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Research in Veterinary Science Dec 2022Cats exhibit high susceptibility to urinary organ-related diseases. We investigated the healthy ureter morphologies and compared these with ureters that were surgically...
Cats exhibit high susceptibility to urinary organ-related diseases. We investigated the healthy ureter morphologies and compared these with ureters that were surgically resected distal to a urolithiasis obstruction in cats. Healthy ureters (total length 9.88 ± 0.38 cm) developed adventitia composed of collagen fibers (ADCF), containing a longitudinal muscular layer, toward the distal segment. The healthy ureter was the smallest in the middle segment (4.71-6.90 cm from the urinary bladder) with significantly decreased luminal and submucosal areas compared to those in the proximal segment. Diseased cats exhibited a high incidence of calcium oxalate urolithiasis with renal dysfunction, regardless of age, sex, and body size. Diseased ureters showed increased perimeters, inflammation, and decreased nerves in ADCF. Collagen fibers were increased in the submucosal area, intermuscular spaces, and ADCF, particularly near the obstructed lesion. The mean resected ureter length was 5.66 ± 0.49 cm, suggesting a high obstruction risk in the middle segment. The middle segment also increased the cross-sectional area of the ureter and ADCF, regardless of the distance from the obstructed lesion. The ureters in several cases either lacked the transitional epithelium, or exhibited transitional epithelial hyperplasia, and some of these formed the mucosal folds. In conclusion, we demonstrated the following characteristics and histopathological features of cat ureters: decreases in the ureter size, lumen area, and submucosa area from proximal to middle segment in healthy; ADCF changes in urolithiasis, including increased connective tissues with inflammation and decreased nerves. These data are important to understand the pathogenesis of feline ureteral obstruction.
Topics: Animals; Cat Diseases; Cats; Collagen; Inflammation; Ureter; Ureteral Obstruction; Urolithiasis
PubMed: 35850013
DOI: 10.1016/j.rvsc.2022.06.029 -
Acta Physiologica (Oxford, England) Aug 2022Cyclooxygenase-2 (COX-2) activity protects against oxidative stress and apoptosis early in experimental kidney injury. The present study was designed to test the...
AIM
Cyclooxygenase-2 (COX-2) activity protects against oxidative stress and apoptosis early in experimental kidney injury. The present study was designed to test the hypothesis that COX-2 activity attenuates fibrosis and preserves microvasculature in injured kidney. The murine unilateral ureteral-obstruction (UUO) model of kidney fibrosis was employed and compared with human nephrectomy tissue with and without chronic hydronephrosis.
METHODS
Fibrosis and angiogenic markers were quantified in kidney tissue from wild-type and COX-2 mice subjected to UUO for 7 days and in human kidney tissue. COX-enzymes, prostaglandin (PG) synthases, PG receptors, PGE , and thromboxane were determined in human tissue.
RESULTS
COX-2 immunosignal was observed in interstitial fibroblasts at baseline and after UUO. Fibronectin, collagen I, III, alpha-smooth muscle actin, and fibroblast specific protein-1 mRNAs increased significantly more after UUO in COX-2 vs wild-type mice. In vitro, fibroblasts from COX-2 kidneys showed higher matrix synthesis. Compared to control, human hydronephrotic kidneys showed (i) fibrosis, (ii) no significant changes in COX-2, COX-1, PGE -, and prostacyclin synthases, and prostacyclin and thromboxane receptor mRNAs, (iii) increased mRNA and protein of PGE -EP receptor level but unchanged PGE tissue concentration, and (iv) two- to threefold increased thromboxane synthase mRNA and protein levels, and increased thromboxane B tissue concentration in cortex and outer medulla.
CONCLUSION
COX-2 protects in the early phase against obstruction-induced fibrosis and maintains angiogenic factors. Increased PGE -EP receptor in obstructed human and murine kidneys could contribute to protection.
Topics: Animals; Cyclooxygenase 2; Dinoprostone; Fibrosis; Humans; Kidney; Mice; Prostaglandins E; Prostaglandins I; RNA, Messenger; Receptors, Prostaglandin E, EP2 Subtype; Thromboxanes; Up-Regulation; Ureter; Ureteral Obstruction
PubMed: 35543087
DOI: 10.1111/apha.13828 -
Minerva Urologica E Nefrologica = the... Jun 2018Ureteral obstructions are managed by complex surgery not always feasible for surgical field complexity or poor patient conditions. Various surgical maneuvers, as... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
Ureteral obstructions are managed by complex surgery not always feasible for surgical field complexity or poor patient conditions. Various surgical maneuvers, as ureteral dilation, stenting and percutaneous nephrostomy, can be offered, but they are related to considerable failure rates and negative impact on quality of life. In selected cases, the positioning of long-term expandable metallic ureteral stents (EMUSs) may be an appropriate and successful choice.
EVIDENCE ACQUISITION
Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria, a systematic review of the literature was performed in July 2017 using PubMed, Cochrane Library, Scopus and Web of Science databases. The search was conducted by typing the following terms: "Expandable metallic ureteral stent," "Memokath ureteral stent," "Allium ureteral stent," and "Uventa ureteral stent."
EVIDENCE SYNTHESIS
Twenty studies reported the safety, efficacy and clinical outcomes related to the common available EMUSs. Most studies were single-arm, retrospective and involving a low number of clinical cases, resulting in significant difficulties with outlining indications and drawing conclusions. Available papers showed EMUSs offered a high rate of patency, a long duration and a good quality of life, even if they are associated with significant complications.
CONCLUSIONS
Since the first description of ureteral stents 50 years ago, we have faced a significant evolution in stent design. The current generation of EMUSs offers many advantages, but the onset of adverse effects is still significant and limits their use to selected cases. Further research should be addressed to the realization of prospective, multi-institutional randomized clinical trials to highlight indications to manage appropriately ureteral obstructions.
Topics: Humans; Stents; Ureter; Ureteral Obstruction
PubMed: 29595037
DOI: 10.23736/S0393-2249.18.03035-7 -
Ureteral obstruction and hydronephrosis caused by foreign body: A case report and literature review.Medicine Nov 2019Foreign bodies related ureteral obstruction and hydronephrosis is rare and usually cause numerous problems for clinical physicians. (Review)
Review
RATIONALE
Foreign bodies related ureteral obstruction and hydronephrosis is rare and usually cause numerous problems for clinical physicians.
PATIENT CONCERNS
We report a 36-year-old female who was referred to our hospital due to a 4-year history of dull pain on the left back.
DIAGNOSIS
X-ray and abdominal CT revealed a foreign body around the upper part of the left ureter with ureteral obstruction and hydronephrosis.
INTERVENTIONS
Laparoscopy was performed and a 3-cm sewing needle was removed successfully.
OUTCOMES
After 6 months' follow-up, the patient's ureteral obstruction and hydronephrosis were significantly reduced, and the double-J ureteral stent was removed.
LESSONS
This case indicated that ureteral obstruction and hydronephrosis caused by foreign bodies needed to be early diagnosed and located. Invasive therapies rather than conservative treatments are preferred to remove the FBs and relieve obstruction.
Topics: Adult; Female; Foreign Bodies; Humans; Hydronephrosis; Laparoscopy; Stents; Ureter; Ureteral Obstruction
PubMed: 31689845
DOI: 10.1097/MD.0000000000017780 -
Urolithiasis Dec 2022Ureteral obstruction after percutaneous nephrolithotomy (PCNL) may require prolonged drainage with a nephrostomy tube (NT) or ureteral stent, but it is not well...
BACKGROUND
Ureteral obstruction after percutaneous nephrolithotomy (PCNL) may require prolonged drainage with a nephrostomy tube (NT) or ureteral stent, but it is not well understood how and why this occurs. The goal of this study was to identify risk factors associated with postoperative ureteral obstruction to help guide drainage tube selection.
METHODS
Prospective data from adult patients enrolled in the Registry for Stones of the Kidney and Ureter (ReSKU) who underwent PCNL from 2016 to 2020 were used. Patients who had postoperative NTs with antegrade imaging-based flow assessment on postoperative day one (POD1) were included. Patients with transplanted kidneys or those without appropriate preoperative imaging were excluded. We assessed the association between patient demographics, stone characteristics, and intraoperative factors using POD1 antegrade flow, a proxy for ureteral patency, as the primary outcome. Stepwise selection was used to develop a multivariate logistic regression model controlling for BMI, stone location, stone burden, ipsilateral ureteroscopy (URS), access location, estimated blood loss, and operative time.
RESULTS
We analyzed 241 cases for this study; 204 (84.6%) had a visual clearance of stone. Antegrade flow on POD1 was absent in 76 cases (31.5%). A multivariate logistic regression model found that stones located anywhere other than in the renal pelvis (OR 2.63, 95% CI 1.29-5.53; p = 0.01), non-lower pole access (OR 2.81, 95% CI 1.42-5.74; p < 0.01), and concurrent ipsilateral URS (OR 2.17, 95% CI 1.02-4.65; p = 0.05) increased the likelihood of obstruction. BMI, pre-operative stone burden, EBL, and operative time did not affect antegrade flow outcomes.
CONCLUSION
Concurrent ipsilateral URS, absence of stones in the renal pelvis, and non-lower pole access are associated with increased likelihood of ureteral obstruction after PCNL. Access location appears to be the strongest predictor. Recognizing these risk factors can be helpful in guiding postoperative tube management.
Topics: Humans; Adult; Nephrolithotomy, Percutaneous; Ureteral Obstruction; Prospective Studies; Nephrostomy, Percutaneous; Kidney Calculi; Ureterolithiasis; Treatment Outcome
PubMed: 36239748
DOI: 10.1007/s00240-022-01365-8 -
Magnetic Resonance in Medicine Jan 2023To assess the potential of DCE MR CEST urography for assessing renal function in mice with unilateral ureter obstruction (UUO) by simultaneous pH and renal...
PURPOSE
To assess the potential of DCE MR CEST urography for assessing renal function in mice with unilateral ureter obstruction (UUO) by simultaneous pH and renal uptake/clearance measurements following injection of iopamidol.
METHODS
The right ureter of nine mice was obstructed via suture ligation. The animals were imaged at day 1, 2, and 3 post-obstruction on an 11.7T MRI scanner. Ninety-six sets of saturated CEST images at 4.3 and 5.5 ppm were collected. Renal pH values were obtained by calculating the signal ratio for these two frequencies and using a pH calibration curve. Renal time activity curves were measured as a percentage change in the post-injection CEST signal at 4.3 ppm relative to the average pre-injection signal.
RESULTS
For the healthy mice, the time activity curves of both kidneys were nearly identical and displayed rapid excretion of contrast. For the UUO mice, the dynamic CEST curves for the obstructed kidneys displayed prolonged time to peak (TTP) values and delayed contrast excretion compared with the contralateral (CL) kidneys. Renal pH maps of the healthy animals showed similar acidic values for both kidneys (pH 6.65 ± 0.04 vs 6.67 ± 0.02), whereas in the obstructed kidneys there was a significant increase in pH values compared with the CL kidneys (pH 6.67 ± 0.08 vs 6.79 ± 0.11 in CL and UUO kidneys, respectively).
CONCLUSION
Our findings indicate that DCE-MR-CEST urography can detect changes in renal uptake/excretion and pH homeostasis and distinguish between obstructed and unobstructed kidney as early as 1 day after UUO.
Topics: Animals; Mice; Ureter; Ureteral Obstruction; Kidney; Magnetic Resonance Imaging; Hydrogen-Ion Concentration; Urography
PubMed: 36089805
DOI: 10.1002/mrm.29436 -
In Vivo (Athens, Greece) 2020The aim of this review was to provide an update on the status of minimal invasive treatment of ureteral stricture either with a laparoscopic or robotic surgery. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND/AIM
The aim of this review was to provide an update on the status of minimal invasive treatment of ureteral stricture either with a laparoscopic or robotic surgery.
MATERIALS AND METHODS
Eligible studies, published until November 2019 were retrieved through Medline, Cochrane and Pubmed databases. Predetermined inclusion and exclusion criteria were used as selection method for data synthesis and acquisition. The study was performed in accordance with the PRISMA statement.
RESULTS
A total of 19 retrospective studies met the inclusion criteria. All of them demonstrated the safety, feasibility and success of both laparoscopic and robotic ureteral reconstruction. Individual case series or cumulative comparison analysis of the available studies showed at least equivalent success rates and a trend favoring laparoscopic and robotic groups in terms of estimated blood loss and length of hospital stay to the detriment of longer operative times and possibly higher cost.
CONCLUSION
Current evidence suggests the effectiveness, safety and increasing incorporation of minimally invasive techniques for complex stricture repair and reconstruction.
Topics: Constriction, Pathologic; Humans; Laparoscopy; Robotic Surgical Procedures; Treatment Outcome; Ureteral Obstruction
PubMed: 32354881
DOI: 10.21873/invivo.11864 -
Experimental and Clinical... May 2021Despite advances in surgical techniques and organ preservation, transplant ureteric strictures remain a common complication in kidney transplantation. A variety of...
OBJECTIVES
Despite advances in surgical techniques and organ preservation, transplant ureteric strictures remain a common complication in kidney transplantation. A variety of endourological and surgical techniques have been utilized; however, there is a lack of consensus on the optimal modality in dealing with these complex cases.
MATERIALS AND METHODS
We present challenging ureteral reconstruction cases after failed attempts at ureteral dilatation, failed conventional open repairs, and/or with bladder dysfunction.
RESULTS
All renal allografts were salvaged by successful use of bladder Boari flap and intestinal segment interpositions/diversions.
CONCLUSIONS
Operative repair remains the most durable and successful approach, and minimally invasive options should be reserved for nonsurgical candidates, with consideration of a single attempt in patients with early, distal, short (<2 cm), nonischemic strictures.
Topics: Constriction, Pathologic; Humans; Kidney Transplantation; Ureter; Ureteral Obstruction; Urinary Bladder
PubMed: 33797353
DOI: 10.6002/ect.2020.0566 -
Experimental and Clinical... Aug 2021The aim of our study was to evaluate the safety and efficacy of percutaneous treatment of ureteral obstructions and leak after renal transplant and to evaluate the...
OBJECTIVES
The aim of our study was to evaluate the safety and efficacy of percutaneous treatment of ureteral obstructions and leak after renal transplant and to evaluate the long-term results and graft survival rates in a single center.
MATERIALS AND METHODS
This retrospective study included 27 transplant recipients who received percutaneous treatment between January 2000 and December 2010 and who had follow-up data until December 2018. During this period, 294 renal transplants were performed at our institution, with 17 (5.7%) having a ureteral complication. Ten patients included in the study had their transplants at another center. Percutaneous nephrostomy, balloon dilatation, and double J stent placement were used in the management of complications. Cutting balloon dilatation and tandem ureteral stent placement were done in cases of resistant stenosis. Technical success and ureter patency rates were calculated. Graft survival rates were compared between early and late obstruction groups and between successful and unsuccessful interventional treatment.
RESULTS
Among included cases, 21 obstructions (7 early, 13 late) and 8 leaks were detected. The technical success rate of percutaneous nephrostomy was 100% in all groups. The technical success rates of balloon dilatation and double J stent were 100% and 88% in the early and late obstruction groups, respectively. Censored graft survival rates in all groups at 1, 5, and 10 years were 89%, 89%, and 73.9%, respectively. In long-term follow-up, ureter patency rates were 100%, 33%, and 50% for early obstruction, late obstruction, and urinary leak groups, respectively (P = .018). Graft survival rates between early and late obstruction groups were not significantly different. No major complication, allograft loss, or 30-day mortality was seen.
CONCLUSIONS
Percutaneous management of ureteral complications is safe and effective and should be considered as first-line treatment because of its less invasive nature and lower complication and morbidity rates.
Topics: Female; Humans; Kidney Transplantation; Male; Nephrostomy, Percutaneous; Postoperative Complications; Retrospective Studies; Stents; Treatment Outcome; Ureter; Ureteral Obstruction
PubMed: 32370698
DOI: 10.6002/ect.2019.0422 -
Annals of the Royal College of Surgeons... Jan 1972
Topics: Acute Kidney Injury; Colon; Dilatation; Female; Humans; Ileum; Methods; Postoperative Complications; Radiation Effects; Radiotherapy; Retroperitoneal Fibrosis; Tuberculosis, Urogenital; Ureter; Ureteral Calculi; Ureteral Diseases; Ureteral Neoplasms; Ureteral Obstruction; Ureterocele; Urinary Diversion; Urinary Tract Infections; Urography
PubMed: 5062021
DOI: No ID Found