Renal Colic in Pregnancy: Lithiasis or Physiological Hydronephrosis?

Establishment of a diagnostic model for urinary calculi in pregnant women: A retrospective cohort study

OBJECTIVE

The diagnosis of symptomatic urinary stones during pregnancy is challenging; ultrasonography has a low specificity and sensitivity for diagnosing urinary stones. This study aimed to develop a clinical diagnostic model to assist clinicians in distinguishing symptomatic urinary stones in pregnant women.

METHODS

In this retrospective cohort study, we consecutively collected clinical data from pregnant women who presented with acute abdominal, lumbar, and lumbar and abdominal pain at the emergency department of our hospital between January 1, 2017, and December 31, 2019. To distinguish patients with urinary calculi from those without, we reviewed the follow-up records within 2 weeks post-consultation, ultrasonography results within 2 weeks, or self-reports of stone passage within 2 weeks. We selected risk factors from the baseline clinical and laboratory data of patients to establish a diagnostic model.

RESULTS

Of the total patients included in the study, 105 patients were diagnosed as having symptomatic urinary stones and 126 were determined to have abdominal pain for reasons other than urinary stones. The initial model had an area under the curve (AUC) of 0.9966. The No-Lab Model had an AUC of 0.9856. The Lab Model had an AUC of 0.832. The Stone Model had an AUC of 0.9952. The simplified Stone Model did not show a decrease in discriminative ability.

CONCLUSION

Of the four diagnostic models that we established for preliminary diagnosis of symptomatic urinary tract stones in pregnant women, the simplified Stone Model demonstrated excellent performance. Users can scan quick response codes to access web-based diagnostic model interfaces, facilitating easy clinical operation.

Has the COVID-19 pandemic affected ureteral stone management in pregnant women? A retrospective single-center study

INTRODUCTION

This study aimed to evaluate the effect of coronavirus disease (COVID-19) on the patients' referral in the pregnant population and also investigate each treatment approach's advantages and disadvantages for acute renal colic in pregnancy.

METHODS

In this retrospective study, we included all pregnant women with ureteral stones referred to a referral center between January 2019 and March 2021.

RESULTS

Among 53 pregnant women, 18 (33.9%) were on conservative therapy, which passed the stone without any complications. Double J stent or nephrostomy tube insertion was done for 24 patients (45.2%). Seventeen of these patients (70.8%) presented post-surgical complications, including hematuria (29.2%), pyelonephritis (20.8%), and lower urinary tract symptoms (20.8%). Transurethral lithotripsy (TUL) was done in 11 patients (20.7%). Only one of these patients developed hematuria following TUL. Thus, in our population study, double J stent or nephrostomy insertion was associated with a higher chance of postoperative complications than TUL (p-value = 0.001). Thirty-six patients were referred within 13 months before the entry of COVID-19, while 17 were referred during a similar approximate duration after the COVID-19 entry into the country. Only the initial presentation had a significant difference between these two periods (p-value = 0.034).

CONCLUSIONS

When conservative treatment fails, we recommend TUL as the second-line treatment over temporary procedures, such as double J stent or nephrostomy insertion. Of note, in a group of patients with an emergent clinical setting, including active infection, deteriorating renal function, signs of preterm labor, solitary kidney, etc., double J or nephrostomy tube insertion remains the preferred management method for its fast resolution of obstruction and infection. Besides, a decrease in visits with an increase in complicated cases after COVID-19 was observed, maybe due to a delay in referring.

Factors predicting the need for surgical intervention for hydronephrosis during pregnancy: a systematic review of the literature

PURPOSE

Symptomatic hydronephrosis in pregnancy can cause both maternal and obstetric complications. In various studies, factors predicting the need for surgical intervention have been evaluated, however these factors have not been systematically assessed yet. This systematic review analyzes published studies about hydronephrosis during pregnancy and determines the predictive factors for the need for surgical intervention for hydronephrosis during pregnancy.

MATERIALS AND METHODS

A systematic review was conducted in January 2023 using the Medline, Web of Science and ScienceDirect/Scopus databases according to PRISMA guidelines. We searched these databases with the following search strategy: (intervention OR nephrostomy OR stent insertion) AND (pregnancy hydronephrosis).

RESULTS

The literature review revealed 2461 potentially eligible studies. After the screening, six studies were enrolled in this review. High neutrophil-to-lymphocyte ratio, high C-reactive protein level, high white blood cell count, high creatinine levels, fever, persistent pain for more than 4 days, presence of ureteral stones more than 8 mm, high grade hydronephrosis, high fetal body weight and high delta resistive index were reported to be related with the need for surgical intervention.

CONCLUSION

The rate of symptomatic hydronephrosis and requirement for surgical intervention is low during pregnancy. However, as symptomatic hydronephrosis may cause serious obstetric complications, it is important to know the parameters that can predict patients who may need surgical intervention. These results will assist gynecologists and urologists to stratify pregnant women for surgical intervention.

Safety and Efficacy of Ureteroscopic Laser Lithotripsy in the Management of Ureteric Calculi in Pregnancy-Experience of a Tertiary Care Center

Introduction

Ureteric colic in pregnancy is one of the common non-obstetric reasons for emergency department visits. Ureteric calculi present a significant threat to maternal and fetal health and definitive management often becomes necessary. Our aim is to assess the safety and efficacy of ureteroscopic laser lithotripsy in the management of ureteric stones in pregnancy.

Material and methods

This is a prospective observational study of 3 years carried at a tertiary referral center. It includes all pregnant patients who underwent ureteroscopic laser lithotripsy for ureteric stones.

Results

A total of 29 pregnant patients underwent ureteroscopic laser lithotripsy at our center in 3 years. The mean age of patients was 33.5 ± 6.2 years, and the mean gestation age at the time of ureteroscopy was 23.34 ± 5.9 weeks. The average stone size was 8.3 ± 3.6 mm and was predominantly found in upper ureter (62%). The mean operative time was 31 ± 8.9 min, and the average laser energy spent was 4.3 ± 1.1 kJ/case. There was no major Intraoperative complication, and the average hospital stay was 2.5 ± 1.5 days. Complete stone clearance was achieved in 93.1% of cases.

Conclusion

Ureteroscopic laser lithotripsy is safe and effective treatment of ureteric stones in terms of obstetric outcome and stone clearance in pregnancy.

Ureterorenoscopy for stone disease in pregnancy: a literature review and update

PURPOSE OF REVIEW

Management of stone disease in pregnancy poses a challenge for all healthcare professionals involved in their care. During pregnancy, there is an increase in the incidence of urolithiasis. Major technological and procedural advances have been seen in the last decade for endoscopic management of urolithiasis. The purpose of this review is to provide a comprehensive workup of available literature on use of ureteroscopy for stone treatment during pregnancy.

RECENT FINDINGS

We identified 268 articles on screening, of which 28 were included in the final review. Overall adverse event rates were low, with no severe complications reported in the included studies. On multivariate analysis, the only significant correlation was an inverse relationship between calculated caseload and adverse obstetric events. No further correlation could be found between caseload, operation technique and adverse event rates. Data quality was low among the included studies.

SUMMARY

While ureteroscopy is a relatively safe and effective option for active stone treatment during pregnancy, they should be performed in experienced endourology centres in conjunction with obstetric teams.

Imaging of Acute Abdominopelvic Pain in Pregnancy and Puerperium-Part II: Non-Obstetric Complications

Emergency imaging in pregnancy and puerperium poses unique challenges both for clinicians and radiologists, requiring timely and accurate diagnosis. Delay in treatment may result in poor outcomes for both the patient and the foetus. Pregnant and puerperal patients may present in the emergency setting with acute abdominopelvic pain for various complications that can be broadly classified into obstetric and non-obstetric related diseases. Ultrasonography (US) is the primary diagnostic imaging test; however, it may be limited due to the patient's body habitus and the overlapping of bowel loops. Computed tomography (CT) carries exposure to ionising radiation to the foetus, but may be necessary in selected cases. Magnetic resonance imaging (MRI) is a valuable complement to US in the determination of the etiology of acute abdominal pain and can be used in most settings, allowing for the identification of a broad spectrum of pathologies with a limited protocol of sequences. In this second section, we review the common non-obstetric causes for acute abdominopelvic pain in pregnancy and post partum, offering a practical approach for diagnosis and pointing out the role of imaging methods (US, MRI, CT) with the respective imaging findings.

A comparison of adverse pregnancy events between ureteral stents and percutaneous nephrostomy tubes in the treatment of nephrolithiasis during pregnancy: A propensity score-matched analysis of a large multi-institutional research network

PURPOSE

To investigate rates of adverse pregnancy events associated with the use of percutaneous nephrostomy tubes (PCN) versus ureteral stents in the treatment of nephrolithiasis during pregnancy.

METHODS

We queried the TriNetX Diamond Network database to evaluate pregnant women (ICD-10 Z34, O09) with a history of nephrolithiasis (N20-23) who underwent a PCN (CPT 50432) or ureteral stent (52332) placement up to 6 months before delivery (O80-82). We controlled for the following potentially confounding variables through propensity score matching: age, race, ethnicity, acute pyelonephritis (N10), infections of the genitourinary tract in pregnancy (O23.0), and other sepsis (A41) at the time of stent or PCN placement.

RESULTS

We identified 2,999 pregnant women who underwent ureteral stent placement and 321 who underwent PCN. Following propensity score matching, we found there to be no significant difference in the rate of premature labor or delivery (aOR 1.08, 95% CI 0.735-1.588), premature rupture of membranes (0.889, 0.453-1.743), intrauterine infection (0.906, 0.379-2.165), or c-Sect. (0.825, 0.408-1.667). Within 6 months of their initial procedure, women with a ureteral stent experienced a significantly decreased rate of subsequent urinary tract infection (UTI) or pyelonephritis (0.52, 0.38-0.71), inpatient hospital stay (0.40, 0.26-0.64), emergency department visit (0.65, 0.48-0.89), and repeat exchange procedure (0.70, 0.51-0.96).

CONCLUSION

In the treatment of nephrolithiasis during pregnancy, PCN versus ureteral stent placement does not confer a significant difference in rates of adverse pregnancy events. However, ureteral stent placement was associated with a lower incidence of hospital admissions, emergency department visits, exchange procedures, and new UTIs or pyelonephritis.

Management of urolithiasis in pregnancy

Urolithiasis is the most common cause of nonobstetric abdominal pain, resulting in 1.7 admissions per 1000 deliveries. Urolithiasis most commonly occurs in the second and third trimesters, with an incidence between 1:125 and 1:2000. Acute urinary system obstructions are challenging to manage in obstetric patients because they contribute to physiological and anatomical changes that result in pathological outcomes. The restricted use of computed tomography in diagnosing and managing urolithiasis is particularly challenging. In addition, a prompt diagnosis is required because the presence of renal calculi during pregnancy increases the risk of fulminating sepsis and preterm delivery. Affected pregnancies are conservatively managed; however, 1 in 4 requires surgical intervention. Indications for surgical interventions are complex and range from nephrostomy insertion to empirical stent placement or ureteroscopy. Therefore, a multidisciplinary approach is required to optimize patient care. The diagnosis and management of urolithiasis in pregnancy are complex. We reviewed the role, safety, advantages and disadvantages of diagnostic tests and treatment used to manage acute urinary obstructions in pregnancy.

Management of urolithiasis in pregnancy: A systematic review and meta-analysis

PURPOSE

Management of nephrolithiasis is unique in pregnancy and requires multidisciplinary care. To identify the effectiveness or safety of temporary drainage or definitive treatment methods to manage urolithiasis in pregnancy.

METHODS

The search strategy aimed to find both published and unpublished studies was conducted in August 2021. Studies published in any language on any date were considered for inclusion.

RESULTS

Of a total of 3349 publications, 36 studies were included in our qualitative evaluation and 32 studies in the quantitative synthesis. The commonly reported method was stent insertion (n = 29 studies), pneumatic (n = 12), laser (n = 9) lithotripsy, and stone removal using any devices (basket, grasper, or forceps) (n = 11). In seven studies, the authors reported the outcomes of conservative management, and the results showed that the stone-free rate is 54%, and symptom relief occurred in 62% of women. Seven eligible studies reported that 79.9% of urolithiasis were expulsed through stent insertion, while this rate was 94.6% among percutaneous nephrostomy use in two included studies, 88.5% for pneumatic lithotripsy (n = 7 studies), and 76.4% for laser lithotripsy (n = 4 studies), or 95.4% for stone removal method. In addition, adverse events were reported in less than 10% of pregnant women.

CONCLUSIONS

The results showed that stent, pneumatic or laser lithotripsy, and ureteroscopic stone removal were the commonest used methods in the included studies. They can be effective and safe treatment approaches without major maternal or neonatal complications, and could be introduced as an effective and safe therapeutic method for urolithiasis during pregnancy. However, most of the included studies had moderate quality according to critical appraisal checklists. Further prospective studies are needed to reach a conclusion.

Pregnancy Outcomes in a Cohort of Patients Who Underwent Double-J Ureteric Stenting-A Single Center Experience

Background and Objectives: Minimally invasive procedures, such as double-J ureteric stenting, could be a promising therapeutic alternative to conservative management of obstructive urinary tract pathology. We aimed to evaluate the safety and effectiveness of double-J ureteric stenting in pregnant women with ureterohydronephrosis or urolithiasis, along with their infectious complications, and to assess the pregnancy outcomes of this cohort of patients in comparison with a control group. Materials and Methods: This observational retrospective study included 52 pregnant patients who underwent double-J ureteric stenting for urologic disorders in the Urology Department of ‘C.I. Parhon’ University Hospital, and who were followed up at a tertiary maternity hospital- ‘Cuza-Voda’, Iasi, Romania. The control group (63 patients) was randomly selected from the patient’s cohort who gave birth in the same time frame at the maternity hospital, without urinary pathology. Clinical, sonographic, and laboratory variables were examined. Descriptive statistics, non-parametric tests, and a one-to-one propensity score-matched analysis were used to analyze our data. Results: The univariate analysis indicated a significant statistical difference between the control group and the interventional group regarding maternal age (p = 0.018), previous maternal history of renal colic (p = 0.005) or nephrolithiasis (p = 0.002). After applying the propensity score-matched analysis, cesarean delivery rates (p < 0.001), preterm labour (p = 0.039), premature rupture of membranes (p = 0.026), preterm birth rates (p = 0.002), and post-partum UTI rates (p = 0.012) were significantly different between the control group and the matched treatment group. Ureterohydronephrosis, whether simple (n = 37; 71.2%) or infected (n = 13; 25%), was the main indication for double-J ureteric stenting. Complications such as pain (n = 21; 40.3%), stent migration (n = 3; 5.76%) or encrustation (n = 2; 3.84%), as well as reflux pyelonephritis (n = 2; 3.84%) and gross hematuria (n = 1; 1.92%) were recorded during follow-up. Conclusions: Our results show that double-J stenting is a safe and effective treatment option for pregnant patients with obstructive urological disorders.

MRI in Pregnancy and Precision Medicine: A Review from Literature

Magnetic resonance imaging (MRI) offers excellent spatial and contrast resolution for evaluating a wide variety of pathologies, without exposing patients to ionizing radiations. Additionally, MRI offers reproducible diagnostic imaging results that are not operator-dependent, a major advantage over ultrasound. MRI is commonly used in pregnant women to evaluate, most frequently, acute abdominal and pelvic pain or placental abnormalities, as well as neurological or fetal abnormalities, infections, or neoplasms. However, to date, our knowledge about MRI safety during pregnancy, especially about the administration of gadolinium-based contrast agents, which are able to cross the placental barrier, is still limited, raising concerns about possible negative effects on both the mother and the health of the fetus. Contrast agents that are unable to cross the placenta in a way that is safe for the fetus are desirable. In recent years, some preclinical studies, carried out in rodent models, have evaluated the role of long circulating liposomal nanoparticle-based blood-pool gadolinium contrast agents that do not penetrate the placental barrier due to their size and therefore do not expose the fetus to the contrast agent during pregnancy, preserving it from any hypothetical risks. Hence, we performed a literature review focusing on contrast and non-contrast MRI use during pregnancy.

Safety and efficacy of flexible and semi-rigid ureteroscopy with laser lithotripsy for the management of ureteral calculi in pregnancy

Background

Symptomatic ureteric stone during pregnancy can present a clinical challenge because of potential risks to both the mother and foetus. Ureteroscopy with laser and stone basket extraction represents an emerging strategy for definitive stone management in pregnancy, with minor complications. We aimed to evaluate the safety and efficacy of ureteroscopy with auxiliary procedures as a primary treatment for pregnant women with symptomatic ureteric stones who have failed conservative management.

Methods

A prospective analysis was conducted in the Urology Department of Sulaymaniyah Teaching Hospital from June 2017 to November 2019 to evaluate pregnant patients who were treated with ureteroscopy and holmium laser lithotripsy for symptomatic ureteric stone.

Results

Twenty-six pregnant women aged between 18 and 34 years presented with renal colic (22 patients, 84.61%), severe hydronephrosis (3 patients, 11.53%), and progressive hydronephrosis (1 patient, 3.8%), suggesting ureteric stones. The diagnosis was established by abdominal ultrasonography. The mean stone size was 7.38 mm, ranging from 6–12 mm. The stones were located in the proximal ureter (n = 6, 23.1%), middle ureter (n = 0), and distal ureter (n = 20, 76.9%). Complete stone fragmentation was achieved in all patients. The overall procedure success rate was 87%, the stone-free rate was 23 out of 26 cases (88.46%), and no major obstetric or urologic complications were encountered.

Conclusions

Ureteric stone in pregnancy requires a high index of suspicion for a prompt and correct diagnosis. Ureteroscopy: flexible or semirigid endoscopy combined with holmium: YAG laser lithotripsy or with stone extraction are a preferred modality for the definitive treatment of symptomatic ureteric stone in pregnancy.

Risk factors of uterine contraction after ureteroscopy in pregnant women with renal colic

Background

Ureteroscopy is widely applied in pregnant women with renal colic, but such patients are easy to experience uterine contraction after surgery. There are many factors which may affect uterine contraction, this study aims to explore the risk factors of uterine contraction triggered by ureteroscopy in pregnant women with renal colic.

Methods

One hundred and one pregnant women were retrospectively analyzed, the patients were hospitalized because of severe renal colic. All patients received ureteroscopy during which double J catheters were inserted into ureters for drainage. Patients received other medical treatments individually according to their condition and uterine contractions were detected by EHG within 12 h after operation. Patients were classified as group A (uterine contraction) and group B (no uterine contraction) according to the presence or absence of continuously regular uterine contraction. Clinical characteristics were collected for further analysis, including history of childbirth, anesthesia method, application of phloroglucinol or not, operation time, Oxygen inhalation or not, pain relief or not after surgery, systemic inflammatory response syndrome (SIRS) occurred or not. A binary logistic regression analysis model was established to explore whether such clinical characteristics were relevant to uterine contraction after ureteroscopy.

Results

Continuously regular uterine contraction presented in 46 pregnant women within 12 h after ureteroscopy, making the incidence of uterine contraction as high as 45.54%. The presence of uterine contraction was related to the following factors(P < 0.05): history of childbirth (primipara versus multipara)(OR 6.593, 95% CI 2.231–19.490), operation time (each quarter additional) (OR 2.385, 95% CI 1.342–4.238), application of phloroglucinol (yes versus not) (OR 6.959, 95% CI 1.416–34.194), pain relief after surgery(yes versus not)(OR 6.707, 95% CI 1.978–22.738), SIRS occurred after surgery (yes versus not) (OR 0.099, 95% CI 0.014–0.713).

Conclusion

Continuously regular uterine contraction is easy to occur within 12 h after ureteroscopy in pregnant women. SIRS occurred after surgery is a risk factor for uterine contraction; on the contrary, no history of childbirth, shorter operation time, application of phloroglucinol, pain relief after surgery are protective factors.

Catastrophic complications of urolithiasis in pregnancy

Urolithiasis is the most common non-obstetric complication in pregnancy and has the potential to cause grave consequences resulting in pregnancy loss. We present two such cases. First, a 24-year-old woman, 5 weeks pregnant with a history of urolithiasis presented with right flank pain and fever. She was found to have a right perinephric collection and during the course of her treatment suffered an abortion. The second case was a 25-year-old woman who presented in septic shock. She underwent emergency lower segment caesarean section elsewhere 10 days ago for intrauterine death at 38 weeks of gestation. On evaluation, she was found to have bilateral stone disease with a left subcapsular haematoma. Both the cases were managed conservatively and are planned for definitive management. Thus, women of childbearing age with diagnosed urolithiasis should get themselves evaluated and be free of stone disease before planning a family to prevent increased obstetric complications during pregnancy.

Ultrasound Diagnosis and Active Ureteroscopy for Obstructive Ureteral Calculi during Pregnancy: Multicenter Experience

Objectives: To evaluate the safety and efficacy of ultrasound (US) and primary ureteroscopy (URS) in the management of symptomatic obstructive ureteric stones during pregnancy. Patients and Methods: A prospective multicenter study was performed between June 2013 and December 2019, including all consecutive pregnant patients admitted to three urology centers with intractable renal colic with obstructed ureter secondary to obstructive ureteral calculi. Color Doppler ultrasound was used to evaluate renal Resistive Index (RI) and ureter jet. Primary URS was performed to remove the blocking stones. The safety and effectiveness of the procedures were assessed, as well as the stone-free rate (SFR) and the condition of the upper tract after delivery. Results: A total of 111 pregnant patients were included with a mean age of 27.4 ± 4.4 years and a mean renal RI of 0.78 ± 0.02. US diagnosed stones in 46.8% of patients, while 100 (90%) patients had altered lower ureter urinary jet, including 86.5% who had URS-confirmed ureteric stones; SFR was 95.8% with no serious urologic, fetal, or obstetric complications. Nine percent of patients had premature delivery, which was significantly correlated with postoperative urinary tract infection and premature uterine contraction (p ˂ 0.0001). In the third-month follow-up of US, all patients showed no residual hydronephrosis. Postoperative follow-up procedures were required in 15.3% of patients. Conclusion: Obstructive ureteral stones during pregnancy can be detected safely and appropriately with a combined elevated renal RI and absent ureteral jet detected by Doppler US. Definitive URS is an efficient and safe alternative option for those who fail in conservative management.

Management of ureteric stone in pregnancy: a review

Background

Urolithiasis in pregnancy is a major health concern and is one of the most common causes for non-obstetrical abdominal pain and subsequent hospital admission during pregnancy. The incidence of urinary calculi during pregnancy varies in the range of 1/200 to 1/2000. Acute ureteric colic in pregnancy is associated with significant potential risks to both mother and fetus. Significant anatomic and functional changes occur in pregnancy which not only lead to stone formation but also create diagnostic dilemma. The diagnosis of ureteric calculi can be incorrect in about 28% of pregnant patients.

Main body

Management of ureteric stone during pregnancy is remaining to be a challenge for the treating urologist. Because of the inability to use good imaging options for the diagnosis confirmation and more invasive approach for the treatment, management continues to be difficult. The main threats are preterm labor with delivery and premature rupture of membranes. Other pregnancy complications are obstructive uropathy, gestational diabetes mellitus, recurrent abortions and pre-eclampsia. Management of diagnosed ureteric stone is unique in the pregnant population and requires multi-disciplinary care. It should be individualized for each patient and moves preferably from conservative to invasive approaches sequentially. With continued advancements in endourological techniques, few definitive treatment options are also available for such patients.

Conclusion

There are several lacunae related with the diagnostic imaging, medical expulsive therapy, reliability of ureteral stent/percutaneous nephrostomy insertions and safety of ureteroscopy during pregnancy. Herein, we review the management of ureteric stone during pregnancy, the various diagnostic modalities and treatment options with their advantages and disadvantages. We also proposed our management algorithm to deal with such clinical scenario in this particular population.

A ten-year, single institution experience with percutaneous nephrostomy during pregnancy

PURPOSE

To evaluate the safety and efficacy of percutaneous nephrostomy (PCN) in pregnancy.

MATERIALS AND METHODS

PCN tubes were placed during 52 pregnancies in 49 patients from 2008 to 2018. The medical records during pregnancies were retrospectively reviewed for imaging findings, procedural parameters, outcomes of delivery, and complications.

RESULTS

The mean gestational age on percutaneous nephrostomy placement was 27 weeks (range, 8-36 weeks). PCN catheters were placed for the following indications: 1) flank or lower abdominal pain (42%), 2) obstructing calculi (37%), 3) pyelonephritis (20%), and 4) obstructing endometrioma (2%). Prior to PCN, retrograde ureteric stenting was performed in 17 of 49 patients (34%) and attempted but failed in 4 patients (8%). Nephrostomy drainage relieved pain completely or significantly in all 12 patients without prior ureteral stenting, but in only 4 of 10 with retrograde ureteric stents. In one patient in whom the ureteral stent had been removed, PCN relieved her flank pain. The mean number of PCN catheter exchanges was 1.6, ranging from 0 to 9, with a mean time interval of 21.3 days between exchanges. There were 29 difficult exchanges due to encrustation in 15 patients with a mean of 20.5 days between exchanges.

CONCLUSIONS

PCN drainage is a safe and effective treatment for managing symptomatic hydronephrosis in pregnant patients but is less effective in treating pain when retrograde ureteral stents are in place. Rapid encrustation, seen more commonly in pregnancy, tends to recur in the same patients and requires more frequent exchanges than the general population.

Urological issues in pregnancy: A review for urologists

Urological issues in the pregnant patient present a unique clinical dilemma. These patients may be challenging to treat due to risks associated with medications and surgical procedures. This review aims to provide an update on the physiological changes and surgical risks in pregnancy. In addition, we review the approach for management of urolithiasis and urinary tract infections in pregnancy. Lastly, we highlight the importance of a multidisciplinary approach to placenta percreta, a condition not commonly addressed in urological education.

Nephrolithiasis in Pregnancy: Treating for Two

OBJECTIVES

To review the literature regarding the epidemiology of stone disease and develop a management algorithm based on current evidence and societal guidelines.

METHODS

A structured literature review was performed to determine highest quality of evidence guiding care for pregnant patients with symptomatic nephrolithiasis. PUBMED and EMBASE databases were searched using terms "pregnancy," "nephrolithiasis," or "pregnancy" and "renal colic" alone and in combination with "stone", "kidney stone," "ultrasound," "MRI," "CT," "percutaneous nephrostomy," "ureteral stent," or "ureteroscopy." All English-language abstracts were reviewed for relevance and full-length articles were reviewed for content. Articles published prior to 1990 were excluded, and priority for inclusion was given to multi-institutional studies and larger institutional studies, reflecting the highest level of current available evidence and most contemporaneous practice patterns.

RESULTS

Symptomatic nephrolithiasis affects less than 1% of pregnancies but poses unique diagnostic challenges due to the physiologic changes of pregnancy and risks of ionizing radiation exposure to the fetus. Ultrasound remains the imaging modality of choice. Most patients may be managed non-operatively, but drainage with percutaneous nephrostomy or ureteral stent may be performed if warranted. Growing evidence also supports the safety and efficacy of definitive stone treatment.

CONCLUSIONS

Though rare, symptomatic nephrolithiasis poses significant clinical challenges due to the need to minimize risk for both mother and fetus with diagnostic and therapeutic interventions. A multi-disciplinary approach is paramount, as is shared decision making with the patient at each step of care.

Detection of distal ureteral stones in pregnancy using transvaginal ultrasound

AIMS

To determine the performance of transvaginal ultrasound for the visualization of distal ureteral stones in pregnant patients with renal colic and to evaluate the diagnostic value of secondary findings suggestive of obstructing ureteral stone disease.

METHODS

We retrospectively identified 129 pregnant patients with a total of 142 encounters with both abdominal and transvaginal ultrasound. Ultrasound images for each patient were reviewed recording the presence of stone with location, hydronephrosis, resistive indices (RI), and status of the ureteral jets. Patients were subcategorized into two groups based on the visualization of distal ureteral stone.

RESULTS

The transvaginal technique identified 94% (N = 16/17) of sonographically detected stones in the distal ureter/urethra, while the transabdominal technique identified 29% (N = 5/17). The combined imaging for initial assessment of renal colic in pregnancy demonstrated a sensitivity of 89%, specificity 100%, and negative predictive value (NPV) of 98%. The frequency of hydronephrosis was statistically greater in the visualized stone group (94% vs 51%). Mean RI was identical in both groups however the delta RI was significantly elevated in those patients with distal ureteral stones with a mean delta RI value of 0.05. The rate of absence of ureteral jets was not statistically significant.

CONCLUSION

The present data would suggest a utility of transvaginal ultrasound for the evaluation of the pregnant patient with 94% of distal stones being detected transvaginal versus 29% transabdominally. Additionally, there was significantly increased hydronephrosis and elevated RIs in patients with distal ureteral stones.

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.

MRI in pregnancy: Indications and practical considerations

There is a constantly evolving knowledgebase regarding the safety of MRI in pregnant patients, as well as the safety of gadolinium administration, given potential fetal risks. This review provides an overview of national and international recommendations for patient screening and safety by trimester, evaluates the most recent literature regarding administration of gadolinium in pregnant patients, and discusses technical requirements when imaging pregnant patients. A protocol for imaging pregnant patients is provided, and multiple common indications for MRI in pregnancy are discussed. Level of Evidence 5. Technical Efficacy Stage 5. J. Magn. Reson. Imaging 2019;49:621-631.

Contemporary best practice urolithiasis in pregnancy

Urolithiasis is the most common nonobstetric complication in the gravid patient. The experience can provoke undue stress for the mother, fetus, and management team. The physiologic changes of pregnancy render the physical exam and imaging studies less reliable than in the typical patient. Diagnosis is further complicated by the need for careful selection of imaging modality in order to maximize diagnostic utility and minimize obstetric risk to the mother and ionizing radiation exposure to the fetus. Ultrasound remains the first-line diagnostic imaging modality in this group, but other options are available if results are inconclusive. A trial of conservative management is uniformly recommended. In patients who fail spontaneous stone passage, treatment may be temporizing or definitive. While temporizing treatments have classically been deemed the gold standard, ureteroscopic stone removal is now acknowledged as a safe and highly effective definitive treatment approach. Ultimately, a multidisciplinary, team-based approach involving the patient, her obstetrician, urologist, radiologist, and anesthesiologist is needed to devise a maximally beneficial management plan.

Urolithiasis in pregnancy

Clinicians are faced with multiple diagnostic and treatment challenges when managing pregnant women with urolithiasis. Anatomical and physiological changes during pregnancy have to be taken into account whilst simultaneously considering both the expectant mother and the foetus. Ultrasonography remains the first-choice imaging modality, notwithstanding its potentially poor diagnostic accuracy. There is currently no consensus on second-line investigation for suspected urolithiasis. Low-dose non-contrast CT is highly sensitive, but the long-term effects of ionizing radiation on the foetus remain unknown. As far as treatment is concerned, expectant therapy is the primary option for management in the majority of cases. Percutaneous nephrostomy or ureteric stent placements are safe temporizing measures in relieving an acutely obstructed system and should be expedited in the presence of sepsis. Studies have shown ureteroscopy to be safe and effective during pregnancy with no significant risk to the foetus. It is important for the clinician to explain clearly the risks associated with the investigation and management options to the pregnant patient, including an acknowledgement that some of these remain unquantified, or even unknown.

Ureteral Stent Insertion in the Management of Renal Colic during Pregnancy

To determine an optimal invasive intervention for renal colic patients during pregnancy after conservative treatments have been found to be unhelpful. Among the available invasive interventions, we investigated the reliability of a ureteral stent insertion, which is considered the least invasive intervention during pregnancy. Between June 2006 and February 2015, a total of 826 pregnant patients came to the emergency room or urology outpatient department, and 39 of these patients had renal colic. The mean patient age was 30.49 years. In this retrospective cohort study, the charts of the patients were reviewed to collect data that included age, symptoms, the lateralities and locations of urolithiasis, trimester, pain following treatment and pregnancy complications. Based on ultrasonography diagnoses, 13 patients had urolithiasis, and 13 patients had hydronephrosis without definite echogenicity of the ureteral calculi. Conservative treatments were successful in 25 patients. Among these treatments, antibiotics were used in 15 patients, and the remaining patients received only hydration and analgesics without antibiotics. Several urological interventions were required in 14 patients. The most common intervention was ureteral stent insertion, which was performed in 13 patients to treat hydronephrosis or urolithiasis. The patients' pain was relieved following these interventions. Only one patient received percutaneous nephrostomy due to pyonephrosis. No pregnancy complications were noted. Ureteral stent insertion is regarded as a reliable and stable first-line urological intervention for pregnant patients with renal colic following conservative treatments. Ureteral stent insertion has been found to be equally effective and safe as percutaneous nephrostomy, which is associated with complications that include bleeding and dislocation, and the inconvenience of using external drainage system.

Magnetic Resonance Imaging of Abdominal and Pelvic Pain in the Pregnant Patient

The utility of MR imaging in evaluating abdominal and pelvic pain in the pregnant patient is discussed. Details regarding the indications, technical aspects, and imaging findings of various common abdominal and pelvic abnormalities in pregnancy are reviewed.

The internist and the renal resistive index: truths and doubts

The renal resistive index (RRI) is measured by Doppler sonography in an intrarenal artery, and is the difference between the peak systolic and end-diastolic blood velocities divided by the peak systolic velocity. The RRI is used for the study of vascular and renal parenchymal renal abnormalities, but growing evidence indicates that it is also a dynamic marker of systemic vascular properties. Renal vascular resistance is only one of several renal (vascular compliance, interstitial and venous pressure), and extrarenal (heart rate, aortic stiffness, pulse pressure) determinants that combine to determine the RRI values, and not the most important one. RRI cannot always be considered a specific marker of renal disease. To summarize from the literature: (1) hydronephrosis, abdominal hypertension, renal vein thrombosis and acute kidney injury are all associated with an acute increase in interstitial and venous pressure that determine RRI values. In all these conditions, RRI is a reliable marker of the severity of renal damage. (2) The hemodynamic impact of renal artery stenosis can be assayed by the RRI decrease in the homolateral kidney by virtue of decreasing pulse pressure. However, renal diseases that often coexist, increase renal vascular stiffness and hide the hemodynamic effect of renal stenosis. (3) In transplant kidney and in chronic renal disease, high RRI values (>0.80) can independently predict renal and clinical outcomes, but systemic (pulse pressure) rather than renal hemodynamic determinants sustain the predictive role of RRI. (4) Higher RRI detects target renal organ damage in hypertension and diabetes when renal function is still preserved, as a marker of systemic atherosclerotic burden. Is this the fact? We attempt to answer.

Minimally invasive surgical treatment for kidney stone disease

Minimally invasive interventions for stone disease in the United States are mainly founded on 3 surgical procedures: extracorporeal shock wave lithotripsy, ureteroscopic lithotripsy, and percutaneous nephrolithotomy. With the advancement of technology, treatment has shifted toward less invasive strategies and away from open or laparoscopic surgery. The treatment chosen for a patient with stones is based on the stone and patient characteristics. Each of the minimally invasive techniques uses an imaging source, either fluoroscopy or ultrasound, to localize the stone and an energy source to fragment the stone. Extracorporeal shock wave lithotripsy uses a shock wave energy source generated outside the body to fragment the stone. In contrast, with ureteroscopy, laser energy is placed directly on the stone using a ureteroscope that visualizes the stone. Percutaneous nephrolithotomy requires dilation of a tract through the back into the renal pelvis so that instruments can be inserted directly onto the stone to fragment or pulverize it. The success of the surgical intervention relies on performing the least invasive technique with the highest success of stone removal.

Anesthetic exposure in the treatment of symptomatic urinary calculi in pregnant women

OBJECTIVE

To assess the duration and total number of anesthetic exposures required for the treatment of urolithiasis during pregnancy, specifically comparing temporizing measures with active treatment because urolithiasis and its management may pose potential theoretical risks for the mother and fetus.

MATERIALS AND METHODS

We retrospectively reviewed patients with a confirmed diagnosis of urolithiasis during pregnancy who underwent surgical intervention from 1997 to 2012 at our institution. The number and duration of anesthetic exposures were assessed.

RESULTS

We identified 26 women with urolithiasis during pregnancy, of which 15 (58%) were treated with temporizing stents and 11 (42%) with ureteroscopic stone extraction. In the ureteroscopy group, the median number of anesthetic exposures was 1.18 (interquartile range [IQR], 1-2), and the median total anesthetic time was 80 minutes (IQR, 37-126 minutes). In the stent group, 6 (40%) required multiple stent exchanges for a median of 1.47 (IQR, 1-3) anesthetic events and a median total anesthetic time of 70 minutes (IQR, 29-208 minutes). In the ureteral stent group, 7 women (47%) were induced before spontaneous labor due to inability to tolerate the stent. There was no difference in the number of anesthetic events (P = .208) or anesthesia time (P = .503) between stenting and ureteroscopy.

CONCLUSION

Women undergoing ureteroscopic surgical intervention during pregnancy were at no greater risk in the number or cumulative duration of anesthesia exposure than women managed with temporizing ureteral stent placement and subsequent exchanges.

Invasive management of proximal ureteral calculi during pregnancy

OBJECTIVE

To review our experience with invasive management of proximal ureteral calculi during pregnancy when conservative treatment fails.

METHODS

From February 2006 to September 2012, a total of 87 pregnant women received invasive management for proximal ureteral calculi in our center. Invasive management included the following: double-J stent insertion, percutaneous nephrostomy (PCN), and ureteroscopic lithotripsy (URSL). The medical records of these patients were reviewed retrospectively.

RESULTS

Of the 87 patients, 4 patients received PCN; 19 patients received cystoscopic double-J stent insertion, whereas 2 patients (10.5%) failed in guide wire inserting and switched to ureteroscopic aid; a total of 64 patients received URSL with holmium laser, in which 52 patients (81.2%) had complete fragmentation of calculi; in 9 patients (14.1%), stone fragments retrograde migrated to the renal pelvis; in 3 patients (4.7%), the stone could not be reached because of serious ureteral tortuosity. One patient (1.6%) patient had a threatened abortion, but this problem was resolved immediately using conservative treatment. All patients completed the full term of pregnancy, and no serious obstetric or urologic complications were observed.

CONCLUSION

For pregnant patients with proximal ureteral calculi, double-J stent insertion, PCN, and URSL all are effective and safe options when conservative treatment fails. They should be chosen on the basis of different patient's condition. However, patient's postoperative tolerance was poor for double-J stent insertion and PCN; URSL (especially with holmium laser lithotripsy) is more effective and should be considered as the preferred choice.

[Renal colic in pregnancy: series of 103 cases]

PURPOSE

To evaluate the management of renal colic in pregnant woman in our hospital.

MATERIAL AND METHODS

A retrospective study of 103 pregnant patients, hospitalized for back pain of renal colic type, associated or not with a urinary tract infection, between January 2005 and October 2010. Three groups of patients were identified from the initial clinical and paraclinical (ultrasound). Group I involved patients with dilatation of the renal cavities associated with septic syndrome, they received analgesic treatment and empiric antibiotic therapy. Group II involved patients with dilatation of the renal cavities isolated, without fever, they received only analgesic treatment. Group III involved patients without dilatation of the renal cavities, they received analgesic treatment and antibiotics in case of fever, and then another cause of pain was sought.

RESULTS

The renal colic was due to a stone in 19.4 % of cases. A urinary infection was associated in 28 % of patients. Ultrasond was sufficient to confirm the diagnosis in 96 % of cases. In 4 % of cases, MRI or low-dose CT were necessary. Therapeutic management based on analgesic treatment, associated with probabilistic antibiotherapy or adapted in case of documented infection, allowed sedation of pain in two-third of cases. In case of failure or signs of severity, the urinary diversion by a double J stent was efficient, without consequences on pregnancy issue. One stone was treated by ureteroscopy during pregnancy without complication.

CONCLUSION

The management of renal colic in pregnant woman based on ultrasound diagnosis, symptomatic treatment and urinary diversion by double J stent in case of failure therefore seemed quite sure on mother and fetus.

The evaluation of ureteroscopy and pneumatic lithotripsy results in pregnant women with urethral calculi

Background

Urinary stone incidence in pregnancy has been reported in a wide range, from 1 in 200 to 1 in 2000 cases.

Objectives

The aim of this study was to investigate the efficacy and safety of ureteroscopic treatment and its results and complications for pregnant women with urinary stones.

Patients and Methods

From 2003 till 2011, 113 pregnant patients with symptomatic urolithiasis were admitted to the urology emergency clinic at Imam Reza hospital. All patients were initially treated conservatively, resulting in spontaneous passage of the calculi in 69 patients. Forty-four patients with symptomatic urolithiasis were included in the study. Post-operative follow ups, including maternal and fetal health was performed by a gynecologist consult fetal heart rate assessment and urine analysis and culture and renal and urethral ultrasonography.

Results

The mean age of the patients was 23 years ± 2 (19-34) and the mean gestational age was 24 ± 3 weeks. The overall and pneumatic lithotripsy success rate was 100%. All patients from the interventional group delivered at term with no fetal or maternal complications. There was no morbidity during and after the operation.

Conclusions

In conditions, medical management of urinary stones and consequent renal colic in pregnant women cannot improve patients’ symptoms, choosing of a surgical method like setting of a DJ catheter or URS and pneumatic lithotripsy can be a safe and effective way for the health of both the mother and fetus. Of course, more research is needed to establish this approach as the standard method in pregnancy urinary stones.

Double-J ureteric stenting in pregnancy: A single-centre experience from Iraq

OBJECTIVES

To evaluate the safety and effectiveness of ureteric stenting with a JJ stent in pregnant women, to relieve renal obstruction and intractable flank pain.

PATIENTS AND METHODS

All pregnant patients presenting with intractable flank pain, with or without complications, to a tertiary national teaching hospital in Kurdistan/Iraq, and necessitating ureteric stenting with a JJ stent, were prospectively assessed for this study between March 2008 and March 2010.

RESULTS

In all, 30 pregnant patients presented with intractable flank pain necessitating JJ ureteric stenting during the 25 months. Intractable flank pain (23 patients, 77%) was the most common indication for ureteric stenting, followed by flank pain with clinical sepsis (six, 20%). All pregnant women had hydronephrosis on ultrasonography (US), and 12 (40%) had evidence of coexisting renal stones on US. All ureteric stents were inserted successfully. The mean (range) indwelling time was 47.4 (3-224) days. Radiologically, 14 (47%) and 15 (50%) had complete resolution of the hydronephrosis on follow-up US in late pregnancy and in the early postnatal period, respectively. Two-thirds of patients had a clinical improvement immediately (15, 50%) and soon after (five, 17%) surgery. Stent encrustation (three, 10%), stent migration (three, 10%) and stent irritation (five, 17%) were reported as complications. The post-natal evaluation confirmed that half the patients had urinary calculus disease.

CONCLUSION

Ureteric stenting during pregnancy can be safe, with no intraoperative imaging and even under local anaesthesia. It provides good symptom relief and has a low complication rate. We therefore advocate it as a first-line treatment in pregnant women with therapy-resistant flank pain.

Excessive urinary tract dilatation and proteinuria in pregnancy: a common and overlooked association?

BACKGROUND

Proteinuria and dilatation of the urinary tract are both relatively common in pregnancy, the latter with a spectrum of symptoms, from none to severe pain and infection. Proteinuria is a rare occurrence in acute obstructive nephropathy; it has been reported in pregnancy, where it may pose a challenging differential diagnosis with pre-eclampsia.The aim of the present study is to report on the incidence of proteinuria (≥ 0.3; ≥ 0.5 g/day) in association with symptomatic-severe urinary tract dilatation in pregnancy.

METHODS

Case series.

SETTING

Nephrological-Obstetric Unit dedicated to pregnancy and kidney diseases (January 2000-April 2011).

SOURCE

database prospectively updated since the start of the Unit. Retrospective review of clinical charts identified as relevant on the database, by a nephrologist and an obstetrician.

RESULTS

From January 2000 to April 2011, 262 pregnancies were referred. Urinary tract dilatation with or without infection was the main cause of referral in 26 cases (predominantly monolateral in 19 cases): 23 singletons, 1 lost to follow-up, 1 twin and 1 triplet. Patients were referred for urinary tract infection (15 cases) and/or renal pain (10 cases); 6 patients were treated by urologic interventions ("JJ" stenting). Among them, 11 singletons and 1 triple pregnancy developed proteinuria ≥ 0.3 g/day (46.1%). Proteinuria was ≥ 0.5 g/day in 6 singletons (23.1%). Proteinuria resolved after delivery in all cases. No patient developed hypertension; in none was an alternative cause of proteinuria evident. No significant demographic difference was observed in patients with renal dilatation who developed proteinuria versus those who did not. An association with the presence of "JJ" stenting was present (5/6 cases with proteinuria ≥ 0.5 g/day), which may reflect both severer obstruction and a role for vescico-ureteral reflux, induced by the stent.

CONCLUSIONS

Symptomatic urinary tract dilatation may be associated with proteinuria in pregnancy. This association should be kept in mind in the differential diagnosis with other causes of proteinuria in pregnancy, including pre-eclampsia.

[Radiology and pregnancy : Part 2: clinical recommendations]

In spite of a growing number of radiological scans in pregnant women there is still a high level of uncertainty concerning radiation exposure to the fetus. At the same time, the risk of fetal radiation injury is frequently overestimated. This entails an avoidable fear in the pregnant patient and may delay urgently required imaging and thus lead to an increased risk for maternal and fetal health. As a consequence, radiological scans in pregnant patients do not only require a thorough medical check but also a careful estimate of the specific radiation exposure to the fetus. The previous first part of the article described the legal requirements in Germany, the technical exposure and pharmacological risks for the pregnant woman and the fetus. The current second article focuses on the risk analysis for examinations with ionizing radiation and will provide recommendations for typical indications for maternal and fetal imaging.

Management of stones in abnormal situations

Stones in abnormal situations present a management conundrum to the urologist. Many of these situations are relatively rare and literature is scanty on the appropriate management. We review the current literature on the management of stones in the setting of pregnancy, calyceal diverticulum, urinary diversions, pelvic kidneys, transplant kidneys, autosomal dominant polycystic kidney disease, horseshoe kidneys, and other renal anomalies. The aims of treatment are complete stone-free status. The modality of treatment should be individualized to the size and location of stone and type of abnormal situation confronted.

Imaging techniques for stone disease and methods for reducing radiation exposure

Imaging plays a critical role in the evaluation of patients with urolithiasis. It is essential for the diagnosis of stones and provides important information to aide in determining the appropriate treatment of renal or ureteral calculi. Imaging for urolithiasis has evolved over the past 30 years. Currently, noncontrast computed tomography remains the first-line imaging modality for the evaluation of patients with suspected urolithiasis. Proper imaging modality selection helps to minimize radiation exposure. Following the principles of As Low As Reasonably Achievable in the operating room can help reduce the amount of radiation patients are exposed to from fluoroscopy.

Clinical effectiveness protocols for imaging in the management of ureteral calculous disease: AUA technology assessment

PURPOSE

This technology assessment addresses the optimal use of imaging in the evaluation and treatment of patients with suspected or documented ureteral stones.

MATERIALS AND METHODS

A comprehensive literature search addressing 4 guiding questions was performed for full text in English articles published between January 1990 and July 2011. The search focused on major subtopics associated with the imaging of ureteral calculi, and included specific imaging modalities used in the diagnosis and management of ureteral calculous disease such as unenhanced (noncontrast) computerized tomography, conventional radiography, ultrasound, excretory urography, magnetic resonance imaging and nuclear medicine studies. Protocols (in the form of decision tree algorithms) were developed based on this literature review and in some instances on panel opinion. The 4 questions addressed were 1) What imaging study should be performed for suspected ureteral calculous disease? 2) What information should be obtained? 3) After diagnosis of a ureteral calculus, what followup imaging should be used? 4) After treatment of a ureteral calculus, what followup imaging studies should be obtained?

RESULTS

Based on these protocols, noncontrast computerized tomography is recommended to establish the diagnosis in most cases, with a low energy protocol advocated if body habitus is favorable. Conventional radiography and ultrasound are endorsed for monitoring the passage of most radiopaque stones as well as for most patients undergoing stone removal. Other studies may be indicated based on imaging findings, and patient, stone and clinical factors.

CONCLUSIONS

The protocols generated assist the clinician in establishing the diagnosis of ureteral calculous disease, monitoring stone passage and following patients after treatment. The protocols take into account not only clinical effectiveness but also cost-effectiveness and risk/harm associated with the various imaging modalities.