Spontaneous Stone Passage Rates of Ureteric Stones After Stenting for Acute Renal Colic: A Systematic Review

MP22-07 SPONTANEOUS PASSAGE OF URETERAL STONES FOLLOWING STENT PLACEMENT

Ureteral calculi can be associated with urinary drainage blockage, requiring urinary diversion with percutaneous nephrostomy (PCN) or retrograde ureteral stent (RUS). Currently no evidence exists to support the superiority of one method over the other. This study proposes to compare both approaches regarding the probability of spontaneous stone passage (SSP) and its effect on patient's quality of life (QoL). A prospective trial was carried out from July to October of 2017. 50 patients were selected with hydronephrosis secondary to ureteral stones requiring urgent urinary diversion and divided into two groups according to diversion technique: percutaneous nephrostomy (PCN) or retrograde ureteral stent (RUS). The rate of SSP and QoL were evaluated. A PCN group (18 patients) and a RUS group (32 patients) were set. Stone size was higher in PCN (median 92mm2) than RUS (median 47mm2) (p = .012). The rate of SSP was 25% in RUS group and 38.9% in PCN. On the univariable analysis no statistical effect was found; however, when adjusted for stone size, location, previous ureteral manipulation and expulsive therapy, PCN showed a significant higher chance of SSP than RUS (OR = 6667). Besides, it was found that 30.2% (n = 13) of stones had an upward displacement associated with retrograde endoscopy. A significant decrease between pre- and post-intervention QoL was found with RUS (p < .001), but not found with PCN (p = .206). Patients in RUS group experienced more urinary symptoms, mostly haematuria (68.7% vs 16.7% in PCN group < .001) and dysuria (78.3% vs 16.7% in PCN group, p < .001). PCN was associated with a higher rate of spontaneous stone passage when adjusted for stone size and location. Moreover, PCN was better tolerated and associated with fewer urinary symptoms when compared with RUS.

MP15-05 PERCUTANEOUS NEPHROSTOMY, URETERAL STENT OR PRIMARY URETEROSCOPY WITH STONE REMOVAL FOR THE TREATMENT OF HYDRONEPHROSIS SECONDARY TO URETERIC CALCULI: A PROSPECTIVE EVALUATION OF THE IMPACT ON COMPLICATIONS, STONE MANAGEMENT AND HEALTH-RELATED QUALITY OF LIFE

BackgroundAnimal studies have shown that nicotine affects the peristalsis of the ureter. The aim of the study is to analyze the effect of smoking on spontaneous passage of distal ureteral stones.Methods88 patients in whom distal ureteral stone below 10 mm diameter diagnosed with helical computerized tomography enhanced images were reviewed. Patients were grouped as either smokers (n:33) or non smokers (n:50). Follow-up for spontaneous passage of stones was limited with 4 weeks. Patients did not receive any additional medical treatment other than non-steroid anti inflamatory drugs only during painful renal colic episodes.Two groups were compared with the chi-square test in terms of passing the stone or not. Stone passage was confirmed with either the patient collecting the stone during urination or by helical CT.ResultsSmoking habits was present in 30(34%) patients and the frequency in both groups were similar (smokers: 23(76%) vs non-smokers: 46(79%)). Spontaneous passage of the stone was observed in 69(78%) patients. The two groups were comparable in terms of patien age, male to female ratio and stone size. Stone passage decreased as stone diameter increased. Total stone passage rates were similar in both groups (smokers: 76% vs. non-smokers: 79%) (p > 0.05). Passage of stones > 4 mm was observed in 46% and 67% of smokers and non-smokers respectively. However passage of stones with a diameter ≤ 4 mm were similar in both groups (smokers: 100% vs non-smokers: 92%) (p > 0.05).ConclusionSmoking has neither a favorable nor un-favorable effect on spontaneous passage of distal ureteral stones. However, spontaneous passage rates in patients with a stone diameter > 4 mm was lower in smokers. These results should be further confirmed with studies including larger numbers of patients.

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

MP26-19 TAMSULOSIN INCREASES SPONTANEOUS PASSAGE OF URETERAL STONES IN CHILDREN

Standardization of the management of pediatric urolithiasis in the emergency department

Alfuzosin Stone Expulsion Therapy for Distal Ureteral Calculi: A Double-Blind, Placebo Controlled Study

The management of acute renal colic is a problem commonly encountered by both urologists and emergency medicine physicians. The classic approach to managing uncomplicated acute renal colic involves hydration, along with imaging and pain control. Previous studies have suggested that hydration has a significant impact on patient comfort, as well as spontaneous stone passage. This study evaluated the effects of maintenance v forced hydration and its effect on the pain experienced from renal colic. Forty male and 18 female patients with a mean age of 41 years suspected to have acute renal colic were identified in the emergency department. After screening and informed consent, the patients were enrolled in the study, and 43 patients were eventually available for analysis. Patients received intravenous (IV) analgesia, imaging with a noncontrast CT scan of abdomen and pelvis, and assignment to either forced IV hydration with 2 L of normal saline over 2 hours (N = 20) or minimal IV hydration at 20 mL of normal saline per hour (N = 23). A visual analog pain scale was completed hourly for a total of 4 hours. Demographic information, laboratory and imaging results, narcotic use in morphine equivalents (ME), and pain scores were recorded and compared. Spontaneous stone passage rates were also calculated by careful patient follow-up. Results were considered statistically significant at p < 0.05. Stone size was equivalent in the two treatment groups (p > 0.05). There was no difference in the narcotic requirement in ME (p = 0.644) between the two groups. Similarly, there was no difference in hourly pain score or stone-passage rates between the groups (p > 0.05). Treatment of uncomplicated renal colic has traditionally included vigorous intravenous hydration, as well as medications for the control of pain and nausea. Our data suggest that maintenance intravenous fluids are as efficacious as forced hydration with regard to patient pain perception and narcotic use. Moreover, it appears the state of hydration has little impact on stone passage.

ObjectivesTo determine how to most accurately predict the chance of spontaneous passage of a ureteral stone using information in the diagnostic non-enhanced computed tomography (NECT) and to create predictive models with smaller stone size intervals than previously possible.MethodsRetrospectively 392 consecutive patients with ureteric stone on NECT were included. Three radiologists independently measured the stone size. Stone location, side, hydronephrosis, CRP, medical expulsion therapy (MET) and all follow-up radiology until stone expulsion or 26 weeks were recorded. Logistic regressions were performed with spontaneous stone passage in 4 weeks and 20 weeks as the dependent variable.ResultsThe spontaneous passage rate in 20 weeks was 312 out of 392 stones, 98% in 0–2 mm, 98% in 3 mm, 81% in 4 mm, 65% in 5 mm, 33% in 6 mm and 9% in ≥6.5 mm wide stones.The stone size and location predicted spontaneous ureteric stone passage. The side and the grade of hydronephrosis only predicted stone passage in specific subgroups.ConclusionSpontaneous passage of a ureteral stone can be predicted with high accuracy with the information available in the NECT. We present a prediction method based on stone size and location.Key Points• Non-enhanced computed tomography can predict the outcome of ureteral stones.• Stone size and location are the most important predictors of spontaneous passage.• Prediction models based on stone width or length and stone location are introduced.• The observed passage rates for stone size in mm-intervals are reported.• Clinicians can make better decisions about treatment.

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. 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. 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 <5mm was 89% (95% CI 87-90) compared to 49% (95% CI 44-53) for stones ≥5-7mm, and 29% (95% CI 23-36) for stones >7mm. 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). 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.

Background: Ureteral stones are common problems in daily emergency department practice. Ureteric stone is responsible for 20%. Ureter obstruction caused by a ureteral stone triggers inflammatory changes in the proximal submucosal layer and prevents passage of the stone. C reactive protein (CRP) was found to be an indicator of ureteral stone outcome. The objective of this study was to measure serum CRP for patients with 4-8 mm distal ureteric stone and use its level as predictive factor for spontaneous stone passage.Methods: A prospective study was designed on a total of 73 patients (M=34; F=39) who were in the age group (18-50) years, who presented with ureteral colic secondary to a solitary unilateral, 4 to 8 mm distal ureteral stone. Patients were grouped according to spontaneous stone passage. The patients were selected at the urology unit, in Ghazi AL Hariri Hospital for Specialized Surgery, Medical City Complex in Baghdad from October 2014 till October 2016. The follow up continued until the stone spontaneously passed, as reported by the patient, or for a maximum period of 4 weeks.Results: Age, BMI, and gender did not show significant difference between the two groups ;30 have spontaneous stone passage (SSP), and 43 no spontaneous stone passage (no SSP). Stone size is significantly higher in the group without SSP their median is 6 mm compared to 4 mm for SSP group. CRP is significantly elevated in no SSP group compared to SSP. CRP, stone size and previous history of stone passage was the only significant and independent predictors of SSP (low CRP, low stone size, and positive history predict SSP). Conclusions: Stone size, CRP, previous Hx of stone passage are independent predictors for SSP. Measuring serum CRP levels is useful for predicting whether spontaneous ureteral stone passage will be successful. More aggressive treatment methods such as URS should be considered when serum CRP levels is high.

In ureterolithiasis, the prediction of spontaneous passage poses a challenge for urologists. Moreover, there is controversy surrounding the preferred management approach, whether medical or surgical, as each approach has its disadvantages. Procalcitonin and other inflammatory markers were studied for predicting stone passage spontaneously, but their significance remains controversial. This study aims to assess the association between these markers, especially procalcitonin, and spontaneous ureteral stone passage. In this multicenter prospective cohort study from March 2022 to October 2023, consecutive patients with a single unilateral distal ureteric stone less than 10 mm were enrolled. Exclusion criteria were specified. Patients underwent medical expulsive therapy (MET) and were monitored for stone passage. The significance level was set at p < 0.05. Out of 94 patients enrolled, 72.3% were male and 27.7% were female, with a mean age of 38.84± 10.41 years. Stone sizes varied, with the most common range being 4 mm- 5.9 mm. Participants were categorized based on spontaneous stone passage as spontaneous stone passage (SSP) and non-SSP. No significant differences were observed in most demographic and laboratory variables. However, serum procalcitonin and C-reactive protein showed significant differences between the SSP and non-SSP groups. Although several inflammatory markers were studied to predict the spontaneous passage of the ureteral stone, the current study concluded that only elevated procalcitonin, C-reactive protein, and large stone diameter decrease the chance of spontaneous ureteral stone passage.

MP18-02 EVALUATING SPONTANEOUS STONE PASSAGE RATES DURING THE COVID-19 PANDEMIC

Little is known about the spontaneous passage of bile duct stones. The aim of this study was to determine the rate of spontaneous stone passage and relate it to the clinical presentation of the bile duct stone. Prospectively collected data were studied on a total of 1000 consecutive patients undergoing laparoscopic cholecystectomy with or without laparoscopic common duct exploration. Comparisons were made between 142 patients with common bile duct stones (CBDS), 468 patients who had no previous or current evidence of duct stones, and 390 patients who had good evidence of previous duct stones but none at the time of cholecystectomy. The evidence used for previous duct stones included a good history of jaundice or pancreatitis. In patients with biliary colic or cholecystitis, abnormal pre-operative liver function tests and/or a dilated common bile duct were taken as evidence of bile duct stones. Of the 1000 patients studied, 532 had evidence of stones in the common bile duct at some time prior to cholecystectomy. At the time of operation, only 142 patients had bile duct stones. By implication, 80%, 84%, 93% and 55% of patients presenting with pancreatitis, colic, cholecystitis and jaundice (73% overall) had passed their bile duct stones spontaneously. All 4 patients with cholangitis had duct stones at the time of operation. It is likely that most bile duct stones (3 in 4) pass spontaneously, especially after pancreatitis, biliary colic and cholecystitis but less commonly after jaundice. Cholangitis appears to be always associated with the presence of duct stones at the time of operation.