Ureteric valve: Case report with an insight into anatomy, embryology, presentation and management.
Gupta Rahul K,Borwankar S S,Parelkar Sandesh V
Indian journal of urology : IJU : journal of the Urological Society of India
Congenital ureteric obstruction caused by a ureteric valve is an exceedingly rare entity. Our patient, a nine-year-old male, had undergone evaluation for recurrent pain in the abdomen and was diagnosed as a case of left hydronephrosis on ultrasound abdomen. Intravenous urography and magnetic resonance urography showed incomplete duplex system on the right side along with left hydronephrosis and hydroureter. Cystoscopy with left ascending gram followed by excision of lower third of ureter along with valve and Cohen's ureteroneocystostomy was done. Histopathology revealed Type II ureteric valve. A high index of suspicion is required to make a correct preoperative diagnosis.
The Morphology of Congenital Dilatation of the Ureter: Intrinsic Ureteral Lesions.
Cussen L J
The Australian and New Zealand journal of surgery
Congenitally dilated ureters are divided into four groups associated with (i) intrinsic ureteral lesions, (ii) vesico-ureteral reflux, (iii) urethral obstruction or (iv) other malformations such as myelomeningocele or the triad syndrome. One hundred and forty-seven dilated ureters in Group 1 (caused by Intrinsic ureteral lesions), have been studied qualitatively and quantitatively by standard pathological techniques, using the average size and population of muscle cells in the dilated ureter as the quantitative index of work-load or obstruction, and have been divided into four main types. These dilated ureters were found to be either obstructed or non-obstructed, and the obstructing lesion was either an atresia, a stenosis, or a valve. In each of the obstructed ureters, the smooth muscle in the wall of the proximal dilated ureter was hypertrophic and hyperplastic. In contrast, in the fourth non-obstructed type of dilated ureter, no obstructing lesion was found, and there was neither hypertrophy nor hyperplasia of muscle in the wall of the proximal dilated ureter; it is presumed that the dilatation is due to developmental lateral overgrowth of the ureter. No example of dilated ureter due to neuro-muscular incoordination was found in this group.
Bladder contractility index in posterior urethral valve: A new marker for early prediction of progression to renal failure.
Ansari M S,Nunia Sandeep Kumar,Bansal Ankur,Singh Prempal,Sekhon Virender,Singh Dharmveer,Soni Rahul,Yadav Priyank
Journal of pediatric urology
INTRODUCTION:Posterior urethral valve (PUV) is the most common cause of pediatric end stage renal disease (ESRD), imposing a major health burden on medical community caregivers and adversely affecting the quality of life of patients. Chronic kidney disease (CKD) stage III or estimated GFR of <60 mL/min/1.73 m is known to be associated with more adverse renal, cardiovascular, and clinical outcomes. Thus, it is desirable to identify factors predicting the rapid and early progression of disease. In the present study, baseline characteristics and urodynamic study (UDS) parameters of boys with PUV are correlated with CKD progression to IIIB or more. AIMS AND OBJECTIVES:To study the correlation of bladder contractility index (BCI) with development of CKD stage IIIB (eGFR of <45 mL/min/1.73 m) or more in boys with PUV. METHODOLOGY:Baseline characteristics and demographical variables of 270 boys with PUV who underwent valve fulguration at the hospital between 2000 and 2010 were recorded and certain UDS parameters in follow-up were noted such as bladder contractility index (BCI = PdetQmax + 5 Qmax), end filling pressure (EFP), compliance (ΔC), bladder outlet obstruction index (BOOI = Pdet Qmax - 2 Qmax), and bladder volume efficiency (BVE = Voided volume/total capacity). Fate of patients in follow-up was checked in December 2015. RESULTS:Mean follow-up period was 8.5 years (range 5-15) and median age of patients at the time of evaluation was 5.8 years. At the end of the study, 21.8% (59/270) of patients had progressed to CKD stage IIIB or more (primary end point). Cox regression analysis was applied to risk factors predicting development of CKD stage IIIB. In the multivariate model, bladder contractility index (BCI) (HR 0.8; p = 0.004), end filling pressure (EFP) (HR 2.1; p = 0.010), and compliance (ΔC) (p = 0.020) were significantly associated with the event (i.e. an eGFR of <45 mL/min/1.73 m), whereas BOOI (p = 0.053) and bladder BVE (p = 0.267) were not. ROC cut-off level for BCI predicting the primary end point was 75 (AUC ± SE, 0.73 ± 0.03, sensitivity of 78.2%, and specificity of 62.5%). CONCLUSION:In a well performed UDS, BCI may be a useful tool for early detection of boys with PUV who are likely to progress to CKD stage IIIB or more.
The development of the bladder trigone, the center of the anti-reflux mechanism.
Viana Renata,Batourina Ekatherina,Huang Hongying,Dressler Gregory R,Kobayashi Akio,Behringer Richard R,Shapiro Ellen,Hensle Terry,Lambert Sarah,Mendelsohn Cathy
Development (Cambridge, England)
The urinary tract is an outflow system that conducts urine from the kidneys to the bladder via the ureters that propel urine to the bladder via peristalsis. Once in the bladder, the ureteral valve, a mechanism that is not well understood, prevents backflow of urine to the kidney that can cause severe damage and induce end-stage renal disease. The upper and lower urinary tract compartments form independently, connecting at mid-gestation when the ureters move from their primary insertion site in the Wolffian ducts to the trigone, a muscular structure comprising the bladder floor just above the urethra. Precise connections between the ureters and the trigone are crucial for proper function of the ureteral valve mechanism; however, the developmental events underlying these connections and trigone formation are not well understood. According to established models, the trigone develops independently of the bladder, from the ureters, Wolffian ducts or a combination of both; however, these models have not been tested experimentally. Using the Cre-lox recombination system in lineage studies in mice, we find, unexpectedly, that the trigone is formed mostly from bladder smooth muscle with a more minor contribution from the ureter, and that trigone formation depends at least in part on intercalation of ureteral and bladder muscle. These studies suggest that urinary tract development occurs differently than previously thought, providing new insights into the mechanisms underlying normal and abnormal development.
[A case of valve-like structure in ureter associated with pyonephrosis due to Salmonella infection].
Ogura Y,Kameda K,Hayashi N,Arima K,Yamagawa M,Kawamura J
Hinyokika kiyo. Acta urologica Japonica
A 7-year-old boy had a fever of 39 degrees C. Abdominal computed tomography (CT) revealed marked left hydronephrosis with hydroureter. Percutaneous nephrostomy was performed. Salmonella infanitis was detected from the drainage urine. Cystourethrography after nephrostomy showed bilateral vesicoureteral reflex (VUR). On the left side, ureteropelvic junction (UPJ) stenosis was found. Left fistelography showed hydronephrosis, but the ureter was not visualized. A mechanism like a valve at the left UPJ was suggested; the bladder urine was able to ascend to the pelvis but not to be drained from the pelvis. The left renal function was not expected to recover from the findings of renal scintigram and CT. Left nephroureterectomy and right anti-VUR operation were performed. The extirpated renal and ureteral specimens revealed a nonpapillary tumorous structure like a valve at the left UPJ. The histological examination of the valve-like structure revealed the presence of two muscle layers without an adventitia folded at the UPJ.
An electron microscopic examination of the intravesical ureter in children with primary vesico-ureteric reflux.
Sofikerim Mustafa,Sargon Mustafa,Oruc Ozgur,Dogan Hasan S,Tekgul Serdar
OBJECTIVE:To determine the structure of the intravesical distal ureteric wall of patients with primary vesico-ureteric reflux (VUR), and to compare the findings with previous reports. MATERIALS AND METHODS:Specimens of the distal intravesical ureteric segments were taken surgically from children undergoing ureteric reimplantation surgery for primary VUR. There were 24 distal intravesical ureteric specimens from 15 children (nine female and six male). Ultra-thin sections were cut from the specimens and examined with a transmission electron microscope. RESULTS:The appearance of the muscular layers of the specimens of different grades differed markedly. There were intercellular oedematous areas in the muscular layer in specimens from patients with grade 2 and 3 VUR. In specimens from grade 4 VUR there were also intracytoplasmic vacuoles in the smooth muscle cells. The most marked and striking changes were in the specimens from children with grade 5 VUR, in which there were large intercellular oedematous areas and prominent large intracytoplasmic vacuoles. CONCLUSION:Refluxing ureters differ from normal ureters in having disorganized smooth muscle fibres and altered smooth muscle cell structure, leading to incompetence of the valve mechanism. Although we cannot confirm that these pathological changes in the smooth muscle layer of the intravesical ureteric wall are caused by VUR we conclude that, with increasing degrees of reflux, the degree of smooth muscle damage increases, and that the rate of spontaneous resolution decreases.
Ultrastructural and immunohistopathological evaluation of intravesical ureters via electron and light microscopy in children with vesicoureteral reflux.
Izol Volkan,Acikalin Arbil Avci,Kuyucu Yurdun,Deger Mutlu,Aridogan Ibrahim Atilla,Polat Sait,Satar Nihat
The Journal of urology
PURPOSE:We used immunohistochemical methods and transmission electron microscopy to investigate the cytokine profiles and ultrastructural changes in the ureterovesical junction of children with primary vesicoureteral reflux. MATERIALS AND METHODS:A total of 39 distal intravesical ureters were obtained from 23 children who underwent ureteroneocystostomy for primary vesicoureteral reflux. Ureteral wall smooth muscle organization and transforming growth factor-β1, vascular endothelial growth factor and CD34 were evaluated immunohistochemically and compared to controls, which consisted of 10 age matched autopsy specimens. Ultrastructural evaluations and morphological descriptions were performed semiquantitatively and compared to the published data. RESULTS:Of the patients 6 (26%) were male and 17 (74%) were female, and mean ± SD age was 73.2 ± 34.3 months (range 12 to 168). There was no correlation between reflux grade and age (p = 0.39). Smooth muscle disorganization score differed significantly between patients with intravesical ureters and controls (p = 0.01). Transforming growth factor-β1 levels were significantly higher (p = 0.001) and vascular endothelial growth factor levels and microvessel densities were significantly lower in the patients with reflux compared to controls (both p <0.001). Vascular endothelial growth factor, CD34 and transforming growth factor-β1 levels did not correlate with reflux grades (p = 0.84, p = 0.76 and p = 0.10, respectively). Urothelium, lamina propria and tunica adventitia appeared normal in the specimens for all grades of vesicoureteral reflux using transmission electron microscopy. Damage was observed in the muscular layers of the ureterovesical junction, especially in patients with grade IV or V reflux. CONCLUSIONS:Primary refluxing ureters exhibit immunohistopathological abnormalities compared to normal ureters irrespective of reflux grade, and ultrastructural changes are especially severe in cases of high grade reflux. These abnormalities can hinder the normal ureteral valve mechanism, and may lead to reflux due to smooth muscle dysfunction and microvascular alterations.
The intravesical ureter in children with vesicoureteral reflux: a morphological and immunohistochemical characterization.
Oswald Josef,Brenner Erich,Schwentner Christian,Deibl Martina,Bartsch Georg,Fritsch Helga,Radmayr Christian
The Journal of urology
PURPOSE:We investigated intravesical ureteral endings using immunohistochemical methods to study general morphology, smooth muscle architecture and collagen composition in children with vesicoureteral reflux. MATERIALS AND METHODS:Samples were obtained from 29 ureterorenal units in children with a mean age of 52.3 months undergoing reflux surgery. Routine histological paraffin embedded sections were stained with hematoxylin and eosin, and Masson trichrome to assess general morphology. Staining for actin, myosin and desmin was performed to evaluate the presence, allocation and architecture of the ureteral smooth muscle wrap. In addition, indirect immunohistochemical methods were used to study the collagen composition of the ureteral wall and CD68 was used for macrophage labeling as a marker of tissue remnant scavenging. All investigations were done using high power field magnification for quantification. In addition, age matched, nonrefluxing ureteral specimens served as controls. RESULTS:Smooth muscle alpha-actin, myosin and desmin expression were extensively decreased in all specimens pertaining to the ureteral ending. This distal part showed a high degree of muscle atrophy and degeneration as well as a disordered fiber arrangement associated with increased extracellular matrix collagen accumulation. In addition, CD68 positive macrophages were significantly increased. In contrast to these observations, the proximal intravesical portion of the ureter showed intact morphology and arrangement of the muscular coat. CONCLUSIONS:Refluxing intravesical ureteral endings showed dysplasia, atrophy and architectural derangement of smooth muscle fibers. Consequently symmetrical contraction of the distal ureteral smooth muscle coat creating the active valve mechanism to protect reflux is not achievable.
Structural changes of the intravesical ureter in children with vesicoureteral reflux-does ischemia have a role?
Schwentner C,Oswald J,Lunacek A,Schlenck B,Berger A P,Deibl M,Fritsch H,Bartsch G,Radmayr C
The Journal of urology
PURPOSE:Previous studies have revealed structural and metabolic changes in the distal most ureter, impairing its contractile properties, and, thus, having a role in the pathogenesis of vesicoureteral reflux. Musculature and nerves are replaced by interstitial collagen, while matrix degrading enzymes are over expressed. We investigated the microvessel architecture of the ureterovesical junction to elucidate further the pathophysiology of vesicoureteral reflux. MATERIALS AND METHODS:Ureteral endings were obtained from 28 children during antireflux surgery. Ureteral tissue from 14 age matched autopsy specimens served as control. Routine histological paraffin embedded sections were immunostained, detecting CD31 as an endothelial marker as well as vascular endothelial growth factor. Microvessel density and vascular endothelial growth factor expression were investigated based on computer assisted high power field magnification analyses. The t test and the Spearman rho test were applied for statistical evaluation. RESULTS:Overall, microvessel density was significantly reduced in cases of vesicoureteral reflux. While reflux grade and age were not correlated with microvessel density, it was particularly decreased in regions lacking smooth musculature. Vascular endothelial growth factor was observed in smooth muscle, endothelial and connective tissue cells. Additionally, cellular vascular endothelial growth factor expression was markedly abridged in cases of vesicoureteral reflux compared to healthy controls. CONCLUSIONS:Overall microperfusion is supposed to be impaired, leading to tissue ischemia due to reduction of vascular endothelial growth factor expression and subsequent microvessel density. Diminished ureteral perfusion is likely to induce and support smooth muscle dysfunction as well as subsequent extracellular matrix remodeling, including increased collagen deposition. These ongoing functional and structural alterations may further deteriorate the active valve mechanism of the ureterovesical junction, causing vesicoureteral reflux.