Bladder calculi in augmentation cystoplasty in children

Metabolic consequences and tubular function after augmentation cystoplasty in children with neurogenic bladder

BACKGROUND

While many studies have reported the renal outcomes and metabolic consequences of augmentation cystoplasty (AC), few have focused on changes in renal tubular function. This study investigated the prevalence of metabolic disturbances, renal tubular function, and 24-hour urine chemistry, aiming to evaluate the association between metabolic alterations and urolithiasis after AC.

METHODS

We investigated serum biochemistry, blood gas, and 24-hour urinary metabolic profile of children who underwent AC between January 2000 and December 2020. The assessed outcomes included metabolic complications, tubular function, and magnesium status. Associations between 24-hour urinary metabolic parameters and urolithiasis formation were also examined.

RESULTS

A total of 25 patients with a mean follow-up period of 13.8 ± 5.7 years were enrolled. The mean age at AC was 7.5 ± 4.4 years, and 22 and 3 patients underwent AC using the ileum and colon, respectively. There were no abnormalities in serum levels of sodium, potassium, chloride, and calcium. Hypomagnesemia (magnesium <1.7 mg/dL) due to renal loss was observed in one patient (4.0%). Six (24.0%) patients had increased urinary β2-microglobulin levels and normal serum levels. The ratio of the maximum rate of tubular phosphate reabsorption to the glomerular filtration rate was low in three (12.0%) patients. Four (16.0%) patients had normal serum magnesium levels but urinary magnesium excretion <40 mg/d. Urolithiasis occurred in 11 patients (44.0%). The most common 24-hour urine metabolic abnormality was hypomagnesiuria (72.0%). No urinary metabolic parameters or daily protein intake were associated with urolithiasis.

CONCLUSION

AC for children is safe and does not significantly impact the metabolic profile. Excretions of 24-hour urinary calcium, uric acid, magnesium, and the sodium-to-potassium ratio were not associated with urolithiasis. However, a high prevalence of 24-hour urine magnesium excretion <88 mg/1.73 m 2 was noted. Further prospective studies are needed to investigate longitudinal changes in renal tubular function and 24-hour urine metabolic profiles, particularly magnesium status.

A Rocky Road: Bladder Stones in the Augmented Exstrophy-Epispadias Complex Patient

OBJECTIVE

To determine the rate of stone formation amongst patients of the exstrophy-epispadias complex with augmentation cystoplasty. We hypothesize that bowel segment choice influences the rate of stone formation after bladder augmentation and the rate of complications from bladder stone surgery.

METHODS

An IRB-approved institutional database of 1512 exstrophy-epispadias patients was reviewed retrospectively. Patients that had a history of bladder augmentation and were seen at our institution between 2003 and 2023 were included.

RESULTS

Out of 259 patients, bladder stones developed in 21.6% (56), of which the bowel segment used was colon in 147 patients and ileum in 100. Stones formed in 19% of colon augments compared to 29% ileal augments, however, this was not statistically significant (P = .07). The most common primary stone component was dahllite, followed by struvite for all augments (Table 1). The median time to stone treatment after augmentation was 4.14 years (0.75-31). Seventy-four percentage of patients had a recurrence that required a second surgery. The median time from first to second surgery and second to third surgery was 1.4 years and 2.22 years, respectively. Bladder stone surgery complications occurred in 14% of patients, vesicocutaneous fistula being the most common, and complications did not differ by augment type. Median follow-up after first stone intervention was 6.07 years (0-19.5).

CONCLUSION

The treatment of bladder stones in the exstrophy-epispadias complex remains challenging. Interventions to prevent recurrence are crucial as the majority of patients will require 2 or more stone surgeries in their lifetime.

A challenging case of a multiple large stones in enterocystoplasty: a case report

In recent years, the utilization of enterocystoplasty for bladder function enhancement has increased, albeit accompanied by risks such as stone formation, necessitating vigilant follow-up. We report a case of a 60-year-old female with a neobladder who presented with back pain, constipation, and pelvic heaviness, revealing multiple large stones in imaging. Stone analysis showed calcium oxalate and magnesium. Enterocystolithotomy was performed to manage the condition. Enterocystoplasty, a standard treatment for bladder cancer, can lead to stone formation due to factors like urinary stasis and infections. Giant stones are rare but require prompt treatment, often involving neocystolithotomy. Controlling risk factors and selecting appropriate treatment based on stone size and surgical expertise are key to improving patient outcomes.

Long-term complications and outcomes of augmentation cystoplasty in children with neurogenic bladder

Augmentation cystoplasty (AC) is an effective surgical procedure for patients with neurogenic bladder whenever conservative treatments have failed. The present study aimed to determine the risks of metabolic complications, malignancy, long-term outcomes and histopathologic changes of native bladder and the augmented intestine after AC in children with neurogenic bladder. Pediatric patients < 18 years who underwent AC between 2000 and 2020 were enrolled. Early postoperative complications, long-term outcomes and histopathologic changes in mucosal biopsies of native bladder and the augmented intestine after AC were reviewed. Twenty-two patients with a mean age of 7.6 ± 4.4 years were included. The ileum was used in 19 patients and the sigmoid colon in 3 patients. The length of hospital stay was 14.8 ± 6.8 days. Post-operatively, the urinary continence rate improved from 22.7 to 81.8% (p < 0.001). Hydronephrosis resolved in 17 of 19 patients. Vesicoureteral reflux resolved in 16 (64.0%) of the refluxing ureter units and was downgraded in 7 (28.0%). Grades of hydronephrosis and reflux significantly improved following AC (p < 0.001). The estimated glomerular filtration rate also significantly increased (p = 0.012). Formation of urinary tract stones was the most frequent late complication (in 8 patients, 36.4%). Life-threatening spontaneous bladder perforation occurred in 1 patient. After a mean follow-up of 13.4 ± 5.9 years, there were no cases of mortality, new-onset symptomatic metabolic acidosis, or changes in serum electrolytes. Of the 17 patients who were followed for > 10 years, no cases of malignancy or metaplastic changes were identified in the native bladder or augmented bowel epithelium. AC is a safe and effective procedure with low surgical and metabolic complication rates. In addition, AC provides a satisfactory continence rate and long-term protection of renal function, increases functional capacity, and regresses reflux and hydronephrosis. Individualized surveillance is recommended for the early identification of urolithiasis and metabolic disturbances.

Cystolithotripsy through appendicovesicostomy in a patient of exstrophy of bladder-episadias complex with augmented urinary bladder: A simple technique

Bladder stone formation is common in patients with augmented urinary bladder. In this case, we have applied minimally invasive technique through the existing appendicovesicostomy. After dilating the Mitrofanoff channel with dilators, we used 6.4/7.9 semirigid ureteroscope with pneumatic lithotripsy to fragment the stone. 20 Fr chest drain was introduced into the augmented bladder over the ureteroscope and all fragments were sucked out, rendering the patient stone free. Operating through the existing Mitrofanoff urinary diversion with ureteroscope along with judicious use of suction can be an excellent cost effective and minimally traumatic method of rendering the patient stone free.

Long-term outcomes of augmentation cystoplasty: A retrospective view of 54 children

INTRODUCTION AND OBJECTIVES

Throughout the years, clinicians dealing with pediatric urology disorders have resorted to bladder augmentation (BA), a demanding surgical procedure, to preserve renal functions in sundry congenital urinary tract defects. This study aimed to reveal the very long-term outcomes of BA in a large sample of pediatric patients and the role of underlying disease on renal prognosis after BA.

MATERIALS AND METHODS

A retrospective cross-sectional study was conducted on 54 children with congenital urinary defects who underwent BA. The utilized augmentation technique, the location of ureter implantation, complications, and ultrasonography findings were analyzed. Data on serum creatinine levels were collected from preoperative records and anniversaries following BA.

RESULTS

Among 54 children, 33 (61.1%) were boys. Diagnoses were spinal dysraphism (SD) (n = 13), posterior urethral valve (PUV) (n = 8), bladder exstrophy (n = 32) and trauma (n = 1). The median follow-up duration was 18 (3-31) years. The comparisons of serum creatinine levels between groups revealed that, despite no meaningful difference was present between bladder exstrophy and PUV group in the preoperative period and postoperative 1st year, cases with PUV had significantly higher levels of serum creatinine levels in the following postoperative years. Therewithal compared with the SD group, subjects with PUV had significantly higher levels at the postoperative 2nd year (P = .035) and 10th year (P = .006).

CONCLUSIONS

In our study, significantly long-term follow-up outcomes could facilitate the pre- and postoperative approach for enterocystoplasty in children. According to our results, it is noteworthy that kidney functions are at high risk of worsening in subjects with PUV and underwent BA.

Giant vesical lithiasis, complication of enterocystoplasty: case report

Frequent and recurrent pathology, bladder stone is a constant complication in enterocystoplasty enlargement. The occurrence of this lithiasis is due to some factors such as urinary tract infections, mucus secretion by the intestine segment moved, poor urinary emptying and foreign bodies (sutures, staples) intra-vesical. Clinical signs are not specific. However the formation of giant lithiases remains exceptional. Some cases have been documented in the literature. The occurrence of this affection must be prevented by dietary measures and regular follow up. New therapies for the control of mucus in the bladder tank have been emerged. Open surgical remains the most common. Today, One port trocar endoscopy enables to handle and extracted lithiases of every size.

Neuropathic Bladder and Augmentation Cystoplasty

Surgical indications for individuals with neuropathic bladder include unsafe urinary storage pressures, progressive upper tract deterioration, and continued urinary incontinence that is recalcitrant to oral pharmacologic or intradetrusor injection therapy and intermittent catheterization. Bladder augmentation is currently the gold standard surgical procedure used to increase bladder capacity and reduce storage pressures but has significant long-term risks. The medical and surgical management of neuropathic bladder, as well as long-term consequences of bladder augmentation, are reviewed.

Protean and intangible manifestation of renal stones in children

In the last decade, renal stones are being diagnosed more frequently in children across the globe. Children with renal stone often present with non-specific and subtle symptoms. Diagnosis of urolithiasis in children therefore requires a high index of suspicion especially for those living in endemic regions and with a positive family history. Additionally, management requires judicious use of radiological imaging by treating physicians.

Bladder stones after bladder augmentation are not what they seem

INTRODUCTION

Bladder and renal calculi after bladder augmentation are thought to be primarily infectious, yet few studies have reported stone composition.

OBJECTIVE

The primary aim was to assess bladder stone composition after augmentation, and renal stone composition in those with subsequent nephrolithiasis. The exploratory secondary aim was to screen for possible risk factors for developing infectious stones.

STUDY DESIGN

Patients treated for bladder stones after bladder augmentation at the present institution between 1981 and 2012 were retrospectively reviewed. Data were collected on demographics, surgeries and stone composition. Patients without stone analysis were excluded. Stones containing struvite, carbonate apatite or ammonium acid ureate were classified as infectious. The following variables were analyzed for a possible association with infectious bladder stone composition: gender, history of cloacal exstrophy, ambulatory status, nephrolithiasis, recurrent urea-splitting urinary tract infections, first vs recurrent stones, timing of presentation with a calculus, history of bladder neck procedures, catheterizable channel and vesicoureteral reflux. Fisher's exact test was used for analysis.

RESULTS

Of the 107 patients with bladder stones after bladder augmentation, 85 met inclusion criteria. Median age at augmentation was 8.0 years (follow-up 10.8 years). Forty-four patients (51.8%) recurred (14 multiple recurrences, 143 bladder stones). Renal calculi developed in 19 (22.4%) patients with a bladder stone, and 10 (52.6%) recurred (30 renal stones). Overall, 30.8% of bladder stones were non-infectious (Table). Among patients recurring after an infectious bladder stone, 30.4% recurred with a non-infectious one. Among patients recurring after a non-infectious stone, 84.6% recurred with a non-infectious one (P = 0.005). Compared with bladder stones, renal stones were more likely to be non-infectious (60.0%, P = 0.003). Of patients with recurrent renal calculi after an infectious stone, 40.0% recurred with a non-infectious one. No clinical variables were significantly associated with infectious stone composition on univariate (≥0.28) or bivariate analysis (≥0.36).

DISCUSSION

This study had several limitations: it was not possible to accurately assess adherence with bladder irrigations, and routine metabolic evaluations were not performed. The findings may not apply to patients in all clinical settings. While stone analysis was available for 3/4 of the stones, similar rates of incomplete stone analyses have been reported in other series.

CONCLUSIONS

In patients with bladder augmentation, 1/3 of bladder stones and >1/2 of renal stones were non-infectious. Furthermore, an infectious stone does not imply an infectious recurrent stone and no known clinical variables appear to be associated with stone composition, suggesting that there is a possible metabolic component in stone formation after bladder augmentation.

Neurogenic bladder in spinal cord injury patients

Neurogenic bladder dysfunction due to spinal cord injury poses a significant threat to the well-being of patients. Incontinence, renal impairment, urinary tract infection, stones, and poor quality of life are some complications of this condition. The majority of patients will require management to ensure low pressure reservoir function of the bladder, complete emptying, and dryness. Management typically begins with anticholinergic medications and clean intermittent catheterization. Patients who fail this treatment because of inefficacy or intolerability are candidates for a spectrum of more invasive procedures. Endoscopic managements to relieve the bladder outlet resistance include sphincterotomy, botulinum toxin injection, and stent insertion. In contrast, patients with incompetent sphincters are candidates for transobturator tape insertion, sling surgery, or artificial sphincter implantation. Coordinated bladder emptying is possible with neuromodulation in selected patients. Bladder augmentation, usually with an intestinal segment, and urinary diversion are the last resort. Tissue engineering is promising in experimental settings; however, its role in clinical bladder management is still evolving. In this review, we summarize the current literature pertaining to the pathology and management of neurogenic bladder dysfunction in patients with spinal cord injury.

Bladder calculi in the augmented bladder: a follow-up study of 160 children and adolescents

INTRODUCTION

Bladder augmentation (BA) has been used for various congenital and acquired conditions to create a low pressure, continent catheterizable reservoir. The prevalence of calculi within the BA have been reported to be from 3 to 52.5%. The present study reports the prevalence and risk factors of bladder calculi in patients with BA.

MATERIAL AND METHODS

A retrospective review of 160 patients was performed from January 1997 through December 2012. The various risk factors for the formation of bladder calculi such as the nature of the anatomical defect, presence of preoperative urinary calculi, type of bowel augmentation, addition of a mitrofanoff and/or bladder neck procedure, prevalence of post-operative urinary tract infections (UTIs), need for mitrofanoff revision due to stenosis/difficulty catheterization, postoperative significant hydronephrosis and bladder calculi were recorded for analysis. The children underwent open removal or endoscopic cystolithotripsy. One hundred and eight males and 52 females (average age 6.3 years) were followed up for a median of 70.5 months. All patients performed daily bladder irrigation with tap or drinking water.

RESULTS

Post-operative bladder calculi were noted in 14 (8.8%) of 160 patients following BA. Median time to stone formation was 37.5 months (11-120 months). Recurrent febrile UTIs were noted in 16 of the 160 patients following BA. The various risk factors and their outcomes are summarized in table. Eight patients underwent open cystolithotomy and four patients were treated by cystolithotripsy. Post-operative recurrent bladder calculi were noted in 2 patients. Multivariate analysis revealed that exstrophy/epispadias (OR 17.2) and recurrent UTI (OR 55.4) were independent risk factors for developing postoperative calculi in bladder augmentations. All other risk factors did not achieve statistical significance.

DISCUSSION

There seemed to be no difference in the prevalence of calculi in the ileal or colonic augmentations. Mucus secreted by the bowel segment blocks catheters leading to incomplete drainage, stagnation and UTIs. Our protocol consists of daily bladder irrigation till the effluents are clear of mucus. This is probably the key to the low prevalence of postoperative calculi (8.8%) in our patients.

CONCLUSION

Bladder exstrophy/epispadias and UTIs are independent statistically significant risk factors for the formation of bladder calculi in BA patients. Other risk factors such as preoperative calculi, bladder neck procedures and the use of mitrofanoff though not statistically significant, may contribute to the overall risk. The performance of daily bladder irrigation is an important part of our management of mucus.

Treatment of pouch stones after augmentation ileocystoplasty in children: is it always bothersome?

OBJECTIVE

To report our experience with different approaches for management of pouch stones in children with ileal-based urinary reservoir.

PATIENTS AND METHODS

Charts of children who underwent ileal-based urinary reservoirs between 2000 and 2009 were retrospectively reviewed. Patients who were diagnosed with reservoir calculi were identified; medical records were reviewed for patients' demographics, diversion details, stone criteria, mode of treatment, perioperative complications, and recurrence rate.

RESULTS

We identified 26 children with pouch stones after urinary diversion. There were 11 boys (42%) and 15 girls (58%). Mean age was 11 years (range, 4-16 years). Mean time for diagnosis was 42 months (24-120 months). Pouch stones were asymptomatic in 10 patients (38%). Fifteen cases were postbladder augmentation and 11 cases postcontinent cutaneous diversion. The mean stone size was 4 cm (range, 1-10 cm), and mean Hounsfield Unit was 585 (205-1090). Seventeen children (65%) had positive urine culture result, whereas 9 children were sterile. Seven children (27%) required open poucholithotomy, whereas 19 patients (73%) were managed endoscopically. Percutaneous approach was done in 5 children, whereas urethral access was used in 7 children. Mechanical extraction was performed in 12 cases, and stone disintegration was required in 7 cases. Eight children developed stone recurrence. Mean time for recurrence was 11 months (range, 3-19 months). Six children were after endoscopic disintegration, and all required redo endoscopic extraction. Stone analysis was available in 15 patients (struvite stones in 10 cases and calcium phosphate in 5 cases).

CONCLUSION

Pouch stones are established long-term complication of urinary diversion. Open and endoscopic approaches are valid treatment strategies.

Development of upper tract stones in patients with congenital neurogenic bladder

OBJECTIVE

Patients with neurogenic bladder are at increased risk of developing upper tract stones. We hypothesized that patients with lower urinary tract stone disease are at greater risk of developing upper tract stones.

METHODS

We performed a 10-year retrospective case-control study of patients with neurogenic bladder to determine the association between bladder and upper tract stones. Independent risk factors for upper tract stones were assessed. Cases and controls were matched 1:1. Univariable analysis was performed by Fisher's exact test and the Mann-Whitney U test. Multivariable logistic regression was performed.

RESULTS

52 cases and controls were identified. Cases were significantly more likely to be non-ambulatory, have bowel-urinary tract interposition, thoracic level dysraphism, and history of bladder stones. On multivariable analysis, independent predictors of stone formation were male sex (OR 2.82; p = 0.02), dysraphism involving the thoracic spine (OR 3.37; p = 0.014) bowel-urinary tract interposition (OR 2.611; p = 0.038), and a history of bladder stones (OR 3.57; p = 0.015).

CONCLUSION

Patients with neurogenic bladder are at increased risk for upper tract stones. The presence of bladder stones may herald the development of upper tract stones. The predictors of stone disease identified should guide prospective studies to better understand the natural history of upper tract stone development in this population.

The evolution of bladder augmentation: from creating a reservoir to reconstituting an organ

Bladder augmentation was first described in 1899. The goal at the time was to establish the ideal method to create a simple capacious reservoir for the safe storage of urine. That simple idea has over the last 100 years grown into one of the most dynamic areas in Pediatric Urology. Creative minds and hands from individuals in multiple disciplines have led us from creating a reservoir to the threshold of recreating a functional organ. In this review, we look at the historical evolution of bladder augmentation and how it exponentially grew in scope from those initial descriptions of intestinocystoplasty to the work being reported today in the field of tissue engineering.

Population based assessment of enterocystoplasty complications in adults

PURPOSE

Enterocystoplasty can be used to treat several types of bladder dysfunction. We conducted a population based study to identify the rate and significant predictors of urological surgery after adult enterocystoplasty.

MATERIALS AND METHODS

A retrospective, population based cohort was assembled using administrative data records, and adults who underwent enterocystoplasty between 1993 and 2009 were included in the analysis. Administrative data sources were used to measure primary exposure (neurogenic bladder and concurrent catheterizable channel or anti-incontinence procedure) and primary outcome (urological surgical procedures after enterocystoplasty). Multivariable Cox proportional hazards models were used (covariates of age, gender, Charlson score and socioeconomic status).

RESULTS

We identified 243 patients, of whom 61% had a neurogenic bladder, 20% had a simultaneous incontinence procedure and 18% underwent creation of a catheterizable channel. Median followup was 7.8 years (IQR 4.0-12.2). The proportion of patients who required a subsequent urological procedure was 40% (0.098 procedures per person-year of followup). A simultaneous incontinence procedure at enterocystoplasty was a significant predictor of future surgical procedures (HR 1.47, 95% CI 1.02-2.12, p = 0.0414). Cystolitholapaxy was the most common subsequent procedure (25% of patients) and a catheterizable channel conferred a significant risk of cystolitholapaxy (HR 2.92, 95% CI 1.461-5.85, p = 0.0024).

CONCLUSIONS

Repeat urological surgery is common after enterocystoplasty. Patients who require a simultaneous incontinence procedure at enterocystoplasty are more likely to require future surgery. Patients with catheterizable channels are at significant risk for future cystolitholapaxy.

Bladder augmentation: Review of the literature and recent advances

Bladder augmentation is an important tool in the management of children requiring reconstructions for urinary incontinence or preserving of the upper urinary tract in congenital malformations. We reviewed the literature and evaluated the long-term results of enterocystoplasty in the pediatric age group and summarized techniques, experimental options and future perspectives for the treatment of these patients. For this purpose, a directed Medline literature review for the assessment of enterocystoplasty was performed. Information gained from these data was reviewed and new perspectives were summarized. The ideal gastrointestinal (GI) segment for enterocystoplasty remains controversial. The use of GI segments for enterocystoplasty is associated with different short and long-term complications. The results of different centers reported in the literature concerning urological complications after enterocystoplasty are difficult to compare because of the non-comparable aspects and different items included by different authors. On the other hand, there are more and more case reports about cancer arising from bowel segments used for bladder augmentation in recent publications.

Although bladder reconstruction with GI segments can be associated with multiple complications, such as metabolic disorders, calculus formation, mucus production, enteric fistulas and potential for malignancy, enterocystoplasty is unfortunately still the gold standard. However, there is an urgent need for the development of alternative tissues for bladder augmentation.

Efficacy of bladder irrigation and surveillance program in prevention of urinary tract infections and bladder calculi in children with an ileocystoplasty and bladder neck repair

PURPOSE

In children with bladder augmentation and particularly in those with bladder neck repair (BNR), urinary tract infections (UTI) and bladder calculi are a recognised problem. Bladder irrigation potentially prevents these complications. Our aim was to investigate the efficacy of bladder irrigation supported by a surveillance program in prevention of UTI and bladder calculi in these children.

METHODS

A cohort of children subjected to ileocystoplasty with a stoma for clean intermittent self catheterisation with or without BNR was retrospectively analysed. The children were subjected to bladder irrigation and monitored by Clinical Nurse Specialists (CNS) according to a protocol. Patients' demographics, treatment methods and postoperative management were reviewed. Compliance to bladder irrigation was assessed with questionnaires. UTI recurrence and bladder calculi during follow-up were assessed.

RESULTS

28 children were included in this study. The median follow-up was 48 months (range 6-87). Compliance could be assessed in all children, except in one child (3.5%). There was no recurrent UTI reported, bladder calculi occurred in two children (7%).

CONCLUSION

Our bladder irrigation regime resulted in a low incidence of calculi by preventing recurrent UTI. The surveillance program resulted in high compliance rates in children with an augmented bladder with or without BNR.

Augmentation enterocystoplasty in overactive bladder: is there still a role?

Overactive bladder (OAB) is a highly prevalent syndrome defined as "urinary urgency, usually accompanied by frequency and nocturia with or without urgency urinary incontinence, in the absence of urinary tract infection or other obvious pathology." It is known to generate a large degree of bother and can lead to significant morbidity. Augmentation cystoplasty (AC) historically has been reserved for patients refractory to conservative management. Over time, the treatment options for OAB have grown. We now have multiple pharmacological agents approved by the US Food and Drug Administration to treat OAB. In addition, neuromodulation and botulinum toxin now are viable options for patients who have suboptimal outcomes after treatment with anticholinergics and/or pelvic floor behavioral therapy. This may suggest that AC no longer is utilized as a mainstay therapy for OAB. However, despite these many possible treatment options, AC remains an important, time-tested tool in the armamentarium of the urologist to combat the patient with refractory OAB.

Biofilm dispersal: mechanisms, clinical implications, and potential therapeutic uses

Like all sessile organisms, surface-attached communities of bacteria known as biofilms must release and disperse cells into the environment to colonize new sites. For many pathogenic bacteria, biofilm dispersal plays an important role in the transmission of bacteria from environmental reservoirs to human hosts, in horizontal and vertical cross-host transmission, and in the exacerbation and spread of infection within a host. The molecular mechanisms of bacterial biofilm dispersal are only beginning to be elucidated. Biofilm dispersal is a promising area of research that may lead to the development of novel agents that inhibit biofilm formation or promote biofilm cell detachment. Such agents may be useful for the prevention and treatment of biofilms in a variety of industrial and clinical settings. This review describes the current status of research on biofilm dispersal, with an emphasis on studies aimed to characterize dispersal mechanisms, and to identify environmental cues and inter- and intracellular signals that regulate the dispersal process. The clinical implications of biofilm dispersal and the potential therapeutic applications of some of the most recent findings will also be discussed.

Mitrofanoff continent catheterizable conduits: top down or bottom up?

OBJECTIVE

During augmentation and Mitrofanoff procedures, conduits are usually implanted into the posterior bladder wall. Anatomical considerations may necessitate an anterior conduit. To compare the relative drainage efficiency in patients with posterior and anterior conduits, we studied their rates of bladder stone formation and urinary tract infection (UTI).

MATERIALS AND METHODS

A retrospective chart review identified exstrophy patients who underwent augmentation and Mitrofanoff between 1991 and 2003. Patients with 3 years or greater follow-up were included. Fifty-four patients fit this criterion, with a conduit implanted anteriorly (33) or posteriorly (21). We compared rates of bladder stone formation and UTI. Stomal revisions and the status of the bladder neck were also noted.

RESULTS

Stone formation and UTI rates were higher in the anterior conduits, although only UTI showed a statistically significant difference. Patient demographics were similar between the two groups, including age and sex. The rates of stomal complications and the bladder neck status were also similar.

CONCLUSIONS

Patients with anterior conduits had an increased risk of UTI and bladder stone formation compared to those with posterior conduits, although this was not significant in the case of bladder stone rate. This may indicate sub-optimal bladder drainage and should be addressed with careful preoperative counseling and close follow-up.

Postoperative cystolithiasis in a case of cloacal malformation treated using an endoscopic pneumatic lithotripter through a combination of percutaneous and transurethral approaches

Long-term management of patients with cloacal malformation is still challenging to pediatric surgeons and urologists. Recently, we experienced postoperative cystolithiasis in a case of cloacal malformation. All stones were removed successfully by using an endoscopic pneumatic lithotripter through a combined approach from the cystostomy and the narrow reconstructed urethra. To the best of our knowledge, this was the first time for this combined approach to be applied in a patient with cloacal malformation. It has a particular appeal because it is simple, safe, and minimally invasive.

Chapitre A - Lithiase et vessie neurogène

Stones of the upper and lower urinary tract are frequently observed in spinal cord injury patients. In this article, the authors reviewed the literature to identify the most reliable tools for diagnosis and follow-up. A review of recently published series demonstrated an excess risk of kidney and bladder stones in this population. The authors discuss the possible measures of prevention and identification of high-risk groups likely to benefit from more intensive follow-up.

Chapitre C-2 C - Traitement de l’hyperactivité détrusorienne neurologique : entérocystoplasties

The importance of a good capacity bladder reservoir able to fill at low pressure has now been clearly established. These properties have a double advantage: they ensure urinary continence and prevent damage to the upper urinary tract. In the case of failure of the various medical treatments, including botulinum toxin injections, surgical bladder augmentation can be considered, especially in the presence of poor bladder compliance. The authors present the technical details of bladder augmentation by enterocystoplasty or by alternative techniques and their medium- and long-term results, and define the postoperative surveillance of this type of surgery.

Single percutaneous access for endoscopic extraction of lithiasis after intestinocystoplasty

PURPOSE

Bladder-stone formation is a common problem following augmentation cystoplasty. Urological management is controversial. We describe a minimally invasive technique using electrohydraulic vesicolithotripsy via a single percutaneous access.

MATERIAL AND METHODS

Between 1998 and 2004, 10 percutaneous extractions of bladder calculi were performed in seven patients with bladder augmentation. Prior bladder enlargement was performed for neuropathic bladder dysfunction in four cases and bladder exstrophy in three cases. The procedure involved percutaneous placement of a 10- or 12-mm laparoscopic trocar, after which the airtightness valve of the trocar was removed. A rigid nephroscope allowed direct visualization of calculi. Stones were fragmented with electrohydraulic lithotripsy when necessary. Removal of the fragments was by grasping forceps or basket. Vigorous, warmed-saline bladder irrigation eliminated residual fragments.

RESULTS

The technique was successful in all cases, resulting in controlled bladder-stone-free status and no surgical complications. The only complication was hypothermia linked to prolonged operation time, inadequate warmed-saline irrigation and lack of waterproof sheets.

CONCLUSIONS

Percutaneous vesicolithotripsy was highly successful and easy to perform, without being restricted by size and number of calculi. The continence mechanism of a reconstructed urethra or Mitrofanoff conduit should not be compromised. As recurrent stone formation is expected in children with augmented bladder, this technique appears to be suitable for bladder calculi removal during the long-term follow-up of multioperated patients.

Metabolic factors in the causation of urinary tract stones in patients with enterocystoplasties

Stones are a common complication of the storage of urine in intestinal reservoirs. Previous studies have identified predisposing physical characteristics in the reservoirs. Biochemical and dietary factors have been little investigated. Fifteen patients (6 males and 9 females) who had undergone various enterocystoplasty operations and who had subsequently formed either upper or lower urinary tract stones were investigated. The programme has been previously described and included stone, blood and urine analysis and dietary review. Comparison was made with 15 age- and sex-matched idiopathic stone formers with normal bladders. Stones were infective in origin in 86% of cases, and 14% were sterile. Metabolic screen showed that 80% of enterocystoplasty patients had risk factors for at least three different types of stone. All patients had raised pH (mean 6.93) and hypocitraturia. Five had a raised alkaline phosphatase. Raised serum and urinary calcium, hyperoxaluria and hyperuricosuria were found in 33% of patients. Five had a 24-h urine volume below 1.6 l/day. All patients had a high risk index (PSF) for phosphatic stones and 12 also for calcium oxalate stones. Compared to age-and sex-matched idiopathic stone-formers, the urine had a higher pH, sodium and protein excretion and a lower calcium and citrate excretion. Although the patients were already selected as stone-formers, the data show that metabolic and dietary factors are present. They may be as important in the aetiology of the stones, as the already recognised factors of infection and poor reservoir drainage. Investigation should include such factors, the presence of which may be taken into account in a prophylactic regime.

Bladder stone formation after sigmoidocolocystoplasty: statistical analysis of risk factors

PURPOSE

Bladder stone formation (BSF) after sigmoidocolocystoplasty (SCP) is a major source of morbidity. The authors identify risk factors and analyze them statistically.

METHODS

Medical records of 106 patients who had SCP at our institute were reviewed to examine the incidence of post-SCP BSF, the stone removal method and length of follow-up. The primary underlying pathological conditions were myelomeningocele in 103 patients and other conditions in 3. Risk factors for BSF were statistically assessed by comparing cases with and without BSF.

RESULTS

Bladder stone formation occurred in 20 (18.9%) of 106 patients (BSF group). The remaining 86 did not have stones (NBSF group). Mean age at SCP was 11.7 years in the BSF group and 10.2 years in the NBSF group. Mean follow-up was 12.0 years in the BSF group and 11.0 years in the NBSF group. BSF developed after a mean of 30.3 +/- 25.6 months after SCP. Twenty-two stone removal procedures were performed in the BSF group and spontaneous evacuation occurred in 4 instances. Once stone free, BSF recurred in 4 patients. Although differences between the 2 groups with respect to sex, age at SCP, follow-up period, bladder capacity, bladder compliance, incidence of gram-negative bacteriuria, incidence of gram-positive coccus bacteriuria, electrolytes, frequency of urinary catheterization, post-SCP incidence of vesicoureteric reflux, and incidence of ureteric reimplantation were not statistically significant, differences in the incidence of spontaneous micturition, bladder neck tightening procedures, or gram-positive bacillus bacteriuria, or frequency of bladder irrigation were all statistically significant (P < .05 in all, Fisher's Exact test).

CONCLUSIONS

The authors are the first to statistically analyze a wide range of varying risk factors for BSF. BSF would appear to be common after SCP.

Entérocystoplastie d'agrandissement

Augmentation enterocystoplasty refers to a technique that consists in removing a bowel segment in order to suture it onto the bladder. This technique is indicated in case of reduced bladder capacity and/or compliance, in case of failure of conservative treatments. The goal is to improve the patient's urination comfort, but above all to ensure long-term protection of the upper urinary tract. All bowel segments may be utilized but the ileum is the segment of choice. The selected digestive segment must be detubulized in order to better decrease its peristaltic contractions and obtain low-pressure urine storage. Bi-valving the bladder while preserving the detrusor usually performs augmentation enterocystoplasty. However, in case of very fibrous and thickened detrusor, a supra-trigonal cystectomy should be considered. The digestive segment is removed and detubulized, then it is sutured on to the bladder as a patch at the incision level. Following such surgery, over 90% of the patients report significantly improved quality of life. Nocturnal bladder competence is obtained in more than 90% of the patients, while 91 to 100% report diurnal bladder competence. Long-term complications may be observed, such as chronic infections with asymptomatic bacteruria (70% of the cases) not necessitating any treatment. Within the two first years, there is a 10% to 15% risk for stone formation following intestinal mucus development. Enterocystoplasty perforation may occur at a frequency estimated to range from 5 to 13%, which is a very serious and life-threatening complication. Similarly, a risk of enterocystoplasty cancer may be observed after five to ten years, in 1% of the cases.

BLADDER CALCULI AFTER AUGMENTATION CYSTOPLASTY: RISK FACTORS AND PREVENTION STRATEGIES

PURPOSE

Lower urinary tract reconstruction is an essential tool in the management of severely dysfunctional bladders in children. The incidence of calculi in augmented bladders has been reported in up to 50% of cases. We analyzed our experience with stone formation in this population to assess risk factors and outcomes.

MATERIAL AND METHODS

We performed a retrospective cohort study of all patients who underwent bladder augmentation from 1988 to 2002 at our institution. Patient demographics, risk factors and management were abstracted from the medical record.

RESULTS

A total of 105 patients (58 males and 47 females) were identified. Ileum, colon and stomach were used in 37, 18 and 50 patients, respectively. Median age was 8.0 years. Median followup was 8.4 years. A total of 12 patients (11%) were found to have bladder calculi. Ten patients with ileum (27%), 1 with colon (6%) and 1 with stomach (2%) formed stones. All patients had recurrent urinary tract infections. Nine patients were successfully treated with an endoscopic procedure. Four patients (33%) formed recurrent stones despite saline bladder irrigations. One patient had multiple recurrences but is now stone-free on a daily regimen of 20% urea instillation.

CONCLUSIONS

Augmentation cystoplasty carries an overall low risk of bladder calculi. Gastrocystoplasty had a significantly lower rate of stone formation than augmentation with ileum and colon. Urinary tract infection is an independent risk factor for stone formation. Endoscopic management is safe and effective in the majority of patients and it may be facilitated by a percutaneous access. Recurrent stones form in some patients despite aggressive medical management.

TIME TO RECURRENT STONE FORMATION IN PATIENTS WITH BLADDER OR CONTINENT RESERVOIR RECONSTRUCTION: FRAGMENTATION VERSUS INTACT EXTRACTION

PURPOSE

Stone formation following bladder or continent reservoir reconstruction in children is a major source of long-term morbidity. We determine whether the method of stone removal (fragmentation or intact extraction) affected the time to stone recurrence in children after bladder reconstruction.

MATERIALS AND METHODS

Medical records from 1993 to 2003 were examined to identify patients with urinary reconstruction subsequently treated for bladder calculi at our institution. Retrospective review of the medical records was performed to determine the type of urinary reconstruction, time to stone recurrence, method of stone removal and length of followup. Kaplan-Meier analysis was performed with each stone episode considered as an individual event. Time to recurrence was measured in months from stone removal to identification of recurrent stones.

RESULTS

A total of 60 patients with bladder or continent reservoir reconstructions had undergone 103 stone removal procedures (range 1 to 8 procedures per patient). Patients were rendered stone-free after each procedure. Stones recurred following 42.4% of intact and 43.9% of fragmented extractions at a mean of 27.0 (SD 31.3) and 27.6 (SD 21.8) months, respectively. Kaplan-Meier survival analysis curves for intact and fragmented extractions were not statistically different.

CONCLUSIONS

Time to stone recurrence in patients with bladder or continent reservoir reconstruction is not altered by the method of stone removal (fragmented versus intact extraction). Since recurrence remains a frequent problem in children after bladder augmentation and/or reconstruction, use of the least invasive modality should be the initial management recommendation.

Urolithiasis in enterocystoplasties

The incidence of stones in patients with enterocystoplasty is reported as 12-52.5%. Most patients will have multiple physical factors such as immobility, need for self catheterisation and poor urine drainage, so that it is not certain that an intestinal reservoir is the cause of stones on its own. There is little or no evidence that mucus is an aetiological factor. Foreign bodies in the reservoir, such as staples, increase the risk of stone formation from 13% to 43%. Stones require surgical removal. Minimally invasive techniques may be used for small stones. A low velocity disintegrator is required so that fragments are not propelled into the intestinal mucosa. Stones are infective in origin in 86% of cases, but 14% are sterile. Metabolic screen shows that 80% of patients have risk factors for at least three different types of stone. All patients have raised pH (mean 6.93) and hypocitraturia. Raised serum and urinary calcium, hyperoxaluria and hyperuricosuria are found in up to 33% of patients.

Augmentation cystoplasty in patients with multiple sclerosis

INTRODUCTION

Augmentation cystoplasty is an effective approach to the detrusor hyperreflexia which is refractory to conservative treatment. Sporadic data have been published in patients with progressive diseases such as multiple sclerosis (MS).

MATERIALS AND METHODS

Augmentation ileocystoplasty (Goodwin 'cup-patch') was performed in 9 patients (7 females, 2 males). The average Expanded Disability Status Scale score was 4.1 (range 3.0-6.5); 7 patients had relapse-remitting MS and 2 patients secondary-progressive MS. The indication was a detrusor hyperreflexia refractory to conservative treatment in 8 patients and a detrusor hyperrefluxia with third degree bilateral vesico-ureteral reflux and renal insufficiency in 1 patient. Pre- and postoperative objective parameters were evaluated by urodynamic examination, imaging methods and laboratory examination. Subjective evaluation was performed using a questionnaire on micturition symptoms (score 0-5) and on quality of life (score 0-6).

RESULTS

With a follow-up of 6-19 months, we recorded an average increase of the maximum detrusor capacity from 105 to 797 ml and decrease of maximum detrusor pressure from 53 to 30 cm H(2)O. Postmicturition residual urine >25% of the maximum capacity was present in 6 patients who performed clear intermittent autocatheterization postoperatively (2 patients preoperatively). In all patients there was a significant improvement in the irritation micturition symptomatology (pollakisuria, nycturia, urgency and urge incontinence) and the quality of life score improved on average from 5 to 0.7. In the case of the patient with renal insufficiency, the creatinine level decreased from 286 to 150 micromol/l; in the other patients renal function remained normal.

CONCLUSIONS

Augmentation cystoplasty is a safe and effective method for indicated patients, which significantly enhances their quality of life.

Pathological and therapeutic significance of cellular invasion by Proteus mirabilis in an enterocystoplasty infection stone model

Proteus mirabilis infection often leads to stone formation. We evaluated how bacterium-mucin adhesion, invasion, and intracellular crystal formation are related to antibiotic sensitivity and may cause frequent stone formation in enterocystoplasties. Five intestinal (Caco-2, HT29, HT29-18N2, HT29-FU, and HT29-MTX) and one ureter cell line (SV-HUC-1) were incubated in artificial urine with five Proteus mirabilis strains. Fluorescence-activated cell sorting (FACS), laser scanning microscopy, and electron microscopy evaluated cellular adhesion and/or invasion, pathologic changes to mitochondria, and P. mirabilis-mucin colocalization (MUC2 and MUC5AC). An MTT (thiazolyl blue tetrazolium bromide) assay and FACS analysis of caspase-3 evaluated the cellular response. Infected cells were incubated with antibiotics at dosages representing the expected urinary concentrations in a 10-year-old, 30-kg child to evaluate bacterial invasion and survival. All cell lines showed colocalization of P. mirabilis with human colonic mucin (i.e., MUC2) and human gastric mucin (i.e., MUC5AC). The correlation between membrane mucin expression and invasion was significant and opposite for SV-HUC-1 and HT29-MTX. Microscopically, invasion by P. mirabilis with intracellular crystal formation and mitochondrial damage was found. Double membranes surrounded bacteria in intestinal cells. Relative resistance to cotrimoxazole and augmentin was found in the presence of epithelial cells. Ciprofloxacin and gentamicin remained effective. Membrane mucin expression was correlated with relative antibiotic resistance. Cell invasion by P. mirabilis and mucin- and cell type-related distribution and response differences indicate bacterial tropism that affects crystal formation and mucosal presence. Bacterial invasion seems to have cell type-dependent mechanisms and prolong bacterial survival in antibiotic therapy, giving a new target for therapeutic optimalization of antibiotic treatment.

Pediatric urolithiasis

Urinary lithiasis in the pediatric population has evolved from a mere clinical curiosity to a disease process worthy of thoughtful and rigorous scientific study. All aspects of urinary lithiasis have undergone this evolution, including the epidemiology of stone formation in children, defining new modalities of radiologic imaging, and refining surgical techniques for stone treatment. These advancements and observations in pediatric stone disease are highlighted.