Patients' poor performance status is an independent risk factor for urosepsis induced by kidney and ureteral stones.

This study was aimed to identify the risk factors for urosepsis caused by kidney and ureteral stones. One hundred and nine patients who had kidney or ureteral stones and who were treated with trans-ureteral lithotripsy (TUL) at our institution from 2016 to 2020 were included. We investigated the risk factors for urosepsis caused by kidney or ureteral stones that occurred prior to TUL. Thirty patients (28%) had urosepsis prior to TUL. Patients were divided into a urosepsis group (n = 30, 28%) and a non-urosepsis group (n = 79, 72%). Patients' characteristics (gender, age, performance status [PS] score, presence of diabetes mellitus, and skeletal muscle mass), as well as their stone and urine characteristics (stone size, presence of obstructive ureteral stones, stone composition, and urine and stone cultures), were compared between the two groups. When compared to the non-urosepsis group, patients with urosepsis were more likely to be older (p < 0.001), female (p < 0.001), with lower skeletal muscle mass (p < 0.001) and with poor PSs (p < 0.001). For stone and urine characteristics, infection stones (p = 0.01), positive urine (p < 0.001) and stone culture (p = 0.007) were more often detected in patients with urosepsis. A multivariate analysis showed patients' poor PS to be an independent risk factor for urosepsis due to kidney and ureteral stones (OR = 15.7; 95% CI = 2.2-115, p = 0.007). Our study revealed that the most significant risk factor for urosepsis caused by kidney and ureteral stones was the patients' poor PS.

Predictive value of ureteral wall thickness (UWT) assessment on the success of internal ureteral stent insertion in cases with obstructing ureteral calculi.

To evaluate the possible role of ureteral wall thickness (UWT) assessment in the prediction of the success for stent placement in cases with obstructing ureteric stones. 227 adult patients with a single unilateral obstructing ureteral stone requiring internal ureteral stent placement were included. In addition to stone size, the ureteric wall thickness at the impacted stone site and the degree of hydronephrosis were also assigned on CT images. Patients were divided into two subgroups: Group 1: patients in whom internal ureteral stent could not be passed beyond the stone and Group 2: patients in whom an internal ureteral stent was passed successfully. The possible relationship between the UWT values and the success of stent placement, degree of hydronephrosis were comparatively evaluated. The majority of the stones were located in the proximal ureter in Group 1 and the degree of hydronephrosis was also higher in these cases. Moreover, while the mean value of UWT calculated on CT images was 4.3 ± 0.9 mm in Group 1, this value was noted to be 2.5 ± 0.8 mm in cases of group 2. A cutoff UWT value of 3.35 mm was highly predictive for the stent insertion and cases with higher values required additional procedures or percutaneous nephrostomy tube placement. UWT value calculated at the obstructing stone site was found to be predictive enough for the likelihood of internal ureteral stent passage with high sensitivity and specificity. This evaluation may enable the urologist to make the best decision for urinary diversion in such cases.

Assessment of trends and clinical presentation in the emergency department of patients with renal colic during the COVID-19 pandemic era. / Evaluación de las tendencias y presentación clínica de pacientes con cólico nefrítico que acuden al servicio de urgencias durante la era pandémica del COVID-19.

INTRODUCTION: We hypothesized that the recent COVID-19 pandemic may lead to a delay in renal colic patients presenting to the Emergency Department due to the fear of getting infected. This delay may lead to a more severe clinical condition at presentation with possible complications for the patients. MATERIAL AND METHODS: Retrospective review of data collected from three institutions from Spain and Italy. Patients who presented to Emergency Department with unilateral or bilateral renal colic caused by imaging confirmed urolithiasis during the 45 days before and after each national lockdown were included. Data collected included patients' demographics, biochemical urine and blood tests, radiological tests, signs, symptoms and the therapeutic management. Analysis was performed between two groups, Group A: patients presenting prior to the national lockdown date; and Group B: patients presenting after the national lockdown date. RESULTS: A total of 397 patients presented to Emergency Department with radiology confirmed urolithiasis and were included in the study. The number of patients presenting to Emergency Department with renal/ureteric colic was 285 (71.8%) patients in Group A and 112 (28.2%) patients in Group B (p<0.001). The number of patients reporting a delay in presentation was 135 (47.4%) in Group A and 63 (56.3%) in Group B (p=0.11). At presentation, there were no statistical differences between Group A and Group B regarding the serum creatinine level, C reactive protein, white blood cell count, fever, oliguria, flank pain and hydronephrosis. In addition, no significant differences were observed with the length of stay, Urology department admission requirement and type of therapy. CONCLUSION: Data from our study showed a significant reduction in presentations to Emergency Department for renal colic after the lockdown in Spain and Italy. However, we did not find any significant difference with the length of stay, Urology department admission requirement and type of therapy.

Quick Sequential (Sepsis Related) Organ Failure Assessment: A high performance rapid prognostication tool in patients having acute pyelonephritis with upper urinary tract calculi.

Purpose: To analyze the utility of quick Sequential Organ Failure Assessment (qSOFA) in patients with uro-sepsis due to acute pyelonephritis (APN) with upper urinary tract calculi, we conducted this study. The role of qSOFA as a tool for rapid prognostication in patients with sepsis is emerging. But there has been a great debate on its utility. Literature regarding utility of qSOFA in uro-sepsis is scarce. Materials and Methods: Ours was a retrospective study including 162 consecutive patients who were admitted for APN with upper urinary tract calculi over a 3 and half years (total 42 months) period. We evaluated the accuracy of qSOFA in predicting inhospital mortality and intensive care unit (ICU) admissions and compared this with the predictive accuracy of systemic inflammatory response syndrome (SIRS). We used the Area Under Curve (AUC) of the Receiver Operator Characteristic curve to calculate it and also calculated the optimum cut off for qSOFA score. Results: The overall mortality and ICU admission rates were 7.4% and 12.9%, respectively. qSOFA had a higher predictive accuracy for in-hospital mortality (AUC, 0.981; 95% confidence interval [CI], 0.962-1.000) and ICU admissions (AUC, 0.977; 95% CI, 0.955-0.999) than SIRS. A qSOFA score of ≥2 was an optimum cut off for predicting prognosis. In a multivariate model qSOFA ≥2 was a highly significant predictor of in-hospital mortality and ICU admissions (p<0.001). Conclusions: qSOFA is a reliable and rapid bedside tool in patients with sepsis with accuracy more than SIRS in predicting inhospital mortality and ICU admissions.

The ability of a limited metabolic assessment to identify pediatric stone formers with metabolic abnormalities.

INTRODUCTION: American Urological Association guidelines recommend a urinary metabolic evaluation after the first stone event in all pediatric stone patients. Prior studies identified hypercalciuria and urine hypovolemia as the most common abnormalities in children with urolithiasis. Recent data suggest that hypocitraturia is most prevalent. It was hypothesized that a limited evaluation would detect the majority of clinically significant metabolic abnormalities in pediatric stone formers. MATERIAL AND METHODS: A retrospective analysis of all children (<18 years of age) with renal/ureteral calculi evaluated at the study institution from 2005 to 2015 was performed. Children with ≥ one 24-h urinary metabolic profile after a clinical visit for renal/ureteral calculi were included. Those with bladder stones and those with undercollection or overcollection or missing urinary creatinine were excluded. Demographics and data from the first urinary metabolic profile and stone analyses were collected. The sensitivity, specificity, and positive and negative predictive value (NPV) of a limited urinary metabolic evaluation consisting of four parameters (24-h calcium, citrate, and oxalate and low urinary volume) were compared to a complete urinary metabolic profile. The number and type of metabolic abnormalities that would have been missed with this limited evaluation weredetermined. RESULTS: Of 410 patients, 21 were excluded for age ≥18 years, 13 for bladder stones, 248 for overcollections, 38 for undercollections, and 10 for missing creatinine. This left 80 patients for inclusion: median age 11.4 years, 60% female, and 96.3% white. Of the entire cohort, 69.6% had hypocitraturia, 52.5% had low urine volume, and 22.5% had hypercalciuria. Sensitivity was 87.5%. Specificity could not be calculated because no patients had a normal complete metabolic evaluation. The NPV was zero, and the positive predictive value was 100%, but these are artifacts resulting from the absence of patients with a normal complete metabolic evaluation. Of the 80 patients, 10 had at least one abnormality missed by a limited metabolic evaluation (Table 1). The missed abnormalities were high pH (n = 6), abnormal 24-h phosphorus (low in 1 patient and high in 1 patient), low 24-h magnesium (n = 3), low 24-h potassium (n = 3), and high 24-h sodium (n = 4). DISCUSSION: A limited urinary metabolic evaluation would have detected the vast majority of clinically significant metabolic abnormalities in the study sample. Approximately two-thirds of the study patients submitted inadequate 24-h urine specimens. CONCLUSIONS: A simplified approach to metabolic evaluation in first-time stone formers with a stone analysis available was proposed. This streamlined approach could simplify the metabolic evaluation and reduce health care costs.

Radiological noninvasive assessment of ureteral stone impaction into the ureteric wall: A critical evaluation with objective radiological parameters.

PURPOSE: To determine the predictive value of certain radiological parameters for an objective asssessment of the presence of ureteral stone impaction. MATERIALS AND METHODS: Seventy-nine patients with a single proximal ureteral stones were retrieved from the departmental database. Both clinical and particularly radiological data of all cases were well evaluated on this aspect. In addition to the time period between the first colic attack and definitive management; diameter of proximal ureter and renal pelvis, longitudinal and transverse stone size, Hounsfied unit (HU) of the stone and lastly ureteral wall thickness at the impacted stone site were all carefully evaluated and noted. RESULTS: Patients had a single proximal ureteral stone. While mean age of the cases was ranged 20 to 78 years; mean stone size was 15.62±4.26 mm. Evaluation of our data demonstrated that although there was a statistically significant correlation between ureteral wall thickness and patients age, transverse diameter of the stone, ureteral diameter just proximal to the stone, renal pelvic diameter and the duration of renal colic attacks; no correlation could be demonstrated between patients sex and the HU of the stone. CONCLUSIONS: Prediction of the presence and degree of proximal ureteral stone impaction is a challenging issue and our data indicated a highly significant correlation between ureteral wall thickness and the some certain radiological as well as clinical parameters evaluated which will give an objective information about the presence of impaction which may in turn be helpful in the follow-up and also management plans of such calculi.

A survey of patient preferences regarding medical expulsive therapy following the SUSPEND trial.

INTRODUCTION: Several recent trials have reported limited benefit for medical expulsive therapy (MET) in terms of stone passage rates, analgesic requirements, or need for intervention. We evaluated patient attitudes regarding MET after explaining these new findings. MATERIALS AND METHODS: Over a 12 week period, an investigator-designed survey was offered to sequential patients during routine appointments in our urologic clinic. A brief summary of the conflicting data for MET was provided. Patients then answered questions about their attitudes toward using MET. RESULTS: Patients (n = 200; 103 M, 97 F) were 56 ± 14 years old (range 20-103 years) and were mostly being seen for management of kidney stones (88%). Forty-nine percent reported they would try tamsulosin despite the new data; 26% said they would not, and 25% were unsure. Of patients indicating they would take tamsulosin, 35% stated they would also be willing to take steroids. Thirty-five percent of patients said they were willing to pay the full price of tamsulosin if needed. Seventy-one percent said they would prefer to try medical therapy prior to pursuing surgical therapy, again, despite new evidence regarding the efficacy of MET. CONCLUSION: In this initial report of patient attitudes about MET after SUSPEND trial results, we found that nearly half of patients would still try MET and that the vast majority of patients prioritize medical over surgical therapy when possible. As new research emerges, ways to translate this information to patients and to assess their attitudes and perceptions should be developed.

Medical expulsive therapy in adults with ureteric colic: a multicentre, randomised, placebo-controlled trial.

BACKGROUND: Meta-analyses of previous randomised controlled trials concluded that the smooth muscle relaxant drugs tamsulosin and nifedipine assisted stone passage for people managed expectantly for ureteric colic, but emphasised the need for high-quality trials with wide inclusion criteria. We aimed to fulfil this need by testing effectiveness of these drugs in a standard clinical care setting. METHODS: For this multicentre, randomised, placebo-controlled trial, we recruited adults (aged 18-65 years) undergoing expectant management for a single ureteric stone identified by CT at 24 UK hospitals. Participants were randomly assigned by a remote randomisation system to tamsulosin 400 µg, nifedipine 30 mg, or placebo taken daily for up to 4 weeks, using an algorithm with centre, stone size (≤5 mm or >5 mm), and stone location (upper, mid, or lower ureter) as minimisation covariates. Participants, clinicians, and trial personnel were masked to treatment assignment. The primary outcome was the proportion of participants who did not need further intervention for stone clearance within 4 weeks of randomisation, analysed in a modified intention-to-treat population defined as all eligible patients for whom we had primary outcome data. This trial is registered with the European Clinical Trials Database, EudraCT number 2010-019469-26, and as an International Standard Randomised Controlled Trial, number 69423238. FINDINGS: Between Jan 11, 2011, and Dec 20, 2013, we randomly assigned 1167 participants, 1136 (97%) of whom were included in the primary analysis (17 were excluded because of ineligibility and 14 participants were lost to follow-up). 303 (80%) of 379 participants in the placebo group did not need further intervention by 4 weeks, compared with 307 (81%) of 378 in the tamsulosin group (adjusted risk difference 1·3% [95% CI -5·7 to 8·3]; p=0·73) and 304 (80%) of 379 in the nifedipine group (0·5% [-5·6 to 6·5]; p=0·88). No difference was noted between active treatment and placebo (p=0·78), or between tamsulosin and nifedipine (p=0·77). Serious adverse events were reported in three participants in the nifedipine group (one had right loin pain, diarrhoea, and vomiting; one had malaise, headache, and chest pain; and one had severe chest pain, difficulty breathing, and left arm pain) and in one participant in the placebo group (headache, dizziness, lightheadedness, and chronic abdominal pain). INTERPRETATION: Tamsulosin 400 µg and nifedipine 30 mg are not effective at decreasing the need for further treatment to achieve stone clearance in 4 weeks for patients with expectantly managed ureteric colic. FUNDING: UK National Institute for Health Research Health Technology Assessment Programme.

Assessment of ureterovesical jet dynamics in obstructed ureter by urinary stone with color Doppler and duplex Doppler examinations.

This study was designed to evaluate ureterovesical jet dynamics in obstructed ureter and to compare it with those of contralateral unobstructed side. Forty-six patients with diagnosis of ureteral stone, based on imaging findings in computed tomography were enrolled in this study. The gray-scale ultrasound exam from both kidneys and urinary bladder was performed. Then, ureterovesical jet characteristics including ureteral jet frequency, duration and peak velocity were assessed by color Doppler and duplex Doppler studies in both obstructed and unobstructed ureters by a radiologist, 15-30 min after oral hydration with 750-1,000 mL of water. When compared with contralateral normal side, the ureterovesical jet in obstructed ureter showed less frequency (0.59 vs. 3.04 jets/min; P < 0.05), shorter duration (1.24 vs. 5.26 s; P < 0.05) and lower peak velocity (5.41 vs. 32.09 cm/s; P < 0.05). The cut-off points of 1.5 jets/min, 2.5 s and 19.5 cm/s for difference of ureteral jet frequency, duration and peak velocity between obstructed and contralateral normal ureters yielded sensitivities of 97.8, 95.6 and 100 % and specificities of 87, 87.9 and 97.8 %, respectively for diagnosis of ureteral obstruction. Given the safety of Doppler study and significant differences in flow dynamics of obstructed versus unobstructed ureters, our findings demonstrated the utility of Doppler ultrasound examination as a useful adjunct to gray-scale ultrasound by improving the accuracy of ultrasound exam in diagnosis of ureteral obstruction.

Prevalence and management of complications of ureteroscopy: a seven-year experience with introduction of a new maneuver to prevent ureteral avulsion.

PURPOSE: To evaluate the prevalence and type of rigid ureteroscopy complications and suggest a new method for ureteral avulsion prevention. MATERIALS AND METHODS: Between March 2002 and March 2009, we retrospectively evaluated 2955 patients who had undergone diagnostic or therapeutic ureteroscopy for asymptomatic hematuria, migrated ureteral stent, or transurethral lithotripsy. They were enrolled from four hospitals in Ahvaz, Iran. RESULTS: Complications were encountered in 241 (8%) patients, including transient hematuria (4.2%), mucosal erosion (1.4%), stone migration (1.3%), ureteral perforation (1.2%), and fever and/or sepsis (1.0%). Ureteral avulsion occurred in 6 (0.2%) patients. Mostly, complications were managed conservatively, using ureteral stenting. Ureteral avulsions were managed using a new technique. CONCLUSION: In our series, the complication rate is comparable with the literature. A new technique was used in case of ureteroscope entrapment in the ureter, to lessen the occurrence of ureteral avulsion.

A randomized prospective controlled study for assessment of different ureteral occlusion devices in prevention of stone migration during pneumatic lithotripsy.

OBJECTIVE: To compare the safety and efficacy of two different ureteral occlusion devices (stone cone and entrapment net) in preventing retrograde stone migration during ureteroscopic pneumatic lithotripsy. Proximal migration of stone fragments during ureteroscopic lithotripsy is a common problem, especially when the pneumatic lithotripter is used for stone fragmentation. PATIENTS AND METHODS: A total of 195 patients with proximal ureteric stones were prospectively randomized into one of three groups in this study, with 65 patients in each group. In group I, the Stone Cone was used as a ureteral occlusive device; in group II, the N-Trap was used; and in group III (control group), the patients underwent pneumatic lithotripsy without any ureteral occlusive device. RESULTS: The ureteroscopic procedure was completed successfully in 180 patients; 63 patients in group I, 59 patients in group II, and 58 patients in group III. Patients in group I showed significantly lower incidence of stone migration compared with the other 2 groups (P <.05). Both ureteral occlusive devices significantly lowered the incidence of residual fragments (>3 mm), ureteral trauma, operative time, and the need for ureteral stenting compared with control group. The stone-free rate at 3 weeks was 95.24%, 83.05%, and 72.41% in groups I, II, and III, respectively. The patients in group I had a statistically significant stone-free rate compared with the other two groups (P <.05). Auxiliary procedures were required in 3 (4.76%), 10 (16.94%), and 16 cases (27.58%) in groups I, II, and III, respectively. CONCLUSION: The use of Stone Cone or N-Trap is valuable during ureteroscopic pneumatic lithotripsy for treatment of proximal ureteral stones. Both devices significantly diminish residual fragments, the incidence of ureteral wall trauma, and the need for the auxiliary procedure. However, the stone cone was more effective in preventing proximal stone migration and the subsequent stone-free rate.

Percutaneous nephrolithotomy for proximal ureteral calculi with severe hydronephrosis: assessment of different lithotriptors.

PURPOSE: We compared the efficacy and safety of percutaneous nephrolithotomy (PCNL) with different intracorporeal lithotriptors for proximal ureteral stones in patients with severe hydronephrosis. PATIENTS AND METHODS: We retrospectively analyzed the records of 192 patients with proximal ureteral calculi and severe hydronephrosis who underwent PCNL between February 2003 and December 2007. Calculi were fragmented with a pneumatic lithotriptor in 44 patients (group 1), Swiss Lithoclast Master in 54 (group 2), low-power holmium:yttrium-aluminum-garnet (YAG) laser in 56 (group 3) and high-power holmium:YAG laser in 38 (group 4). Patients were assessed about 12 months postoperatively with intravenous urography and ultrasonography for late complications. Stone size, operative time, stone-free rate, and follow-up were analyzed in each group. RESULTS: Mean stone size for different groups were 16.2 +/- 2.8 mm, 16.6 +/- 2.1 mm, 16.0 +/- 2.7 mm, and 16.4 +/- 1.1 mm, respectively. Average operative time for different groups were 118 +/- 17 minutes, 81 +/- 10 minutes, 85 +/- 14 minutes, 110 +/- 16 minutes, respectively. Group 2 and group 3 showed superior outcomes of shorter operative time (P = 0.000). The overall stone-free rate was 86.5%. As stratified by lithotriptors, the stone-free rate was 81.8% in group 1, 92.9% in group 2, 88.9% in group 3, and 78.9% in group 4 (P = 0.190). No significant difference was found among the groups in terms of blood loss and postoperative hospital stay. Repeated PCNL or shockwave lithotripsy was necessary as an auxiliary procedure in 26 patients. The overall complication rate was 18.2%; most complications were minor and insignificant. During the follow-up, ureteral stricture developed in 10 patients and new renal stones developed in 4 patients. CONCLUSIONS: PCNL combined with Swiss Lithoclast Master or low-power holmium:YAG laser is the preferred endourologic modality for the management of proximal ureteral calculi in patients with severe hydronephrosis.

Unenhanced helical computed tomography vs intravenous urography in patients with acute flank pain: accuracy and economic impact in a randomized prospective trial.

Unenhanced helical computed tomography (UHCT) has evolved into a well-accepted alternative to intravenous urography (IVU) in patients with acute flank pain and suspected ureterolithiasis. The purpose of our randomized prospective study was to analyse the diagnostic accuracy of UHCT vs IVU in the normal clinical setting with special interest on economic impact, applied radiation dose and time savings in patient management. A total of 122 consecutive patients with acute flank pain suggestive of urolithiasis were randomized for UHCT ( n=59) or IVU ( n=63). Patient management (time, contrast media), costs and radiation dose were analysed. The films were independently interpreted by four radiologists, unaware of previous findings, clinical history and clinical outcome. Alternative diagnoses if present were assessed. Direct costs of UHCT and IVU are nearly identical (310/309 Euro). Indirect costs are much lower for UHCT because it saves examination time and when performed immediately initial abdominal plain film (KUB) and sonography are not necessary. Time delay between access to the emergency room and start of the imaging procedure was 32 h 7 min for UHCT and 36 h 55 min for IVU. The UHCT took an average in-room time of 23 min vs 1 h 21 min for IVU. Mild to moderate adverse reactions for contrast material were seen in 3 (5%) patients. The UHCT was safe, as no contrast material was needed. The mean applied radiation dose was 3.3 mSv for IVU and 6.5 mSv for UHCT. Alternative diagnoses were identified in 4 (7%) UHCT patients and 3 (5%) IVU patients. Sensitivity and specificity of UHCT and IVU was 94.1 and 94.2%, and 85.2 and 90.4%, respectively. In patients with suspected renal colic KUB and US may be the least expensive and most easily accessable modalities; however, if needed and available, UHCT can be considered a better alternative than IVU because it has a higher diagnostic accuracy and a better economic impact since it is more effective, faster, less expensive and less risky than IVU. In addition, it also has the capability of detecting various additional renal and extrarenal pathologies.

Ultrasound vs CT for the detection of ureteric stones in patients with renal colic.

The aim of our study was to compare the accuracy of non-contrast spiral CT with ultrasound (US) for the diagnosis of ureteral calculi in the evaluation of patients with acute flank pain. 62 consecutive patients with flank pain were examined with both CT and US over a period of 9 months. All patients were prospectively defined as either positive or negative for ureterolithiasis, based on follow-up evaluation. 43 of the 62 patients were confirmed as having ureteral calculi based on stone recovery or urological interventions. US showed 93% sensitivity and 95% specificity in the diagnosis of ureterolithiasis; CT showed 91% and 95%, respectively. Pathology unrelated to urinary stone disease was demonstrated in six patients. Although both modalities were excellent for detecting ureteral stones, consideration of cost and radiation lead us to suggest that US be employed first and CT be reserved for when US is unavailable or non-diagnostic.

Randomized prospective comparison of non-contrast enhanced helical computed tomography and intravenous urography in the diagnosis of acute ureteric colic.

Non-contrast enhanced helical CT has become an accepted technique for evaluating acute ureteric colic. The results of a randomized prospective comparison of the accuracy, cost and radiation dose of CT and intravenous urography (IVU) are presented. All patients presenting to the Emergency Department with symptoms and signs suggestive of ureteric colic over a 16-month period (n = 242) were randomized to CT or IVU. Follow up was obtained for 228 patients (94%), with 14 patients (6%) lost to follow up. One hundred and twenty-three patients (54%) underwent CT and 105 (46%) had an IVU. At follow up the sensitivity and specificity of CT were each 100%, while those of IVU were 99% and 100%, respectively. Computed tomography demonstrated seven of 26 (27%) potential alternative diagnoses, whereas IVU suggested one of 23 (4%). Estimates of the average effective dose were calculated for CT (4.95 mSv) and IVU (1.48 mSv, 95% confidence interval (CI) 0.7-2.27). Radiation dose and intravenous contrast material safety are discussed and the relative costs are considered. Computed tomography is as accurate as IVU in the diagnosis of acute ureteric colic. It confers certain major diagnostic benefits, and is a fast, well-tolerated technique. Its accompanying higher effective radiation dose is recognized.

Unenhanced helical computed tomography for the evaluation of suspected renal colic in the adolescent population: a pilot study.

OBJECTIVES: Unenhanced helical computed tomography (UHCT) is rapidly becoming the preferred imaging modality for the evaluation of suspected renal colic in the adult population; however, a series addressing its use in the adolescent population has not been previously published. We assessed the utility of UHCT in the evaluation of suspected renal colic in this age group. METHODS: Seventeen patients between the ages of 8 and 18 years (mean 14.7) presented to the emergency departments of four hospitals for evaluation of suspected renal colic. All patients were studied with UHCT immediately after initial evaluation. A single helical acquisition was performed from the midpoint of T-12 vertebra to a point below the bladder base, using a slice thickness of 5 mm. Films were reviewed by the institutional radiologist, and results were quantified. RESULTS: Of the 17 patients who underwent evaluation, no abnormality was detected in 8 patients. A stone was localized in 7 patients who were then appropriately treated. One patient had no stone visualized, but secondary signs suggested a recently passed stone. The final patient had no stone; however, marked bilateral hydroureteronephrosis was noted that led to further evaluation. A single phlebolith was seen in only 1 patient, and no study was nondiagnostic. CONCLUSIONS: UHCT is a safe, rapidly performed test for the evaluation of suspected renal colic in adolescents. It is highly sensitive and specific for renal and ureteral calculi and, more importantly, allows visualization of alternate pathology. In addition, secondary signs are seen that aid in determining obstruction and are helpful if no stone is visualized. Phleboliths, which can simulate a stone, are rarely seen in adolescence. We believe UHCT allows for rapid triage and localization of stones and should be recommended as the primary diagnostic modality for the evaluation of adolescents with suspected renal colic.

Can noncontrast helical computed tomography replace intravenous urography for evaluation of patients with acute urinary tract colic?

The objective of this study was to determine whether helical computed tomography (CT) performed without oral or intravenous contrast agents is accurate in the evaluation of patients with suspected acute renal colic. One hundred consecutive patients with suspected renal colic or ureteral colic were referred by our institution's emergency department for unenhanced helical CT scans. We reviewed the original radiographic report for each patient and recorded the size and location of ureteral calculi and other concurrent urinary tract calculi, if any. We also recorded the presence or absence of hydronephrosis, hydroureter, perinephric edema, and periureteral edema. A total of 49 patients had ureteral calculi, 17 patients had only renal calculi, and 34 patients had no stones. Forty-nine patients had ureteral calculi, and 40 (82%) of these 49 patients had associated CT signs including hydroureter and periureteral edema. Calculi were present in the proximal ureter in 11 patients, the midureter in seven patients, and the distal ureter including ureterovesical junction in 31 patients. Calculi were seen elsewhere in the urinary tract and renal pelvis in 44 patients. Other diagnostic tests and stone passage were used to confirm the CT diagnosis of ureteral stones. The sensitivity and specificity of helical CT in evaluating ureteral calculi were 100% and 94%, respectively. Sixteen extraurinary lesions were detected in 34 patients who had no urinary calculi. Most extraurinary lesions (81%) were deemed the cause of acute flank pain. The room time for CT averaged 26 min, compared to 69 min for intravenous urography (IVU). The charge for CT was $600 compared to $400 for IVU in our institution. Unenhanced helical CT was fast and accurate in determining the cause of colic and proved to be highly accurate for emergency situations.

Optimal method of urgent decompression of the collecting system for obstruction and infection due to ureteral calculi.

PURPOSE: We compare the efficacy of percutaneous nephrostomy with retrograde ureteral catheterization for renal drainage in cases of obstruction and infection associated with ureteral calculi. MATERIALS AND METHODS: We randomized 42 consecutive patients presenting with obstructing ureteral calculi and clinical signs of infection (temperature greater than 38 C and/or white blood count greater than 17,000/mm.3) to drainage with percutaneous nephrostomy or retrograde ureteral catheterization. Preoperative patient and stone characteristics, procedural parameters, clinical outcomes and costs were assessed for each group. RESULTS: Urine cultures obtained at drainage were positive in 62.9% of percutaneous nephrostomy and 19.1% of retrograde ureteral catheterization patients. There was no significant difference in the time to treatment between the 2 groups. Procedural and fluoroscopy times were significantly shorter in the retrograde ureteral catheterization (32.7 and 5.1 minutes, respectively) compared with the percutaneous nephrostomy (49.2 and 7.7 minutes, respectively) group. One treatment failure occurred in the percutaneous nephrostomy group, which was successfully salvaged with retrograde ureteral catheterization. Time to normal temperature was 2.3 days in the percutaneous nephrostomy and 2.6 in the retrograde ureteral catheterization group, and time to normal white blood count was 2 days in the percutaneous nephrostomy and 1.7 days in the retrograde ureteral catheterization group (p not significant). Length of stay was 4.5 days in the percutaneous nephrostomy group compared with 3.2 days in the retrograde ureteral catheterization group (p not significant). Cost analysis revealed that retrograde ureteral catheterization was twice as costly as percutaneous nephrostomy. CONCLUSIONS: Retrograde ureteral catheterization and percutaneous nephrostomy effectively relieve obstruction and infection due to ureteral calculi. Neither modality demonstrated superiority in promoting a more rapid recovery after drainage. Percutaneous nephrostomy is less costly than retrograde ureteral catheterization. The decision of which mode of drainage to use may be based on logistical factors, surgeon preference and stone characteristics.

Assessment of painful ureterohydronephrosis during pregnancy by MR urography.

The purpose of this study was to assess the value of the fast imaging sequence called RARE (rapid acquisition with relaxation enhancement) MR urography (or RMU) in pregnant women with painful ureterohydronephrosis. A total of 17 pregnant women with an acute flank pain were examined with RMU. Results were compared with those of US, X-rays and the evolution of symptoms. The gold standard techniques used to evaluate the results of MR urography were US when it showed the entire dilated urinary tract and the nature of the obstruction (9 cases), limited intravenous urography (IVU) when performed (3 cases) or endoscopic procedure (5 cases). The accuracy of RMU in the detection of urinary tract dilatation and the localization of the level of obstruction was excellent (sensitivity 100% in our series). The determination of the type of obstruction, intrinsic vs extrinsic, was always exact. The RMU technique alone could not specify the exact nature of the obstruction. The RMU technique is able to differentiate a physiological from a pathological ureterohydronephrosis during pregnancy. It could be considered as the procedure of choice when US failed to establish the differential diagnosis.