Ultrasonographic detection of ureteral jets in normal pregnancy

The course of alterations in ureteral jet dynamics following kidney transplantation: a prospective observational cohort study

OBJECTIVES

To prospectively investigate the alterations and normal ranges of ureteral jet dynamics after double-J-stent (DJS) removal in patients who underwent renal transplantation (RTx).

METHODS

Patients who underwent RTx were prospectively evaluated between November 2017 and June 2018. After RTx, Doppler ultrasonography (D-US) was performed on all patients after DJS removal. Renal artery resistive index (RA-Ri), renal pelvis anterior-posterior diameter (RP-APD), pelvicalyceal system dilation (PCSD), and ureteral jet flow dynamics (maximum and average velocity; JETmax and JETave) were measured by D-US. Also, patients' demographics, estimated glomerular filtration rate (eGFR) levels, and acute rejection were investigated in the study. Patients were assessed two different times by D-US, about 6 and 12 weeks after DJS removal, and the two different measurements were compared with the Wilcoxon test and Chi-square test.

RESULTS

A total of 25 patients were evaluated in the study. Nonobstructive PCSD rate (12% vs 8%), JETave (18.8 vs 12.9 cm/sec), and JETmax (29.2 vs 20 cm/sec) levels were significantly decreased (p values are 0.01, 0.010 and 0.014, respectively). In addition, monophasic and square pattern rates were significantly observed to increase over time (p=0.035); however, ureteral jet patterns were correlated between the two different D-US measurements (R=0.225, p=0.032).

CONCLUSION

After RTx, dilation rate and ureteral jet flow velocities were significantly decreased, and monophasic and square JETpattern rates were significantly increased over time. Ureteral jet dynamics can provide useful information about the follow-up of peristaltic activity in the pelvic-ureteric system.

Utility of trans-vaginal ultrasound in diagnosis and follow-up of non-pregnant sexually active females with lower ureteric calculi

Objective

To assess the utility of trans-vaginal ultrasonography in evaluation of non-pregnant sexually active female patients with lower ureteric calculi.

Methods

A prospective study was done from January 2015 to December 2017 including non-pregnant sexually active females with suspected ureteric calculus. Trans-abdominal ultrasound was initially done in all patients. In those patients in whom trans-abdominal ultrasound was inconclusive or there was indirect evidence of lower ureteric calculus in form of ureteral dilation but no calculus was evident, trans-vaginal ultrasound was done. The patients with ureteric calculi detected on trans-vaginal ultrasound and kept on conservative management were also followed up with trans-vaginal ultrasound. Non-contrast computed tomography was done in patients with inconclusive trans-vaginal ultrasound.

Results

As per the study protocol, 156 out of the total 468 patients evaluated by trans-abdominal ultrasound were eligible for trans-vaginal ultrasound. Trans-vaginal ultrasound was done in 149 patients, as seven patients did not give consent. Seventy-nine patients were detected with a lower ureteric calculus on trans-vaginal ultrasound and 27 patients had gynecologic or other cause for their symptoms. Forty-three patients had an inconclusive trans-vaginal ultrasound of which 36 underwent non-contrast computed tomography, among them only one patient had a lower ureteric calculus. Stone free status could be easily demonstrated on follow-up trans-vaginal ultrasound.

Conclusion

Trans-vaginal ultrasound in addition to trans-abdominal ultrasound is a very useful tool in evaluation of sexually active females with suspected lower ureteric calculus.

Review on diagnosis and management of urolithiasis in pregnancy: an ESUT practical guide for urologists

PURPOSE

Management of urolithiasis in pregnancy can be challenging for most urologists with diagnostic and treatment dilemma to ensure the best outcome for both mother and fetus. We wanted to review the literature for urolithiasis in pregnancy with a practical management guide for urologists.

METHODS

A non-systematic review of literature was carried out for all English language literature using Medline. To ensure a more comprehensive search, the review of diagnosis and management of pregnant patients with urolithiasis was carried out separately, by two authors independently. Due to diagnostic complexity, investigations (US, CT, MRI) carried out were assessed separately.

RESULTS

Our search included diagnostic studies such as US, CT and MRI (73, 20 and 27 articles, respectively) and management studies (55 articles in total). Details on etiology, radiation risk, safety of various diagnostic modalities, medications and treatment options are covered through an evidence-based approach. We provide a practical guide for urologists in what is clearly a stressful situation for patient and physician alike.

CONCLUSIONS

Urolithiasis in pregnancy needs a careful multidisciplinary management to achieve good outcomes for both mother and baby. Our review shows that a balanced approach for diagnosis and treatment seems to achieve the best outcomes in pregnancy.

Epidemiology, pathophysiology, and management of uric acid urolithiasis: A narrative review

An in-depth comprehension of the epidemiology as well as pathophysiology of uric acid urolithiasis is important for the identification, treatment, and prophylaxis of calculi in these patients. Persistently low urinary pH, hyperuricosuria, and low urinary volume are the most important factors in pathogenesis of uric acid urolithiasis. Other various causes of calculus formation comprises of chronic diarrhea, renal hyperuricosuria, insulin resistance, primary gout, extra purine in the diet, neoplastic syndromes, and congenital hyperuricemia. Non-contrast-enhanced computed tomography is the radiologic modality of choice for early assessment of patients with renal colic. Excluding situations where there is acute obstruction, rising blood chemistry, severe infection, or unresolved pain, the initial management ought to be medical dissolution by oral chemolysis since this method has proved to be effective in most of the cases.

An overview of kidney stone imaging techniques

Kidney stone imaging is an important diagnostic tool and initial step in deciding which therapeutic options to use for the management of kidney stones. Guidelines provided by the American College of Radiology, American Urological Association, and European Association of Urology differ regarding the optimal initial imaging modality to use to evaluate patients with suspected obstructive nephrolithiasis. Noncontrast CT of the abdomen and pelvis consistently provides the most accurate diagnosis but also exposes patients to ionizing radiation. Traditionally, ultrasonography has a lower sensitivity and specificity than CT, but does not require use of radiation. However, when these imaging modalities were compared in a randomized controlled trial they were found to have equivalent diagnostic accuracy within the emergency department. Both modalities have advantages and disadvantages. Kidney, ureter, bladder (KUB) plain film radiography is most helpful in evaluating for interval stone growth in patients with known stone disease, and is less useful in the setting of acute stones. MRI provides the possibility of 3D imaging without exposure to radiation, but it is costly and currently stones are difficult to visualize. Further developments are expected to enhance each imaging modality for the evaluation and treatment of kidney stones in the near future. A proposed algorithm for imaging patients with acute stones in light of the current guidelines and a randomized controlled trial could aid clinicians.

EAU Guidelines on Diagnosis and Conservative Management of Urolithiasis

CONTEXT

Low-dose computed tomography (CT) has become the first choice for detection of ureteral calculi. Conservative observational management of renal stones is possible, although the availability of minimally invasive treatment often leads to active treatment. Acute renal colic due to ureteral stone obstruction is an emergency that requires immediate pain management. Medical expulsive therapy (MET) for ureteral stones can support spontaneous passage in the absence of complicating factors. These guidelines summarise current recommendations for imaging, pain management, conservative treatment, and MET for renal and ureteral stones. Oral chemolysis is an option for uric acid stones.

OBJECTIVE

To evaluate the optimal measures for diagnosis and conservative and medical treatment of urolithiasis.

EVIDENCE ACQUISITION

Several databases were searched for studies on imaging, pain management, observation, and MET for urolithiasis, with particular attention to the level of evidence.

EVIDENCE SYNTHESIS

Most patients with urolithiasis present with typical colic symptoms, but stones in the renal calices remain asymptomatic. Routine evaluation includes ultrasound imaging as the first-line modality. In acute disease, low-dose CT is the method of choice. Ureteral stones <6mm can pass spontaneously in well-controlled patients. Sufficient pain management is mandatory in acute renal colic. MET, usually with α-receptor antagonists, facilitates stone passage and reduces the need for analgesia. Contrast imaging is advised for accurate determination of the renal anatomy. Asymptomatic calyceal stones may be observed via active surveillance.

CONCLUSIONS

Diagnosis, observational management, and medical treatment of urinary calculi are routine measures. Diagnosis is rapid using low-dose CT. However, radiation exposure is a limitation. Active treatment might not be necessary, especially for stones in the lower pole. MET is recommended to support spontaneous stone expulsion.

PATIENT SUMMARY

For stones in the lower pole of the kidney, treatment may be postponed if there are no complaints. Pharmacological treatment may promote spontaneous stone passage.

[Infectious diseases and injuries of bladder and urinary tract]

Urinary tract infections are the most common infectious diseases in Germany. In most cases clarification does not rely on imaging techniques other than sonography and is made mostly based on clinical symptoms. Computed tomography (CT) and magnetic resonance imaging (MRI) can be used in selected cases to find the cause and detection or exclusion of complications, e.g. recurrent or atypical and complicated courses. The method of choice for clarification of urolithiasis is CT. Using low-dose techniques, detection or exclusion of urinary stones can be achieved with a high sensitivity and specificity as well as an acceptable level of radiation exposure. Native stone CT supplies additional fundamental information that can substantially influence further therapy planning. The diagnosis of ureteral injuries is clinically and radiologically not trivial and clarification is aided by urographic contrast media. The method of CT cystography has an important role in the diagnostics of urinary bladder injuries.

Renal stones in pregnancy

Diagnosis and treatment of renal stones during pregnancy is a complex problem. Risks to the fetus from ionising radiation and interventional procedures need to be balanced with optimising clinical care for the mother. Management of such patients requires a clear understanding of available options, with a multidisciplinary team approach. In this review, we discuss the role of different diagnostic tests including ultrasound, magnetic resonance urography, and computerized tomography. We also provide an update on recent developments in the treatment of renal stones during pregnancy. Expectant management remains first-line treatment. Where definitive treatment of the stone is required, new evidence suggests that ureteroscopic stone removal may be equally safe, and possibly better than traditional temporising procedures.

[Ureteroscopy: is it the best?]

Over the last 40 years the treatment of urolithiasis passed from open surgical therapies to minimally invasive approaches. From the introduction of the first ureteroscopes in '80s many technological improvements allowed to reduce endourological instruments' size, ensuring in the meanwhile an increasingly high success rate in the resolution of the urolithiasis. The purpose of the study is to review the current role of the ureteroscopy(URS) in the treatment of urinary stones. A non-systematic review was performed considering the most recent Guidelines and results from Literature. The results confirm that, considering ureteral calculi, the stone-free rate (SFR) for URS is significantly higher than for ESWL in the treatment of distal ureteral stones <10 mm and >10 mm. Endoscopy has a first-line role also in the treatment of proximal ureteral stones >10 mm, together with ESWL. Retreatment rate and ancillary procedures are also lower in patients treated with URS, despite it is more invasive if compared with ESWL. Recent data are available in Literature about the treatment of nephrolithiasis with Retrograde Intra-Renal Surgery (RIRS). RIRS is the first-line treatment, together with ESWL, for stones <20 mm, and second choice for stones >20 mm. However, for large renal stones the role of RIRS is still being discussed. In conclusion, the majority of urinary stones can be treated by rigid or flexible URS. Further studies are required to clarify the role of endoscopy in the treatment of large stones, especially if compared to percutaneous approaches.

Incidental genitourinary findings on obstetrics/gynecology ultrasound

Ultrasound is the standard-of-care imaging modality for initial imaging in obstetrics and gynecology. Given the close proximity of the genitourinary system to the uterus and adnexa, it is not surprising that these studies can result in the discovery of incidental genitourinary findings such as ureterocele, ectopic ureter, bladder mass, ureteral stones, cystitis, bladder diverticulum, and pelvic kidney. Recognition of the etiology of these findings is important for appropriate diagnosis and, at times, patient care. Many of these findings are truly incidental and clinically unimportant but other times can be related to the patient's chief complaint.

Management of urinary calculi in pregnancy: a review

Nephrolithiasis during pregnancy can represent a clinical dilemma because of potential risks to both mother and fetus. While the incidence of symptomatic nephrolithiasis during pregnancy varies between 1 in 244 to 1 in 2000 pregnancies, the actual incidence is likely to be higher. A significant proportion of patients with asymptomatic renal calculi are detected incidentally in the nonpregnant population compared with pregnant women. Factors that contribute to the diagnostic challenges include anatomic and physiologic changes to the female urinary tract during pregnancy and the limitations on the use of ionizing radiation. The treatment of such patients requires a multidisciplinary team approach involving the urologist, obstetrician, and radiologist. The potential hazards of intervention (either surgical or medical) and anesthesia need to be considered carefully.

Evaluation of Painful Hydronephrosis in Pregnancy:: Magnetic Resonance Urographic Patterns in Physiological Dilatation Versus Calculous Obstruction

PURPOSE

We evaluated magnetic resonance urography (MRU) appearances in symptomatic hydronephrosis in pregnancy and compared urographic patterns in physiological and calculous disease.

MATERIALS AND METHODS

A total of 24 consecutive pregnant women with symptomatic hydronephrosis underwent MRU, comprising an overview fast T2-weighted examination of the abdomen and pelvis, and thick slab, heavily T2-weighted MRU images, followed by focused, high resolution T2-weighted sequences obtained in an axial and coronal oblique plane through the level of ureteral caliber change.

RESULTS

Of these 24 pregnant women 15 were found to have physiological hydronephrosis, 7 had calculous disease and 2 had preexisting urinary anomalies. MRU findings in physiological hydronephrosis cases were extrinsic compression of the middle third of the ureter, no filling defect and a collapsed ureter below it. Obstruction by ureteral calculi was seen at points of ureteral narrowing in the ureter, that is at the vesicoureteral junction in 2 cases, in the compressed mid ureter in 3 and at the pelviureteral junction in 1. Nonobstructive renal calculi were seen in another patient. Calculi presented throughout pregnancy but physiological hydronephrosis presented only in the late second and third trimesters. With distal calculi the MRU appearance was the double kink sign with constriction at the pelvic brim and the vesicoureteral junction with a standing column of urine in the pelvic ureter. There was renal edema and perirenal extravasation. Small calculi were only identified using high resolution T2-weighted magnetic resonance imaging.

CONCLUSIONS

MRU is a valuable and well tolerated investigation for evaluating painful hydronephrosis in pregnancy. There are characteristic and differing urographic appearances in physiological and calculous obstruction.

Doppler waveform of the ureteric jet in pregnancy

We have shown that the function of the bladder vesicoureteric junction (VUJ) can be studied by the Doppler waveform of the ureteric jet, and this reflects the active sphincteric mechanism of the VUJ. We wished to investigate if the hormonal changes of pregnancy cause any alteration of VUJ function. A total of 107 pregnant women and 375 nonpregnant women were recruited. Three scans, 20 and 32 weeks of gestational age and 3 months postpartum, were done. The occurrence of a monophasic waveform in the nonpregnant group was 1.9%. In the pregnancy group, this was 18.7%, 41.1% and 1.6% at 20, 32 weeks of gestational age and 3 months postpartum, respectively. The difference in occurrence of the monophasic waveforms was statistically significant (both p = 0.0005 at 20 and 32 weeks). This suggests an adverse hormonal effect on the vesicoureteric junction during pregnancy, and may be a factor in the increased risk of UTI in pregnancy.

Colour Doppler evaluation of ureteral jets in normal second and third trimester pregnancy: effect of patient position

The study was designed to investigate the effect of patient position on the detection of ureteral jets in normal pregnancy. The number of jets was recorded for 1 min using colour Doppler ultrasound in 26 healthy asymptomatic gravid women between 16 weeks and 34 weeks gestation. Each patient was examined in the supine position and in both the right and left lateral decubitus positions. Ureteral jets were present on at least one side in 24 patients in the supine position compared with 26 women in the lateral decubitus position. 13 (54%) of the 24 patients in whom jets were seen in the supine position had jets on only one side. A mean of 1.80 jets x min(-1) was detected on the right side and 3.23 jets x min(-1) on the left (p=0.046) in the supine position. In the contralateral decubitus position, jets were detected on the right side in 22 (85%) women and on the left in 25 (96%) women. A mean of 3.07 jets x min(-1) was detected on the right and 4.15 jets x min(-1) on the left. The difference in the frequency of ureteral jets between the supine and lateral decubitus positions was significant (p=0.004 for the right; p=0.011 for the left). However, the difference in the detection rate was significant on only the right side (p=0.016 for the right; p=0.063 for the left). 10 (77%) of 13 patients in whom unilateral absence of ureteral jets was noted had detectable jets in the lateral decubitus position. Our findings demonstrated the utility of the lateral decubitus position in the evaluation of ureters suspicious for obstruction. However, caution is still recommended in diagnosing ureteral obstruction if jets are persistently absent after this manoeuvre.