PCNL was less than 24 Fr in most studies that provided this information. We expect the findings of this review to be helpful for shared decision-making about management choices for individuals with renal stones.

Effect of gender on presentation and outcome of renal colic

OBJECTIVES

To examine gender-related differences in the presentation, management, and outcomes of patients admitted to the emergency department ED with ureteral stones.

METHODS

Retrospective analysis of all patients admitted to the ED at our institution, found to have a ureteral stone on CT. Clinical, laboratory, imaging parameters, and outcomes were collected.

RESULTS

778 patients were admitted with ureteral stones between January 2018 and December 2020. 78% (n = 609) were males and 22% (n = 169) were females. The mean ages were 49.4 (SD 14.4) and 51.6 (SD 15.7) in males and females, respectively (p = 0.08). Female patients presented with a higher body temperature (p = 0.01), pulse rate (p < 0.0001), nausea and vomiting (p < 0.0001), elevated serum C-reactive protein (CRP) (p = 0.002) compared to males. The prevalence of elevated serum creatinine was higher in males (p < 0.0001). Alpha-blockers were recommended on discharge in 54.8% (334) of males, compared to only 29.6% (50) of females (p < 0.0001). Spontaneous stone expulsion was significantly higher in males compared to females (p = 0.01).

CONCLUSIONS

Our results demonstrate that gender does effect presentation and outcome of patients presenting with renal colic. Females were found to have elevated infectious parameters, more nausea and vomiting and a higher incidence of positive urine cultures. Males admitted to the ED were found to have significantly higher serum creatinine levels. Medical expulsive therapy (MET) with alpha-blockers was prescribed significantly less in female patients, which may have resulted in a lower spontaneous stone expulsion rate.

The Rho-kinase inhibitor Y27632 promotes ureteral relaxation in an in vivo rat model for partial ureteral obstruction

PURPOSE

Aim of this study was to evaluate the effect of intravenous Y27632 (a ROK inhibitor) on intra-ureteral pressures and on blood pressure in an in vivo rat model for unilateral partial ureteral obstruction (PUO).

METHODS

15 Male Sprague Dawley rats were used. Under isofluran anesthesia, saline was continuously infused via polyethylene (PE)-10 catheters inserted in the ureters beneath the kidney pelvis. Left psoas muscle was sutured around the distal left ureter to create a partial obstruction. Carotid artery and femoral vein were cannulated with PE catheters for registration of mean arterial blood pressure (MAP) and for administration of drugs. Left and right ureter pressures and MAP were simultaneously recorded. Y27632 (0.03 and 0.1 mg/kg each n = 6-7) was given intravenously. T-test was used for comparisons.

RESULTS

Spontaneous peristaltic pressure waves were recorded at baseline for both ureters. After the obstruction, Y27632 reduced maximum pressure (MaxP) by 10.5 ± 1.9% (0.03 mg/kg; p = 0.004) and 29.1 ± 4.8% (0.1 mg/kg; p < 0.001), minimum pressure (MinP) by 5.2 ± 2.3% (0.03 mg/kg; p = 0.02) and 12.2 ± 3.4% (0.1 mg/kg; p = 0.009), the area under the curve (AUC) by 7.8 ± 2.4% (0.03 mg/kg; p = 0.008) and 16.5 ± 3.7% (0.1 mg/kg;p = 0.007), the waves amplitude by 23.4 ± 11.3% (0.03 mg/kg; p = 0.098) and 38.7 ± 7.5% (0.1 mg/kg; p < 0.001), with no effect on contraction frequency. During simultaneous recordings from the normal ureter at the investigated doses, Y27632 reduced MaxP, MinP, AUC and waves amplitude by 1-7%. The MAP was reduced by 12.5 ± 5.3% (0.03 mg/kg; p = 0.07) and 15.8 ± 1.8% (0.1 mg/kg; p < 0.001).

CONCLUSIONS

Y27632 decreased intra-ureteral pressures of a partially obstructed ureter with limited effect on blood pressure in an animal model of unilateral PUO.

Urinoma Due to Spontaneous Rupture of the Renal Pelvis Mimicking Appendicitis

Spontaneous rupture of the renal pelvis (SRRP) with urine extravasation is rare. This condition is primarily associated with an obstructing ureteric calculus. It creates a diagnostic dilemma, especially when the clinical diagnosis can be inconsistent. Herein, we report a 49-year-old male patient who presented with abdominal pain for the past three days and was diagnosed with acute appendicitis. A computed tomography (CT) scan revealed a right renal pelvis rupture and urinoma secondary to an obstructive 4 mm ureterovesical junction calculi. The patient was successfully treated with double-J stent placement. In conclusion, even though SRRP is rare, emergency physicians should have knowledge regarding this condition, which often presents as an abdominal condition and may be misdiagnosed as another condition requiring surgical intervention. Radiologic investigations such as CT scans are useful methods in suspected cases of this condition in order to reduce unnecessary surgical intervention.

Medical Expulsive Therapy for Pediatric Ureteral Stones: A Meta-Analysis of Randomized Clinical Trials

To evaluate the efficacy and safety of medical expulsive therapy (MET) for ureteral stones in pediatric patients, Cochrane, PubMed, Web of Science, Scopus, and the reference list of retrieved studies were searched up to September 2022 to identify RCTs on the efficacy of MET. The protocol was prospectively registered at PROSPERO (CRD42022339093). Articles were reviewed, data were extracted by two reviewers, and the differences were resolved by the third reviewer. The risk of bias was assessed using the RoB2. The outcomes, including the stone expulsion rate (SER), stone expulsion time (SET), episode of pain, analgesic consumption, and adverse effects, were evaluated. Six RCTs enrolling 415 patients were included in the meta-analysis. The duration of MET ranged from 19 to 28 days. The investigated medications included tamsulosin, silodosin, and doxazosin. The stone-free rate after 4 weeks in the MET group was 1.42 times that of the control group (RR: 1.42; 95% CI: 1.26-1.61, p < 0.001). The stone expulsion time also decreased by an average of 5.18 days (95% CI: -8.46/-1.89, p = 0.002). Adverse effects were more commonly observed in the MET group (RR: 2.18; 95% CI: 1.28-3.69, p = 0.004). The subgroup analysis evaluating the influence of the type of medication, the stone size, and the age of patients failed to reveal any impact of the aforementioned factors on the stone expulsion rate or stone expulsion time. Alpha-blockers as medical expulsive therapy among pediatric patients are efficient and safe. They increase the stone expulsion rate and decrease the stone expulsion time; however, this included a higher rate of adverse effects, which include headache, dizziness, or nasal congestion.

Software-Estimated Stone Volume Is Better Predictor of Spontaneous Passage for Acute Nephrolithiasis

Purpose: To evaluate whether computer program-estimated urolith stone volume (SV) was a better predictor of spontaneous passage (SP) compared with program-estimated stone diameter (PD) or manually measured stone diameter (MD), and whether utilizing SV and MD together provided additional value in SP prediction compared with MD alone. Materials and Methods: Retrospective analysis of patients with acute renal colic and single renal/ureteral stone on CT from July 2017 to April 2020. Diameter obtained from radiology reports or manually measured when report not available. Semiautomated stone analysis software (qSAS) was used to estimate SV and PD. ROC analysis was performed to compare accuracy of SV vs MD vs PD in predicting SP by 2, 4, and 6 weeks. Subgroup analysis was performed by stone size ( Collapse

Key Words

• CT
• nephrolithiasis
• renal colic
• stone passage
• stone volume

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MESH Headings

• Humans
• Retrospective Studies
• Prospective Studies
• Remission, Spontaneous
• Ureteral Calculi/diagnostic imaging
• Kidney Calculi
• Software

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Affiliation(s)

Tommy Chiou Department of Urology, University of California San Diego, San Diego, California, USA
Margaret F. Meagher Department of Urology, University of California San Diego, San Diego, California, USA
Jonathan H. Berger Department of Urology, University of California San Diego, San Diego, California, USA
Tony T. Chen Department of Urology, University of California San Diego, San Diego, California, USA
Roger L. Sur Department of Urology, University of California San Diego, San Diego, California, USA
Seth K. Bechis Department of Urology, University of California San Diego, San Diego, California, USA

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Effect of α1D-adrenoceptor blocker for the reduction of ureteral contractions

PURPOSE

Urolithiasis is a common urinary tract disease with growing prevalence. Alpha1-adrenoceptors (α1-ARs) are abundant in ureteral smooth muscle, distributed with different α1-AR subtypes. α1D-AR is the most widely distributed in the ureter. However, the effect of α1D-AR blockade on ureteric contraction remains unknown.

MATERIALS AND METHODS

We dissected smooth muscle tissues (3 mm×3 mm) from the rat bladder and human ureter, tied silk strips on both tissue ends, and measured contraction in an organ bath chamber. Contraction activity in ureteral smooth muscle cells (USMCs) was immunocytochemically examined using primary rat and human USMC cultures.

RESULTS

Using the organ bath system, we determined the inhibitory effects of silodosin, tamsulosin, and naftopidil. Naftopidil significantly decreased contractility of rat bladder tissue; similar results were observed in human ureteral tissue. To confirm ex vivo experimental results in vitro , we examined the phosphorylation of myosin light chain (MLC), a marker of contractility, in a primary human USMC culture. The examined drugs decreased phospho-MLC levels in human USMCs; however, naftopidil profoundly increased MLC dephosphorylation.

CONCLUSIONS

We studied the effects of naftopidil, an α1D-AR inhibitor, on the ureter. Compared with alpha-blockers, naftopidil significantly relaxed ureteral smooth muscle. Therefore, naftopidil could be an effective therapy for patients with ureteral stones.

Management of pediatric ureterolithiasis in the emergency room: A single institution review and new management pathway

INTRODUCTION/BACKGROUND

Urolithiasis is an increasingly common condition seen in children with an annual incidence of 2-3% in children under 18, and up to 10% in adolescents. Treatment of stones varies including observation, IV hydration, pain management, medical expulsive therapy (MET), or surgery. Though well-studied and often used in adults, MET (alpha-adrenergic antagonists to facilitate passage of ureteral stones), is not routinely prescribed in pediatric patients.

OBJECTIVE

The goals of this study were to review a quaternary children's hospital's emergency room frequency of MET utilization for ureterolithiasis as well as evaluate the clinical outcomes of children who were prescribed MET compared to those treated with pain control alone.

STUDY DESIGN

A retrospective review was performed of children 2 months to 18 years with ureterolithiasis who presented to a quaternary children's hospital ED from 2011 to 2017. The primary outcome was the frequency of MET prescribed. Secondary outcomes included the following comparisons in patients who received MET and analgesics with those who received analgesics alone: hospital admission rate, length of hospitalization, emergency room re-presentation rate, surgical intervention, spontaneous stone passage, urology consultation, how the urology consult affected MET utilization, referral to outpatient urology and nephrology clinics, and CT utilization in the ED. Comparisons were performed utilizing Fischer's exact and t-tests.

RESULTS

139 patients were included with a mean age of 14 years (SD 4.14), 42% male. There was no difference between age, gender, stone size, return to the ED, serum creatinine, or length of hospitalization (if admitted) between patients who were and were not placed on MET. The rate of stone passage was significantly higher for those placed on MET (45%) versus not (20%) (p = 0.0022). Urology was consulted for 93% of the cases where children were prescribed MET, compared with only 52% of cases where MET was not prescribed (p = <0.0001).

DISCUSSION

In our experience MET was significantly underutilized in patients where urology was not involved. This is similar to a study by Itano et al. which found urology consultation in the ED significantly increased use of tamsulosin for ureterolithiasis in adults. Children with ureterolithiasis placed on MET had a significantly higher rate of stone passage compared to children managed by pain control alone.

CONCLUSION

Given the benefits of MET to increase the rate of spontaneous stone passage it may be considered first line therapy for treatment of children with ureterolithiasis.

Spontaneous stone expulsion in patients with history of urolithiasis

Objectives:

To examine differences in the presentation, management, and outcomes of patients admitted to the emergency department (ED) with ureteral stones, with prior history of urolithiasis compared to patients with a first stone event.

Patients and Methods:

Retrospective analysis of patients who visited the ED that were found to have a ureteral stone on CT. Patients were stratified into two groups: without history of urolithiasis (Group 1) and with history of urolithiasis (Group 2).

Results:

Between 2018 and 2020, 778 patients were admitted with ureteral stones. Patients in group 1 presented with a higher mean serum creatinine ( p = 0.02), larger mean stone size ( p < 0.0001), and a higher proportion of proximal ureteral stones ( p < 0.0001) than patients in group 2. The 30 day readmission rate was significantly higher in group 1 ( p = 0.02). Spontaneous stone expulsion was higher in group 2 ( p < 0.0001), whereas the need for endourological procedures was higher in group 1 ( p < 0.0001). On multivariable analysis serum creatinine (OR 0.264, 95% CI 0.091–0.769, p = 0.01) and stone size (OR 0.623, 95% CI 0.503–0.771, p < 0.0001) were associated with a lower spontaneous stone expulsion rate. History of prior endourological procedures (OR 0.225, OR 0.066–0.765, p = 0.01) was associated with a higher spontaneous stone expulsion rate.

Conclusions:

Our data suggests that patients who are first time stone formers present with larger and more proximal ureteral stones, with a lower likelihood of spontaneous stone expulsion and a subsequent need for surgical intervention. Previous stone surgery and not previous stone expulsion was found to be a predictor for spontaneous stone passage.

Trends of Acute Renal Colic During COVID-19 Lockdown: An Experience From Saudi Arabia

Introduction

The COVID-19 pandemic represents an unprecedented challenge for healthcare systems around the world. Saudi Arabia was one of the first countries to experience a lockdown and postponement of elective surgical procedures. The objective of this study was to assess the trends of acute renal colic presenting to our emergency department.

Methods

This retrospective study targeted all patients who presented with acute renal colic during the lockdown period (March 23, 2019 to June 20, 2019). Patients’ and stone data were collected. The patient’s data included age, gender, BMI, and comorbidities. Stones' data included stone size, location, side, evidence of obstruction and UTI, and planned and conducted management.

Results

A total of 137 patients were identified; 92 (67.2%) patients were males with a mean age of 44 ± 16 years. Positive history of urolithiasis was reported in 47 (34.3%). The most common initial investigation was non-contrast CTs (93.4%). The majority of patients had a stone size of < 10 mm (93%) and ureteric stones (81.2%). A total of 32 patients (32.4%) had evidence of UTI and 63.4% had evidence of obstruction. Most of the patients (73.7%) were offered medical expulsive therapy (MET). Only 2.2% did not receive the planned management.

Conclusion

The observed pattern shows that the management during the lockdown did not differ from the original recommendations. This could be due to the fact that most patients had stone sizes between 5 and 10 mm and consequently were managed by METs. Larger data need to be conducted to provide concrete evidence. Such data are relevant to provide a clear guide for management and to establish protocols for emergency lockdown situations.

Effect of age on presentation and outcome in renal colic

Objectives:

To examine the age-related differences in the presentation, management, and outcomes of patients admitted to the emergency department (ED) with ureteral stones.

Patients and methods:

A retrospective analysis of all patients who visited the ED at a single institution that were found to have a ureteral stone on CT. Clinical, laboratory, and imaging parameters were collected, including outcomes. Patients were subdivided into age groups: 18–30, 31–50, 51–70, and >70 years.

Results:

Between January 2018 and December 2020, 778 patients were admitted to the ED with a ureteral stone. About 78% (609) were males and 22% (169) were females. The mean ages were 49.4 (SD 14.4) and 51.6 (SD 15.7) in males and females, respectively ( p = 0.08). Patients in the 36–50 age group, had significantly higher visual analogue scale (VAS) scores ( p < 0.0001). Patients older than 70 years old presented with significantly higher serum creatinine levels ( p < 0.0001), C-reactive protein (CRP) ( p < 0.001) and leukocyte levels ( p = 0.002). These patients were also found to have significantly larger stones (mean size of 6.2 mm (SD 4.8) ( p < 0.0001)) and underwent percutaneous nephrolithotripsy (PCNL) in significantly higher numbers (56.3% vs 43.8%, ( p < 0.0001)). Less than half of the patients older than 50 years were given medical expulsive therapy (MET) with alpha-blockers, compared to more than 50% in the other age groups ( p = 0.002). Spontaneous stone expulsion was noted in 70.2% of the 18–35-year group, 62.4% of the 36–50-year-old group, 51.8% of the 51–70-year-old group, and 37% of the >70-year-old group ( p < 0.0001). The ED re-admission rates at 7 and 30 days were not significantly different among all age groups.

Conclusions:

Our data suggests that older patients presented with larger stones, elevated inflammatory markers and creatinine and were more likely to require surgical intervention. The spontaneous stone expulsion rate was inversely associated with age.

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.

Rising prevalence of renal calculi: Treatments and considerations

ABSTRACT

Severe pain and urinary tract obstruction are hallmarks of renal calculi often requiring hospitalization and treatment. Renal damage can occur without proper intervention. This article discusses the role of nurses in caring for patients with renal calculi, current treatment approaches, and prevention strategies.

EFFICACY OF DOXAZOSIN VERSUS TAMSULOSIN IN LOWER URETERIC STONE EXPULSION IN ADULT POPULATION OF DISTRICT DERA ISMAIL KHAN, PAKISTAN

Background: Urolithiasis is the third common disease of the urinary tract after UTIs and pathological diseases of the prostate. The objective of this study was to compare the efficacy of doxazosin versus tamsulosin in lower ureteric stone expulsion in adult population of District Dera Ismail Khan, Pakistan.Materials Methods: This non-randomized control trial was conducted in the Department of Urology, Gomal Medical College, Dera Ismail Khan, Pakistan from February 2020 to December 2020. The 252 patients included in our study were divided in to two groups. The patients in experimental group received Tab. doxazosin 4 mg daily for 4 weeks and Tab. diclofenac sodium 50 mg B.D for 5 days and then on need basis. The patients in control group received Cap. tamsulosin 0.4 mg daily for 4 weeks and similarly Tab. diclofenac sodium 50 mg as in experimental group. All the patients were followed regularly for expulsion of ureteric stones for four weeks. Sex, age and stone size were matching, while stone expulsion was a research variable. Hypothesis was verified by McNemar chi-square test.Results: Out of 252 patients, 113 (89.68%) patients in experimental group, while 77 (61.11%) patients in control group passed the stones. There was statistically significant difference in efficacy in doxazosin group as compared to tamsulosin group (p-value=.0001).Conclusion: The use of doxazosin as the medical expulsion therapy for the lower ureteric stone proved to be more effective as compared to tamsulosin as demonstrated by our results.

EFFICACY OF ALFUZOSIN VERSUS CONTROL GROUP IN UPPER URETERIC STONE EXPULSION IN ADULT POPULATION OF LAHORE, PAKISTAN

Background: Urinary stone disease is one of the commonest urological diseases worldwide. The objective of this study was to compare the efficacy of alfuzosin versus control group in upper ureteric stone expulsion in adult population of district Lahore, Pakistan.Materials Methods: This trial was conducted in Department of Urology, Sheikh Zayed Hospital, Lahore, Pakistan form January 2017 to June 2017. All adult patients with upper ureteric stone size 5-10 mm were eligible. Those with multiple stones, having fever, severe pain, history of surgery in past two weeks and growth on urine culture or pyuria were excluded. Experimental and control groups each had 30 patients. Experimental group received Tab. alfuzosin 10 mg daily for four weeks and Tab. diclofenac sodium 50 mg SOS for acute pain. The control group received Tab. diclofenac sodium 50 mg SOS for acute pain. We followed all patients for four weeks for expulsion of ureteric stones by X-ray KUB or CT KUB. Sex, age and stone size were matching variables. Stone expulsion (yes, no) was research variable. We compared count of stone expulsion between two groups by using McNemar chi-square test at alpha 0.5 using GraphPad.Results: Out of 30 patients in experimental group, 23 (76.67%) were men and seven (23.33%) women and out of 30 in control group, 20 (66.67%) were men and 10 (33.33%) women, almost similar in both groups. Mean age in experimental group was 39.45±10.33 years and in control group it was 37.38±8.28 years, almost similar in both groups. Mean stone size was 7.45±1.47 (5-10) mm in the experimental and 7.28±1.68 (5-10) mm in control group, being comparable in both the groups. In experimental group, stone expulsion was achieved in 23 (76.67%) cases and not in seven (23.33%) cases and in control group, it was achieved in 16 (53.33%) cases and not in 14 (46.67%) cases. There was statistically no significant difference in efficacy of alfuzosin versus control group (p=.1213).Conclusion: Our study showed no difference in efficacy of alfuzosin versus control group for upper ureteric stone expulsion in adult population of district Lahore, Pakistan.

Role of inflammatory markers and their trends in predicting the outcome of medical expulsive therapy for distal ureteric calculus

Objective:

Symptomatic ureteric stones cause surrounding inflammation-promoting obstruction. C-reactive protein (CRP), white blood cell count (WC), and neutrophil percentage (NP) tend to rise after inflammatory response. Monitoring response during the course of medical expulsive therapy (MET) may help in deciding early intervention, thereby decreasing morbidity. We assessed the role and trends of these markers in predicting the outcome of MET.

Materials and Methods:

One hundred and ninety-two patients with distal ureteric calculus of size >5 mm were included in this prospective study from April 2017 to March 2018 after ethical committee approval. CRP, NP, and WC were measured on day 1, 7, and 14 of MET, and analysis was done.

Results:

On univariate analysis, stone size and mean values of CRP, WC, and NP on day 1, 7 and 14 in stone nonpassers were significantly higher compared to stone passers (P < 0.05). Receiver operator curve analysis showed area under the curve value of 0.798 (P = 0.001) for CRP and cut off value determined was 1.35 mg/dL. Multivariate analysis of different variables showed significant association of higher CRP (>1.35 mg/dL) and larger stone size (>7 mm) with MET failure. Decreasing trend of CRP was seen in both groups, but values were higher in stone nonpassers. WC and NP showed decreasing trend in stone passers but persistently high in stone nonpassers.

Conclusions:

Higher CRP and larger stone size were associated with failure of MET. WC and NP showed decreasing trend in stone passers and persistently higher in nonpassers, which may potentially predict failure of MET, however, their role need to be further studied.

The Efficacy of Mirabegron in Medical Expulsive Therapy for Ureteral Stones: A Systematic Review and Meta-Analysis

BACKGROUND

This study aimed to assess the efficacy of mirabegron (50 mg daily) as a medical expulsive therapy for ureteral stones in adults.

MATERIALS AND METHODS

We searched PubMed, Embase, Cochrane Library, and Web of Science from inception to July 2021 to collect the clinical trials. Two reviewers independently screened literature, extracted data, and assessed the risk of bias of included studies by using the Cochrane risk of bias tool. Review Manager 5.3 software was used for the meta-analysis.

RESULTS

A total of four studies were included, involving 398 patients: 197 patients in mirabegron group and 201 patients in control group. The meta-analysis showed that the stone expulsion rate was higher in the mirabegron group than in the control group (OR: 2.12; 95% CI: 1.33 to 3.40; p=0.002). Subgroup analysis identified that the stone expulsion rate of patients with stone size <5/6 mm was significantly higher than that of patients with stone size ≥5/6 mm (OR: 0.31; 95% CI: 0.13 to 0.72; p=0.006). But no significant difference was identified between the mirabegron group and the control group for the stone expulsion interval (MD: -1.16, 95% CI: -3.56 to 1.24; p=0.35). In terms of pain episodes, the mirabegron group was significantly lower than that of the control group (MD: -0.34, 95% CI: -0.50 to 0.19; p < 0.0001).

CONCLUSIONS

The medical expulsive therapy with mirabegron had a significant effect in improving the stone expulsion rate for patients with ureteral stones, especially in those whose stone size <5/6 mm. Mirabegron had no effect on the stone expulsion interval but did decrease the pain episodes.

Treatment management of COVID-19 positive patients with renal colic secondary to distal ureteral stone

OBJECTIVE

In this study, we aimed to contribute to the literature by sharing and evaluating the clinical characteristics and our treatment and follow-up approaches in patients in the COVID-19 positive treatment process who had presented to our hospital's emergency department with a distal ureteral stone and to examine the effects of the pandemic and disease in this group of patients.

METHOD

The study included 14 patients infected with COVID-19 who had presented to the Erzurum City Hospital Emergency Department between August 2020 and December 2020 with the complaint of renal colic in which distal ureteral stones were detected in the tests. The demographic and clinical characteristics of patients, laboratory and radiological examinations, characteristics of ureteral stones, details of treatments applied to patients, treatment procedures of patients who had undergone surgical treatment, patient files, visit and operation notes and the patient discharge reports were retrospectively reviewed and evaluated.

RESULTS

The study included 14 patients. The average age of the patients was 35.7 (±14.35). The average stone size was 6.2 (±1.8) mm. Analgesic treatment and MET for distal ureteral stones were begun in 11 (78.6%) of the patients. Pain control was achieved in nine patients (64.2%) with analgesic treatment and MET, and the stone was removed without invasive intervention. Surgical intervention was performed in a total of five patients (35.7%).

CONCLUSION

In most COVID-19 infected patients with renal colic and a distal ureteral stone, results can be obtained using MET. Patients with a distal ureteral stone and persistent renal colic can be safely and effectively treated by endoscopic ureteral stone treatment after taking necessary precautions. Prospective, randomised, and controlled studies are required on this subject.

Impact of Multiparametric Stone Measurement in Noncontrast Computer Tomography on Ureterorenoscopic Stone Removal

PURPOSE

Low-dose computer tomography (NCCT) is the standard imaging modality for patients with acute flank pain with a suspicion of urolithiasis. The stone size is usually measured 2D by a radiologist. We compared 3D stone measurement using different windows to the 2D measurement and evaluated the clinical impact on ureterorenoscopic stone removal (URS).

METHODS

One hundred sixty-four patients (201 stones) with a preoperative NCCT, following a URS within 4 weeks, were included in this study. Stone location, number and size of stones, operating time, and laser lithotripsy were documented. Stones were measured in 3D using bone and soft tissue window. The maximum diameter was compared to the radiological report. The U test, Kruskal-Wallis, and regression were used for statistical analyses.

RESULTS

Almost two-thirds (64.68%; 130 stones) of stone measurements in 3D with the bone window were lower than the radiologist reports in 2D. One-third (34.83%; 70 stones) of stone measurements were higher and 0.5% (1 stone) reported the same size. Using the 3D soft tissue window, 81.09% (163 stones), 17.91% (37 stones), and 1% (2 stones) of stones were measured bigger, smaller, or had the same measurement results, respectively. In the clinical setting, we could calculate a cutoff for laser lithotripsy at a maximum stone diameter of 5.70 mm (p < 0.01) with the 3D and 6.01 mm with the 2D measurements, respectively, and found a significant correlation between maximum stone diameter and operating time (p < 0.01) and number of stones and operating time (p < 0.01 with and p = 0.02 without laser).

CONCLUSION

3D stone measurement with bone window seems to be more accurate than 2D measurement, but 2D is sufficient for planning stone treatment.

Comparison of efficacy of three commonly used alpha-blockers as medical expulsive therapy for distal ureter stones: A systematic review and network meta-analysis

Introduction:

The efficacy of alpha-blockers as medical expulsive therapy (MET) is well established. However, it is not known which of the three most commonly used alpha-blockers (tamsulosin, alfuzosin and silodosin) is the most efficacious. With this study we aimed to assess the efficacy of the three commonly used alpha-blockers as MET for distal ureter stones.

Materials and Methods:

For this review, we searched multiple databases such as PubMed/Medline, Scopus, Embase, OviD SP, CINAHL, and web of science to identify all the relevant randomized studies comparing the efficacy of tamsulosin, alfuzosin, and silodosin. Preferred reporting items for systematic reviews for network meta-analysis (PRISMA-NMA) were followed while conducting this review and the study protocol was registered with PROSPERO (CRD42020175706).

Results:

In this review, 31 studies with 7077 patients were included. Compared to placebo all the treatment groups were more effective for both stone expulsion rate (SER) and stone expulsion time (SET). For both SER and SET, silodosin had the highest SUCRA (94.8 and 90.4) values followed by alfuzosin (58.8 and 64.9) and tamsulosin (46.2 and 44.5). The incidence of postural hypotension was similar with all the drugs, whereas, the incidence of retrograde ejaculation was significantly higher for silodosin. Overall confidence for each comparison group in this review ranged from “very low” to “moderate” according to the CINeMA approach.

Conclusion:

Among the three commonly used alpha-blockers silodosin is the most efficacious drug as MET for lower ureter stones followed by alfuzosin and tamsulosin.

Spontaneous ureteral stone passage: a novel and comprehensive nomogram

BACKGROUND

Ureteral stones pose a high economic and medical burden among Emergency Department (ED) admissions. Management strategies vary from expectant therapy to surgical interventions. Since predictors of ureteral spontaneous stone passage (SSP) are still not well understood, we sought to create a novel nomogram to guide management decisions.

METHODS

Charts were retrospectively reviewed for patients who presented to our institution's ED with non-febrile renal colic and received a radiological diagnosis of ureteral stone ≤10 mm. Demographic, clinical, laboratory, and non-contrast CT data were collected. This novel nomogram incorporates the serum neutrophil-to-lymphocyte ratio (NLR) as a potential predictor of SSP. The model was derived from a multivariate logistic regression and was validated on a different cohort. A receiver operator characteristic (ROC) curve was constructed and the area under the curve (AUC) was computed.

RESULTS

A total of 1186 patients presented to our ED between January 2010 and October 2018. We randomly divided our population into a derivation and validation cohort in one to five ratio. A stone size ≥7 mm was the strongest predictor of SSP failure; OR=9.47; 95% CI: 6.03-14.88. Similarly, a NLR≥3.14 had 2.17; (1.58-2.98) the odds of retained stone. SSP failure was also correlated with proximal position, severe hydronephrosis, and leukocyte esterase ≥75, P=0.02, P=0.05, and P=0.006, respectively. The model had an AUC of 0.804 (0.776-0.832). The nomogram was also used to compute the risk of SSP failure (AUC 0.769 [0.709-0.829]).

CONCLUSIONS

Our novel nomogram can be used as a predictor for SSP and can be used clinically in decision making.

Association between time to lithotripsy and stone-free rate in patients with ureteral stones undergoing shock wave lithotripsy

Early shock wave lithotripsy is associated with higher stone-free rate compared to delayed treatment of ureteral stones, but may constitute overtreatment because ureteral stones can pass spontaneously. We studied the association between time to treatment and stone-free rate in patients with ureteral stones to determine optimal shock wave lithotripsy timing. We retrospectively analyzed 537 patients undergoing shock wave lithotripsy for ureteral stones. Patients were divided into five groups according to time from onset of symptoms to lithotripsy—urgent (0–3 days), early (4–30 days), late (31–60 days), long-delayed lithotripsy (≥ 61 days), and asymptomatic. Stone-free rates were compared among groups. Mean age and stone size were 55.6 ± 13.1 years and 7.48 ± 3.29 mm, respectively. Mean number of shock wave lithotripsy sessions and stone-free rate were 1.37 and 91.6%, respectively, in the overall population. Stone-free rates were 95.2%, 96.8%, 91.3%, 86.3%, and 82.7% in urgent, early, late, long-delayed lithotripsy, and asymptomatic groups, respectively. Long-delayed lithotripsy and asymptomatic groups had significantly more lithotripsy sessions and lower stone-free rate, compared to urgent and early lithotripsy groups. In multivariate analysis, time to lithotripsy [long-delayed lithotripsy (odds ratio: 0.273, p = 0.004) and asymptomatic nature (odds ratio: 0.236, p = 0.002)] and age (odds ratio: 0.959, p = 0.003) independently affected stone-free rate. In conclusion, time to lithotripsy is a strong predictive factor for stone-free status following shock wave lithotripsy. Urgent shock wave lithotripsy did not improve stone-free rate if performed within 1 month. However, time to shock wave lithotripsy > 2 months reduced likelihood of stone-free status.

Clinical and Radiological Predictors of Early Intervention in Acute Ureteral Colic

PURPOSE

Acute ureteric colic (AUC) is generally one of the most common reasons for emergency department attendance. Expectant management is recommended in non-complicated ureteral calculi. However, data regarding the optimal duration of observation or indications of early intervention (EI) are not well understood. This article describes the clinical and radiological factors that promote EI in AUC.

PATIENTS AND METHODS

This was an observational and retrospective cohort study. Patients with AUC diagnosed based on non-contrast computerized tomography (NCCT) between 2019 and 2020 were enrolled in the study. These patients were classified into two main categories: spontaneous passage of stone (SSP) and EI. In addition, a comparative analysis was performed to identify clinical and radiological variables that promote EI.

RESULTS

One-hundred and sixty-one patients were included. High WBCs are associated with a significant increase in EI. Forty-three percent (n=37) of patients with serum WBCs higher than 10 had an EI, while 23% had SSP (n=17;p<0.001). High CRP level is also significantly associated with EI (n=36; 86%; p<0.001). Upper and middle ureteral calculi are statistically associated with EI (n=54; 62%) in comparison to the SSP cohort (n=22; 30%;p<0.001). EI is also linked to the maximal length of ureteric calculi (MCL) of 9 mm (6-13mm), and HU density of stone of 700 (430-990) H.U (p<0.001). Ureteric stone volume of 0.2 (0.06-0.3) cm³ is significantly associated with EI (p<0.001). Ureteral wall thickness of 3 (2-3 mm), the presence of extrarenal pelvis (n=20; 23%), and AP diameter of renal pelvis 18 (13-28 mm) are all significantly associated with a higher rate of EI (p<0.001). Multiple binary logistic regression analysis showed that MCL is the strongest predictor of EI.

CONCLUSION

MCL is an independent and robust predictor of EI in AUC. Biochemical variables and radiological characteristics can also act as an adjunct to promote EI.

Non-surgical treatment of urinary stone

Some patients with urinary stones can be managed non-surgically through observation, medication, or extracorporeal shockwave lithotripsy (ESWL). Symptomatic urinary stones can initially be treated conservatively using analgesics and hydration. When uncontrolled pain or infection is present, immediate diversion via either percutaneous nephrostomy or ureteral stenting may be necessary. Medical expulsive therapy utilizing alpha-blocker may benefit a selected group of patients with stones larger than 5 mm. Oral or percutaneous chemolysis is a well-established non-invasive option with a reasonable success rate for patients with a certain component such as uric acid. When medical treatment is applied, its unintended side effects should be considered and routinely monitored. Extracorporeal shockwave lithotripsy is a highly effective and safe modality in treating urinary stones when adequately indicated. In addition to the size and location of the stone, information obtained from non-enhanced computed tomography such as stone density, stone heterogenicity index, and stone-to-skin distance can be applied to predict the possibility of ESWL failure. Modifications in shock wave delivery by altering shock rate and voltage can improve shock wave efficacy. Urinary stones can be managed effectively and safely using non-surgical approaches.

Urolithiasis in the COVID Era: An Opportunity to Reassess Management Strategies

Delayed evaluation and/or treatment for urolithiasis during the COVID-19 pandemic provide a unique opportunity to organically reassess many well-established stone management strategies. Nonopioid analgesia for renal colic and spontaneous passage trials appear to be two avenues worthy of investigation.

Prediction of stone-free rates following extracorporeal shockwave lithotripsy in a contemporary cohort of patients with stone densities exceeding 1000 HU

Purpose: Nephrolithiasis is a common urologic problem, and its incidence is increasing. Shockwave Lithotripsy (SWL) has better results for patients with stones < 1000 HU. We attempted to identify SWL stone-free (SF) predictors for > 1000 HU stones.Methods: From January 2013 to September 2019, patient shared decision consecutive SWL for the treatment of a single > 1000 HU renal stone diagnosed by non-contrast computed tomography (NCCT). Endpoints: Fragmentation and SF or clinically insignificant residual fragments ≤ 4 mm at 4 weeks. Age, gender, stone side, location, size and density, number and average energy (Joules) of shocks were explored on uni- and multivariate regression analysis.Results: All sixty-one patients included were diagnosed with renal stone between 5 and 20 mm (maximum length) and underwent one SWL session only: 62.3% males, median age 48 (21-80) years, mean stone size 9.43 ± 2.9 mm (6.0-20.0), mean density 1210 ± 135 HU (1000-1558). There were 39 (63.9%) cases of SF, 16 (26.2%) of partial success and six (9.8%) of no success. Stone size was the only independent predictor of fragmentation, OR = 1.83, 95% CI = 1.32-2.55, p = 0.0003, and SF OR = 1.91, 95% CI = 1.31-2.78, p = 0.008. The best discriminatory stone size on ROC analysis was 1 cm.Conclusion: Stone size was the only significant success predictor in our cohort, with 76% SF rate for stones < 1 cm in 4 weeks follow-up, supporting that renal stones > 1000 HU may be suitable to SWL.

Urethral Calculi

Urolithiasis is a condition with calculi commonly found within the kidney, ureter, or bladder. The urethra is an uncommon location of urolithiasis, with limited case reports and literature reviews of its presentation and management. Here we discuss a 24-year-old female who presented with urinary urgency, flank pain, and urinary retention for 12 hours. Physical exam showed a calculus at the urethral meatus. This case discusses the manual removal of a urethral calculus in a female patient with use of forceps, resulting in complete resolution of symptoms and urinary retention.

Analysis of stones formed in the human gall bladder and kidney using advanced spectroscopic techniques

Stone diseases (gallstones and kidney stones) are extremely painful and often cause death. The prime aim of biomedical research in this area has been determination of factors resulting in stone formation inside the gallbladder and urinary tract. Many theories have been put forward to explain the mechanism of stone formation and their growth; however, their complete cycle of pathogenesis is still under debate. Several factors are responsible for stone formation; however, much emphasis is placed on the determination of elemental and molecular composition of the stones. In the present review article, we describe different kinds of spectroscopic techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray fluorescence (XRF) spectroscopy, time-of-flight secondary ion mass spectrometry (TOF-SIMS), and laser-induced breakdown spectroscopy (LIBS) and highlight their use in the analysis of stone diseases. We have summarized work done on gallstones and kidney stones using these advanced techniques particularly over the last 10 years. We have also briefly elaborated the basics of stone formations inside the human body and their complications for a better understanding of the subject.

Urinary Stone Disease in Pregnancy: Current Management Practices in a Large National Cohort

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.

An investigation of elastic waves producing stone fracture in burst wave lithotripsy

Burst wave lithotripsy is a method to noninvasively fragment urinary stones by short pulses of focused ultrasound. In this study, physical mechanisms of stone fracture during burst wave lithotripsy were investigated. Photoelasticity imaging was used to visualize elastic wave propagation in model stones and compare results to numerical calculations. Epoxy and glass stone models were made into rectangular, cylindrical, or irregular geometries and exposed in a degassed water bath to focused ultrasound bursts at different frequencies. A high-speed camera was used to record images of the stone during exposure through a circular polariscope backlit by a monochromatic flash source. Imaging showed the development of periodic stresses in the stone body with a pattern dependent on frequency. These patterns were identified as guided wave modes in cylinders and plates, which formed standing waves upon reflection from the distal surfaces of the stone model, producing specific locations of stress concentration in the models. Measured phase velocities compared favorably to numerically calculated modes dependent on frequency and material. Artificial stones exposed to bursts produced cracks at positions anticipated by this mechanism. These results support guided wave generation and reflection as a mechanism of stone fracture in burst wave lithotripsy.

Hounsfield unit and its correlation with spontaneous expulsion of lower ureteric stone

Background:

Hounsfield unit (HU) is the measure of stone density, and is utilized in the predetermination of type of stone. The purpose of this study was to identify some factors in noncontrast computed tomography (NCCT) of kidney, ureter, and bladder (KUB) that are easily extractable and can be used to determine the outcome of expectant management.

Methods:

All patients 18–50 years of age who presented with flank pain and diagnosed as having lower ureteric calculi of size 5–10 mm by NCCT KUB were included in the study. HU of stone was calculated from the mean HU at three different regions of interest. We prescribed tamsulosin for 4 weeks as medical expulsive therapy. We divided the patients into two groups: group A included patients with successful expulsion of stone, and group B included patients who failed to pass stone. We compared age, gender, laterality, stone size in axial and coronal section of NCCT, HU of stone, blood urea, creatinine, and renal parenchymal thickness.

Results:

A total of 180 patients with lower ureteric calculus were included in the study. The mean age of patients was 34 years, with male:female ratio of 2.3:1. Of these 180 patients, 119 (66%) successfully expelled the stone and were included in group A, with the remaining 61 (34%) forming group B. In univariate analysis, longitudinal diameter of stone (p < 0.001), transverse diameter of stone (p < 0.001) and high HU (p < 0.001) were significantly associated with failure of expulsion. However, in multivariate analysis only longitudinal diameter of stone (p < 0.001) differed significantly among groups. Differences in HU (p = 0.179) and transverse diameter of stone (p = 0.108) did not reach significance level.

Conclusions:

Lower ureteric calculi are definitely amenable to conservative management. Longitudinal diameter of stone can be a useful parameter; however, HU and its derivatives cannot be used as a predictor of outcome.

Can negative ureteroscopy be predicted in ureteral stone treatment?

INTRODUCTION

We aimed to evaluate factors predictive of negative ureteroscopy (URS) in ureteral stones.

METHODS

Patients who underwent URS between January 2007 and June 2018 were included in the study. Patients were divided into two groups: group 1- positive URS (841 patients); and group 2 -negative URS (75 patients). These two groups were compared in terms of demographic data, stone characteristics, and postoperative outcomes.

RESULTS

The mean age of the study patients was 44.5±15.1 years. The absence of collecting system dilatation due to the present stone was found to be a significant predictive factor for negative URS in univariate analysis, but there was no significant difference in multivariate analysis. In the multivariate analysis, low body mass index (BMI), no history of stone surgery, stone located in the distal ureter, small stone area, longer time between the last imaging procedure and URS, and medical expulsive therapy (MET) application were statistically significant in predicting negative URS.

CONCLUSIONS

In this study, the parameters that significantly predicted negative URS were found to be low BMI, no history of stone surgery, distal localization of the stone, small stone area, longer time between the last imaging procedure and URS, and MET applied for the current stone. These parameters should be considered to avoid negative URS and patients should be informed of the possibility of negative URS prior to operation.

Computed tomography window affects kidney stones measurements

OBJECTIVES

Measurements of stone features may vary according to the non-contrast computed tomography (NCCT) technique. Using magnified bone window is the most accurate method to measure urinary stones. Possible differences between stone measurements in different NCCT windows have not been evaluated in stones located in the kidney. The aim of this study is to compare measurements of kidney stone features between NCCT bone and soft tissue windows in patients submitted to retrograde intrarenal surgery (RIRS).

MATERIALS AND METHODS

Preoperative and 90th postoperative day NCCT were performed in 92 consecutive symptomatic adult patients (115 renal units) with kidney stones between 5 mm to 20 mm (< 15 mm in the lower calyx) treated by RIRS. NCCT were evaluated in the magnified bone window and soft tissue window in three axes in a different time by a single radiologist blinded for the measurements of the NCCT other method.

RESULTS

Stone largest size (7.92±3.81 vs. 9.13±4.08; mm), volume (435.5±472.7 vs. 683.1±665.0; mm3) and density (989.4±330.2 vs. 893.0±324.6; HU) differed between bone and soft-tissue windows, respectively (p<0.0001) 5.2% of the renal units (6/115) were reclassified from residual fragments > 2 mm on soft tissue window to 0-2 mm on bone window.

CONCLUSION

Kidney stone measurements vary according to NCCT window. Measurements in soft tissue window NCCT of stone diameter and volume are larger and stone density is lesser than in bone window. These differences may have impact on clinical decisions.

Impact of the Image Gently® Campaign on Computerized Tomography Use for Evaluation of Pediatric Nephrolithiasis

PURPOSE

The Image Gently® campaign was launched by several radiological societies in 2007 to promote safe imaging in children. A goal of the campaign was to reduce ionizing radiation exposure in children. Given the recurrent nature of kidney stones, affected children are at risk for unnecessary ionizing radiation exposure from computerized tomography. We sought to determine whether the Image Gently campaign led to a decrease in the use of computerized tomography for evaluating children with nephrolithiasis. We hypothesized that the campaign was the primary cause of a reduction in the use of computerized tomography.

MATERIALS AND METHODS

We analyzed medical claims data from 2001 to 2015 identifying children with nephrolithiasis covered by the same commercial insurance provider. Using a difference in differences design, we estimated changes in computerized tomography use after the campaign started among patients less than 18 years old compared to a control group age 18 years or older with nephrolithiasis.

RESULTS

We identified 12,734 children and 787,720 adults diagnosed with nephrolithiasis. Before 2007 quarterly rates of computerized tomography use during a stone episode (per 1,000 patients) were increasing at a parallel rate in children and adults (5.1 in children vs 7.2 in adults, p = 0.123). After the Image Gently campaign started the use of computerized tomography decreased in both groups but at a slightly higher rate in adults (difference in differences 2.96, 95% CI 0.00 to 5.91, p = 0.050).

CONCLUSIONS

Although there has been a reduction in the use of computerized tomography among children with nephrolithiasis, given a similar trend seen in adults this change cannot be primarily attributed to the Image Gently campaign.

Factors associated with spontaneous stone passage in a contemporary cohort of patients presenting with acute ureteric colic: results from the Multi-centre cohort study evaluating the role of Inflammatory Markers In patients presenting with acute ureteric Colic (MIMIC) study

OBJECTIVES

To assess the relationship of white blood cell count (WBC) and other routinely collected inflammatory and clinical markers including stone size, stone position, and medical expulsive therapy use (MET), with spontaneous stone passage (SSP) in a large contemporary cohort of patients with acute ureteric colic, as there are conflicting data on the role of WBC and other inflammatory markers in SSP in patients with acute ureteric colic.

PATIENTS AND METHODS

Multicentre retrospective cohort study coordinated by the British Urology Researchers in Surgical Training (BURST) Research Collaborative at 71 secondary care hospitals across four countries (UK, Republic of Ireland, Australia, and New Zealand). In all, 4170 patients presented with acute ureteric colic and a computed tomography confirmed single ureteric stone. Our primary outcome measure was SSP, as defined by the absence of need for intervention to assist stone passage (SP). Multivariable mixed effects logistic regression was used to explore the relationship between key patient factors and SSP.

RESULTS

In all, 2518 patients were discharged with conservative management and had further follow-up with a SSP rate of 74% (n = 1874/2518). Sepsis after discharge with conservative management was reported in 0.6% (n = 16/2518). On multivariable analysis neither WBC, neutrophils count, nor C-reactive protein (CRP) predicted SSP, with an adjusted odds ratio (OR) of 0.97 (95% confidence interval [CI] 0.91-1.04, P = 0.38), 1.06 (95% CI 0.99-1.13, P = 0.1) and 1.00 (95% CI 0.99-1.00, P = 0.17), respectively. MET also did not predict SSP (adjusted OR 1.11, 95% CI 0.76-1.61). However, stone size and stone position were significant predictors. SSP for stones <5 mm was 89% (95% CI 87-90) compared to 49% (95% CI 44-53) for stones ≥5-7 mm, and 29% (95% CI 23-36) for stones >7 mm. For stones in the upper ureter the SSP rate was 52% (95% CI 48-56), middle ureter was 70% (95% CI 64-76), and lower ureter was 83% (95% CI 81-85).

CONCLUSION

In contrast to the previously published literature, we found that in patients with acute ureteric colic who are discharged with initial conservative management neither WBC, neutrophil count, nor CRP, helps determine the likelihood of SSP. We also found no overall benefit from the use of MET. Stone size and position are important predictors and our present findings represent the most comprehensive SP rates for each millimetre increase in stone size from a large contemporary cohort adjusting for key potential confounders. We anticipate that these data will aid clinicians managing patients with acute ureteric colic and help guide management decisions and the need for intervention.

Association of spontaneous expulsion with C-reactive protein and other clinico-demographic factors in patients with lower ureteric stone

The purpose of our study is to analyze the definitive relation of C-reactive protein (CRP) and other factors with the spontaneous stone passage in patients with distal ureteric calculus of 5-10 mm and to calculate the risk of failure of expectant management in patients. 185 patients of ureteric colic, who were subjected to medical expulsive therapy (MET), were included prospectively from August 2016 to May 2018 and followed up for 4 weeks. Patients were divided into two groups. Group A included successful spontaneous passage patients and group B included failure in the same. The parameters analyzed were age, gender, longitudinal and transverse diameter of stone, CRP, total leucocyte count, ureteric diameter and hydroureteronephrosis (HUN). We performed univariate and multivariate analysis. Receiver operating characteristics curve was used to determine the cutoff value for significantly associated variables. 122 (65.90%) and 63 (34.10%) patients were included in group A and B, respectively. In univariate analysis, CRP, longitudinal and transverse diameter of stone, HUN, proximal and distal ureteric diameters were statistically significant. However, in multivariate analysis, only negative CRP (p = 0.002), smaller longitudinal diameter of stone (p < 0.001) and absence of HUN (p = 0.005) were significantly associated with successful expulsion. Cutoff for CRP was 0.41 mg/dl and longitudinal diameter was 6.7 mm. The success rate in the group of patients with no risk factor was 96.7% and with all three risk factors was 16.7%. Patients with a longitudinal diameter of stone > 6.7 mm, HUN, and CRP > 0.41 mg/dl should be considered for early intervention. The success rate of MET can be increased to 86% after exclusion of patients with all three risk factors.

Pediatric Urinary Stone Disease in the United States: The Urologic Diseases in America Project

OBJECTIVE

To examine the recent epidemiology of pediatric urinary stone disease (USD) in the United States.

METHODS

We utilized the 2004-2016 Optum^© Clinformatics® Data Mart database, a de-identified adjudicated administrative health claims database that includes 15-18 million individuals covered annually by commercial insurance in all 50 US states. The analysis included 12,739,125 children aged 0-18 years. We calculated annual rates of USD, ambulatory visits, and procedures, and the prevalence of prescription fills.

RESULTS

The 2005-2016 USD rate was 59.5 cases per 100,000 person-years. The annual rate rose gradually from 2005 to a peak of 65.2 cases per 100,000 person-years in 2011. The USD rate increased with increasing age, and was highest among females compared to males, non-Hispanic Whites compared to other race/ethnic groups, and those residing in the South compared to other geographic regions. The overall 2005-2016 rate in the 120 days following a USD episode was 1.9 for ambulatory visits, 0.24 for surgical procedures, and 1.1 for imaging procedures. Ureteroscopy was the most common surgical procedure and CT scan was the most common imaging procedures, although ultrasound utilization increased over time. Medications were filled in 46.9% of cases, and use was lowest among males (43.1%), Asians (34.8%), and in the Northeast (34.3%). Opiate agonists were the most prevalent prescription (39.9%).

CONCLUSION

Our study provides one of the most comprehensive examinations of pediatric USD to date, demonstrating shifting rates and treatment patterns over time, as well as differences by age, gender, race/ethnicity, and geographic region.

Efficacy and safety of phosphodiesterase type 5 inhibitors for the treatment of distal ureteral calculi of 5 to 10 mm in size: A systematic review and network meta-analysis

To evaluate the Efficacy and safety of phosphodiesterase type 5 inhibitors as a medical therapy for distal ureteral calculi by means of a systematic review and network meta-analysis (NMA). We searched the Embase, Medline, and the Cochrane Central Register of Controlled Trials for randomised controlled trials (RCTs) published before May, 2017. Stone passage rate as the primary outcome. We used random effects model for pairwise meta-analyses and Bayesian random effects model for NMA. We evaluated the quality of evidence by the GRADE framework for each network estimate. Five RCTs (861 patients) comparing four different interventions. The results of NMA showed that compared with tamsulosin alone, tamsulosin combined with tadalafil group was associated with significantly higher stone passage rate (odds radio [OR] 2.55, 95% credible intervals [Crl] 1.11 to 5.89). When considering stone expulsion rate, compared with tamsulosin, silodosin was ranked best (OR 3.58, 95% Crl 1.13 to 11.91), followed by tamsulosin combined with tadalafil (OR 2.55, 95% Crl 1.11 to 5.89) and tadalafil alone (OR 1.86, 95% Crl 0.95 to 4.25). No significant difference was found considering safety profiles between any interventions. This meta-analysis indicates that tamsulosin combined with tadalafil is an effective treatment option for ureteral stones with a low occurrence of side effects. Clinicians should take all known safety and compliance of patients into account when choosing an optimal strategy. Since sample size of included studies, further RCTs are strongly encouraged to address the clinical question.