Congenital Pelvi-ureteric Junction Obstruction Research Articles

Incidental detection of rare vascular variation during pyeloplasty and its clinical implication – A case report

Abstract Crossing vessels is one of the important causes of pelviureteric junction obstruction (PUJO). Accessory lower polar vessels are commonly seen with congenital PUJO, but they are not always the cause of obstruction. We incidentally encountered a variation in the lower polar crossing vessel while doing laparoscopic pyeloplasty in a patient with congenital PUJO. We encountered a right accessory lower polar artery and vein along with a right gonadal artery arising from the accessory right renal artery and right gonadal vein draining into the right lower polar crossing accessory renal vein. Knowledge of variations in genitourinary vasculature is important in the current era to prevent inadvertent complications.

Laparoscopic pyeloplasty as treatment modality for congenital pelvi-ureteric junction obstruction in children with pelvic kidney: case series

Laparoscopic pyeloplasty as treatment modality for congenital pelvi-ureteric junction obstruction in children with pelvic kidney: case series

Outcome of Dismembered Pyeloplasty in Children with Unilateral Pelviureteric Junction Obstruction: A Retrospective Observational Study

Introduction: Anderson-Hynes (AH) dismembered pyeloplasty is the standard procedure performed for the management of Pelviureteric Junction Obstruction (PUJO). Ultrasonography (USG) and diuretic renography are of great importance for the diagnosis and follow-up of PUJO. Aim: To evaluate the morphological and functional outcomes of open dismembered pyeloplasty in children with unilateral PUJO and to find the correlation between functional and morphological outcomes. Materials and Methods: A retrospective observational study was conducted, assessing the clinical charts of 200 children under 10 years of age with congenital PUJO who underwent open AH dismembered pyeloplasty in the Department of Paediatric Surgery at a teritary teaching Institute, Government medical college, Thiruvananthapuram, Kerala, India from from June 2015 to June 2020. The preoperative radiological assessment included renal USG and diuretic renography for all patients. Morphological and functional surgical outcomes were measured one year after surgery. The morphologic parameters analysed were the Anteroposterior Diameter (APD) of the pelvis and Parenchymal Thickness (PT). The functional outcome was assessed by improvements in Glomerular Filtration Rate (GFR), Split Renal Function (SRF), and drainage curve. Success was defined as improvement in function and morphology in followup USG and renogram after one year of surgery. Paired t-test was applied for statistical analysis using Statistical Package for the Social Sciences (SPSS) software version 23.0. Results: Among the total 200 patients,180 (90%) cases demonstrated improved renal function after pyeloplasty. Among the total 200 cases, males were 120 (60%) and females were 80 (40%). Morphologic outcome improved in 188 out of 200 (94%) cases. The overall outcome was good in 168 out of 200 (84%) patients. The results showed a moderate negative correlation for APD with respect to SRF (r=-0.677, p-value=0.01) and GFR (r=- 0.430, p-value=0.01), whereas a moderate positive correlation was observed between SRF and GFR (r=0.423, p-value=0.01). Conclusion: AH dismembered pyeloplasty is an effective treatment for PUJO in children, not only relieving obstruction but also improving renal function. The present study recommends considering both morphologic and functional parameters to assess the success of the surgery.

Study to Assess for Improvement in Renal Function following Anderson Hynes Pyeloplasty for Congenital Pelvi Ureteric Obstruction in Children

Background: Pelvi Ureteric Junction Obstruction (PUJO) is defined as an obstruction to the free flow of urine from the renal pelvis to the proximal ureter1. It is the most common cause of obstructive uropathy in the paediatric age group. Aims: To check for improvement in renal function following Anderson Hynes pyeloplasty for congenital PUJ obstruction and to find out at what age should a child be operated for best improvement in renal functions. Material and Methods: A total of 20 patients undergoing Anderson Hynes Pyeloplasty were included after they satisfied the inclusion and exclusion criteria. Results: In this study it was observed that post Anderson Hynes pyeloplasty, a total of 60% children showed improvement in renal functions, in 30% there was no change in renal function while 10% showed deterioration in renal functions, requiring re-operation. The improvement was statistically significant Mean eGFR in cases improved from 32.25 to 38.5 mL/min/1.73 m2 after Anderson Hynes pyeloplasty. The improvement was statistically significant Mean renal functions in cases improved from 29.05% to 33.7% after Anderson Hynes pyeloplasty. No complications were reported in 85% of the cases after Anderson Hynes pyeloplasty. UTI developed in 2 cases (10%) while pyonephrosis was seen in 1 case (5%). Conclusion: Anderson Hynes Pyeloplasty is an effective treatment for congenital Pelvi Ureteric Junction obstruction in pediatric population. In this study it was observed that the earlier we operate the better is the improvement in function.

Etiology of symptomatic upper urinary tract obstruction in southeast Nigeria

Background: The causes of upper urinary tract (UUT) obstruction vary from one geographical location to another, and across gender and age. Similarly, the site of obstruction along the ureter varies with the nature of the obstructing lesion. Data in this regard from southeast Nigeria are deficient. Objective: To determine the causes of symptomatic UUT obstruction in southeast Nigeria. Materials and Methods: The medical records of individuals with confirmed UUT obstruction presenting from January 2011 to November 2017 were reviewed for information on the cause and location of obstruction. In addition, the pattern of the obstructions caused by UUT stones was compared across the gender and age of individuals. All statistical analyses were done using SPSS® version 21. Results: The medical reports of 267 individuals are included for analysis. Overall, urinary stone is the most prevalent cause of UUT obstruction, with a male-to-female ratio of 1.25. From 50 years of age onward, obstructing UUT stones are commoner in females (χ2 = 5.03; P = 0.03). In addition, obstructing UUT stones are more common on the right (55.1%) and in the upper ureter (48.9%) in univariate analyses. Congenital pelvi-ureteric junction (PUJ) obstruction is observed to be the most prevalent congenital cause of UUT obstruction. Uterine fibroids in females and advanced prostate cancer in males are also notable causes of ureteric obstruction. Conclusion: Beyond urinary stone and congenitally defective PUJ, uterine fibroids and prostate cancer are other notable causes of ureteric obstruction in southeast Nigeria.

Congenital Pelvi-ureteric Junction Obstruction Associated with Crossing Lower Pole Vessels

Background: Congenital pelvi-ureteric junction obstruction [PUJO] occurs when there is impairment of flow of urine from the renal pelvis to the proximal ureter due to inherited abnormalities of pelvi-ureteric junction [PUJ]. The presentation is usually at the 4th or 5th decade of life. It may rarely be associated with crossing lower pole vessel [CLPV]. Treatment is by Anderson- Hynes [dismembered] pyeloplasty which remove the abnormal PUJ and transposes the PUJ anterior to the offending vessels. I report a case of 45-year-old man with congenital PUJO associated with crossing lower pole vessel vessels who had dismembered Anderson -Hynes pyeloplasty.

Sigmoid volvulus: mischief from a gravid uterus

A 39‐year‐old gravida 2 para 1 female at 32 weeks gestation presented with 3 days of abdominal pain, distension, nausea and diarrhoea. Her presentation was associated with tenesmus and anorexia. Her past history was significant for an elective laparoscopic left‐sided pyeloplasty for congenital pelviureteric junction obstruction. On examination, the patient was afebrile and haemodynamically stable. The foetus was not distressed according to cardiotocography assessment. Her abdomen was distended and tympanic with generalized tenderness. Bowel sounds were high pitched and tinkling. A digital rectal examination revealed an empty rectum with no masses or faeces. The patient was hypokalaemic and hyponatraemic at 3.1 and 129 mmol/L, respectively. Her white cell count was 20.3 × 109/L, of which 17.87 × 109/L were neutrophils. Abdominal plain films were concerning for a large bowel obstruction, with marked distension of large bowel proximal to the descending colon and an absence of gas in the left lower quadrant (Fig. 1). A nasogastric tube was placed with minimal effect on symptomology and a magnetic resonance imaging (MRI) was performed. This demonstrated spiralling of the sigmoid colon at the transition point of the obstruction, concerning for a sigmoid volvulus (Figs 2, 3). Initial attempt at decompression with rigid sigmoidoscopy failed. Colonoscopic decompression was performed, successfully reducing the volvulus. The entire length of colon had viable mucosa on endoscopic examination. A flatus tube was placed during the procedure and removed on the following day. Her condition improved, and she was discharged on the third day.

Neuronal defects an etiological factor in congenital pelviureteric junction obstruction?

Congenital pelviureteric junction obstruction (PUJO) is one of the most frequent causes of neonatal hydronephrosis. Obstruction at the PUJ has potential severe adverse outcomes, such as renal damage. While pyeloplasty has been established as the definitive treatment, the exact pathophysiology of congenital PUJO remains unknown. Recent research has proposed neuronal innervation defects as an etiological factor in congenital PUJO. We aim to study the expression of various neuronal markers in PUJO specimens compared with controls, and evaluate whether severity of renal disease or dysfunction pre-operatively is related to expression of neuronal markers in resected PUJO specimens. All consecutive patients who underwent dismembered pyeloplasty at KK Women's and Children's Hospital, Singapore, for intrinsic PUJO from 2008 to 2012 were included. Patients with other co-occurring renal pathologies were excluded. Controls were obtained from nephrectomy patients with Wilm's tumor or other benign renal conditions during the same period. Specimens were stained immunohistochemically with neuronal markers protein gene product 9.5 (PGP9.5), synaptophysin, and S-100, and with CD-117, a marker for interstitial cells of Cajal (Table). Levels of expression of the markers were assessed semiquantitatively (decreased, increased or no change) in comparison with controls by two independent observers. Pre-operative data of patients' renal anatomical (ultrasonography measurements of renal pelvis size) and functional parameters (differential renal function measured using MAG-3 renal scans) were obtained. Thirty-eight PUJO specimens (38 renal units) and 20 controls were studied. Mean patient age at pyeloplasty was 25.3 months (2.9-167.6 months). Median pre-operative pelvic size was 25.0mm (17.0-50.0mm). Both PUJO specimens and controls showed great heterogeneity in distribution of innervation. All four immunohistochemical markers were not predictive of significant pre-operative renal pelvis dilation or pre-operative diminished renal function of the operated kidney. There exists marked variability in expression of neuronal markers synaptophysin, PGP9.5, and S-100, and CD-117 in PUJO specimens compared with controls. Our results show no clinical significance of the expression of neuronal markers in predicting degree of pre-operative renal pelvis dilation or differential renal function. The heterogeneity of expression of neuronal markers in PUJO specimens and controls in our population is at variance with prior studies. The etiology of PUJO is likely to be complex and multifactorial.

Commentary to “Neuronal defects an etiological factor in congenital pelviureteric junction obstruction?”

Commentary to “Neuronal defects an etiological factor in congenital pelviureteric junction obstruction?”

The Expression of Gli3 and Teashirt3 in the Stenotic Tissue of Congenital Pelvi-Ureteric Junction Obstruction in Children.

Background: The aim of this study was to determine the expression pattern of Gli3 and Teashirt3 in stenotic segments in children with congenital hydronephrosis due to pelvi-ureteric junction obstruction (PUJO) versus in normal control subjects.Materials and methods: 60 patients and 10 controls were included in this study. Immunohistochemistry, Western blot and real-time PCR were used to investigate into the expression of Gli3 and Teashirt3.Results: Immunohistochemistry identified that Gli3 and Teashirt3 located in the cytoplasm of smooth muscle in normal ureter. However, the expression of Gli3 and Teashirt3 was negative in the PUJO group. Gli3 and Teashirt3 protein and mRNA expression was significantly decreased in PUJO group compared with control group on Western blot and real time PCR.Conclusions: The expression of protein and mRNA of Gli3 and Teashirt3 was significantly decreased in the PUJO group. Gli3 and Teashirt3 protein was mainly located in the cytoplasm of smooth muscle in normal ureter. Gli3 and Teashirt3 might play an important role in the normal development of the ureter. The down-regulated Gli3 and Teashirt3 perhaps participated in the pathogenesis of the congenital hydronephrosis due to PUJO.

Review of appendiceal onlay flap in the management of complex ureteric strictures in six patients

To evaluate appendiceal onlay flap ureteroplasty for repairing complex right proximal and mid-ureteric strictures. Between August 2006 and August 2012 four women and two men (mean age 34.2 years) underwent right laparoscopic appendiceal onlay flap ureteroplasty. The mean stricture length was 2.5 cm. Stricture formation was secondary to impacted ureteric stones in three patients and failed pyeloplasty for congenital pelvi-ureteric junction obstruction in the remaining three. Each patient had ipsilateral flank pain before surgery. The mean operating time, estimated blood loss and hospital stay were 244 min, 175 mL and 3.2 days, respectively. No intra- or peri-operative complications were noted. The objective success rate was 100% (all patients had radiographic and/or endoscopic resolution of their ureteric strictures). The subjective success rate was 66%, (two patients developed recurrent discomfort, which upon exploration was found to be attributable to fibrosis away from the appendiceal onlay graft, where the gonadal vessels crossed the ureter). Both patients with recurrent pain underwent laparoscopic ureterolysis and bladder advancement flap proximal to the appendiceal onlay, which markedly improved one patient's pain but the other patient continued to have discomfort, ultimately resulting in a laparoscopic nephroureterectomy. Appendiceal onlay ureteroplasty is a viable treatment option for patients with complex right proximal and mid-ureteric strictures, while minimising the potential morbidity of appendiceal and ileal interposition.

Post A-H Pyeloplasty Analysis of Renal Function in Unilateral Hydronephrosis Due to Congenital Pelviureteric Junction Obstruction

Background: The objective of this study was to analyze the functional improvement of renal function in terms of split renal function (SRF) & glomerular filtration rate (GFR) by DTPA renogram in early post operative period who underwent A-H pyeloplasty for unilateral hydronephrosis due to congenital pelvi ureteric junction obstruction.Methods: A prospective observational study was conducted to see the post operative renal function improvement in patient with unilateral hydronephrosis due to congenital pelvi ureteric junction obstruction in department of paediatric surgery, BSMMU from July 2007 to October 2008. All the patients were followed up at 4 weeks interval for 12 weeks.Results: Total 13 Patients both male & female were observed with age ranging from 03 months to 15 years. Out of 13, eleven patients showed gradual improvement of renal function in terms of SRF & GFR in three successive DTPA renogram done at 4, 8 & 12 weeks post operatively but two patients showed deterioration of renal function in 1st two renogram but improved at 12th weeks period.Conclusion: DTPA renogram is the best method to see the functional improvement of renal function after A-H pyeloplasty but should be done on 12th post operative day.DOI: http://dx.doi.org/10.3329/jpsb.v2i2.19543

Defining the pros and cons of open, conventional laparoscopy, and robot-assisted pyeloplasty in a developing nation.

Introduction. Congenital pelviureteric junction obstruction (PUJO) is one of the most common causes of hydronephrosis. Historically, open dismembered pyeloplasty has been considered the gold standard intervention for correcting PUJO. The aim of this study was to compare the surgical and functional outcomes of three different approaches, namely, open, conventional laparoscopy, and robotic pyeloplasty. Material and Methods. 60 patients underwent minimally invasive pyeloplasty (30 conventional laparoscopies and 30 robotics) for congenital PUJO at a tertiary health center in India. Demographic, perioperative, and postoperative data were prospectively collected and analyzed. The data of these patients were retrospectively compared with another cohort of 30 patients who had undergone open pyeloplasty. Results. There was significant difference in operative time, time to drain removal, hospital stay, pain score, and complications rate between open and minimally invasive pyeloplasty (P < 0.05). SFI was considerably lesser in robotic as compared to conventional laparoscopy. The success rate in OP, CLP, and RP was 93.33, 96.67, and 96.67%. Conclusion. Robotic pyeloplasty is safe, effective, and feasible. It is associated with significantly lesser operative time, lesser blood loss, less pain, shorter hospital stay, and fewer complications. It is also associated with considerably lesser surgeon fatigue as compared to conventional laparoscopy pyeloplasty.

Transperitoneal Nephrectomy of Hydronephrotic Tubercular Kidney: A Rare Case Report

Genitourinary tuberculosis (GUTB) is the second most common form of extrapulmonary tuberculosis, with more than 90% of cases occurring in developing countries. As tuberculosis causes complete destruction of the kidney, the giant hydronephrosis, due to tuberculosis, is a rare condition. Although the role of surgery in GUTB has decreased since the advent of anti-TB therapy, it can still have a role as an adjunct to drug treatment. A 65-year-old male presented with a huge abdomen. Clinical diagnosis of congenital pelvi-ureteric junction (PUJ) obstruction was made, and percutaneous nephrostomy was done to save the function of the kidney. Ultrasound and computed tomography (CT) confirmed the diagnosis. As it turned out to be a nonfunctioning kidney, transperitoneal laparoscopic nephrectomy was done. A histopathological report of the removed kidney revealed renal tuberculosis. Tubercular PUJ stricture presenting as giant hydronephrosis is uncommon; we thus present this case.

The expression of Cajal cells at the obstruction site of congenital pelviureteric junction obstruction and quantitative image analysis

Objective The study aimed to analyze the expression and significance of interstitial cells of Cajal (ICC) at the obstruction site of congenital pelviureteric junction obstruction (PUJO). Methods Specimens of the strictured segment of the PUJ were obtained from 24 patients who were diagnosed to have PUJO (without aberrant vessels and adhesive band compression of ureteral junction) intraoperatively. In the control group, PUJ specimens were taken from 21 patients who had Wilms' tumor. Pelviureteric junction tissues were confirmed to be free of tumor invasion by histology. Immunohistochemistry with c-kit antibody was performed to detect the expression of ICC in specimens of the 2 groups. Quantitative analysis was made using image analysis technique and statistical analysis was carried out. Results Immunoreactivity to ICC was predominantly detected in the muscle layers of PUJ. The mean area of ICC expression in the PUJO group was 14.86 ± 1.37 × 10 4 μm 2 , which was lower than that in the control group (16.80 ± 1.68) × 10 4 μm 2 ( P < .01). The mean density of ICC expression in the PUJO was 0.207 ± 0.020, which was also lower than that in the control group (0.262 ± 0.026) ( P < .05). Conclusions A reduction of the number of ICC may play an important role in the etiology and pathogenesis of PUJO.

Ureter Myogenesis

After the basic shape of the mammalian ureter is established, its epithelia mature and a coat of smooth muscle cells differentiate around nascent urothelia. The ureter actively propels tubular fluid from the renal pelvis to the bladder, and this peristalsis, which starts in the fetal period, requires coordinated smooth muscle contraction. Teashirt-3 (Tshz3) is expressed in smooth muscle cell precursors that form the wall of the forming mammalian ureter. The Teashirt gene family was first identified in Drosophila where Teashirt (Tsh) protein acts as a transcription factor directing embryonic anterior-posterior patterning and leg and eye development. In fly embryonic renal tubules, Tsh is expressed in mesodermally derived stellate cells intercalating between principal cells, and a paralogue, tiptop, is expressed in forming tubules. Teashirt is a component of several gene networks in flies and it is notable that similar networks control mammalian renal tract development. Null mutation of Tshz3 in mice leads to failure of functional muscularization in the top of the ureter and this is followed by congenital hydronephrosis. A signaling pathway can be envisaged, starting with sonic hedgehog secreted by the nascent ureteric urothelium and ending with ureteric smooth muscle cell differentiation, with Tshz3 downstream of bone morphogenetic protein 4 and upstream of myocardin and smooth muscle cell contractile protein synthesis. The phenotype of Tshz3 mutant mice resembles that of human congenital pelviureteric junction obstruction, and we suggest these individuals may have mutations of genes encoding molecules in the differentiation pathway mediated by Tshz3.

Analysis of TSHZ2 and TSHZ3 genes in congenital pelvi-ureteric junction obstruction.

Congenital pelvi-ureteric junction obstruction (PUJO) affects 0.3% of human births. It may result from aberrant smooth muscle development in the renal pelvis, resulting in hydronephrosis. Mice that are null mutant for the Teashirt3 (Tshz3) gene exhibit congenital PUJO with defective smooth muscle differentiation and absent peristalsis in the proximal ureter. Given the phenotype of Tshz3 mutant mice, we considered that Teashirt genes, which code for a family of transcription factors, might represent candidate genes for human PUJO. To evaluate this possibility, we used in situ hydridization to analyse the three mammalian Tshz genes in mouse embryonic ureters and determined whether TSHZ3 was expressed in the human embryonic ureter. TSHZ2 and TSHZ3 were sequenced in index cases with non-syndromic PUJO. Tshz2 and Tshz3 genes were detected in mouse ureters and TSHZ3 was expressed in the human embryonic renal pelvis. Direct sequencing of TSHZ2 and TSHZ3 did not identify any mutations in an initial cohort of 48 PUJO index cases, excluding these genes as a major cause of this condition. A polymorphic missense change (E469G) in TSHZ3 was identified at a residue highly conserved throughout evolution in all Teashirt proteins, although subsequently no significant difference between the E469G allele frequency in Albanian and Macedonian PUJO index cases (3.2%) versus 633 control individuals (1.7%) was found (P = 0.18). Mutations in TSHZ2 and TSHZ3 are not a major cause of PUJO, at least in Albanian and Macedonian populations. Expression of these genes in the human fetal ureter emphasizes the importance of analysing these genes in other groups of patients with renal tract malformations.

Giant Obstructive Megaureter Causing Contralateral Ureteral Obstruction and Hydronephrosis: A First-time Report

We report for the first time a "giant megaureter" causing symptomatic compression of the contralateral ureter in a 15-year-old girl. Extrinsic compression of the ureter by a contralateral giant hydronephrotic kidney, although rare, has been reported most commonly because of congenital pelviureteric junction obstruction. In this case, the possible etiology of megaureter, the differential diagnosis, and the clinical implications are discussed.

Teashirt 3 is necessary for ureteral smooth muscle differentiation downstream of SHH and BMP4

Ureteric contractions propel foetal urine from the kidney to the urinary bladder. Here, we show that mouse ureteric smooth muscle cell (SMC) precursors express the transcription factor teashirt 3 (TSHZ3), and that Tshz3-null mutant mice have congenital hydronephrosis without anatomical obstruction. Ex vivo, the spontaneous contractions that occurred in proximal segments of wild-type embryonic ureter explants were absent in Tshz3 mutant ureters. In vivo, prior to the onset of hydronephrosis, mutant proximal ureters failed to express contractile SMC markers, whereas these molecules were detected in controls. Mutant embryonic ureters expressed Shh and Bmp4 transcripts as normal, with appropriate expression of Ptch1 and pSMAD1/5/8 in target SM precursors, whereas myocardin, a key regulator for SMC differentiation, was not expressed in Tshz3-null ureters. In wild-type embryonic renal tract explants, exogenous BMP4 upregulated Tshz3 and myocardin expression. More interestingly, in Tshz3 mutant renal tract explants, exogenous BMP4 did not improve the Tshz3 phenotype. Thus, Tshz3 is required for proximal ureteric SMC differentiation downstream of SHH and BMP4. Furthermore, the Tshz3 mutant mouse model of ;functional' urinary obstruction resembles congenital pelvi-ureteric junction obstruction, a common human malformation, suggesting that TSHZ, or related, gene variants may contribute to this disorder.

Renal tract malformations: perspectives for nephrologists

Renal tract malformations are congenital anomalies of the kidneys and/or lower urinary tract. One challenging feature of these conditions is that they can present not only prenatally but also in childhood or adulthood. The most severe types of malformations, such as bilateral renal agenesis or dysplasia, although rare, lead to renal failure. With advances in dialysis and transplantation for young children, it is now possible to prevent the early death of at least some individuals with severe malformations. Other renal tract malformations, such as congenital pelviureteric junction obstruction and primary vesicoureteric reflux, are relatively common. Renal tract malformations are, collectively, the major cause of childhood end-stage renal disease. Their contribution to the number of adults on renal replacement therapy is less clear and has possibly been underestimated. Renal tract malformations can be familial, and specific mutations of genes involved in renal tract development can sometimes be found in affected individuals. These features provide information about the causes of malformations but also raise questions about whether to screen relatives. Whether prenatal decompression of obstructed renal tracts, or postnatal initiation of therapies such as prophylactic antibiotics or angiotensin blockade, improve long-term renal outcomes remains unclear.