Impact of body mass index on 30-day postoperative morbidity in pediatric and adolescent patients undergoing continent urinary tract reconstruction.

INTRODUCTION: Obesity has been thought to increase the risk of complications and need for additional resources with surgery, but only a limited amount of evidence is available in the pediatric population. OBJECTIVE: The objectives were to describe the weight status of pediatric and adolescent patients undergoing a continent urinary tract reconstruction and to determine the association between obesity and 30-day postoperative morbidity. STUDY DESIGN: A retrospective cohort study was performed for pediatric and adolescent patients aged up to 20 years who underwent a continent urinary tract reconstruction between January 2010 and November 2016. Weight status was stratified by the body mass index (BMI) for age z-scores as follows: underweight (<5th percentile), normal (5th to <85th percentiles), overweight (85th to <95th percentiles), and obese (≥95th percentile). Primary outcomes included the duration of intensive care and hospitalization as well as re-admissions and complications within 30 days. RESULTS: A total of 182 continent reconstructions were identified during the study period. Demographic and peri-operative data are provided in the Table. Weight status was not associated with any primary outcomes on univariate or multivariate analysis. There was also no association in an analysis between the non-overweight or non-obese group (BMI for age z-score <85th) and overweight or obese group (BMI for age z-score ≥85th percentiles); a subgroup analysis between patients with and without myelomeningocele; or a subgroup analysis for wound, infectious, or high-grade (Clavien-Dindo grades III or higher) complications. DISCUSSION: Obesity has been consistently associated with an increased risk of surgical site infections and wound complications after a wide variety of surgeries in adults. The results from the present study conflict with those of the few available studies in the pediatric population. The high-risk nature of the present cohort may have mitigated any effect of obesity on 30-day postoperative morbidity. The limitations of the present study include its retrospective design at a single center and the potential misclassification of weight status with the BMI. CONCLUSIONS: Almost 30% of pediatric and adolescent patients undergoing a continent urinary tract reconstruction were overweight or obese. Obesity as determined by the BMI was not associated with 30-day postoperative morbidity.

Preoperative nutritional status and use of total parenteral nutrition in pediatric and adolescent patients undergoing continent urinary tract reconstruction.

INTRODUCTION: A nutritional assessment is a critical but often neglected aspect of a preoperative evaluation. Malnutrition is clearly associated with worse surgical outcomes in adults undergoing major abdominal surgery, whereas a paucity of evidence is available in the pediatric population. OBJECTIVE: The objectives were to describe the preoperative nutritional status of pediatric and adolescent patients undergoing continent urinary tract reconstruction and to determine the association among malnutrition, use of total parenteral nutrition (TPN), and surgical outcomes. STUDY DESIGN: A retrospective cohort study was performed for patients aged up to 20 years who underwent continent urinary tract reconstruction between January 2012 and November 2016. Malnutrition was classified with body mass index and height for age z-scores on admission as well as change in z-scores and weight over the 3-6 months before surgery. Primary outcomes included the duration of intensive care and hospitalization as well as readmissions and complications within 30 days. RESULTS: A total of 123 patients who underwent 130 continent urinary tract reconstructions were identified during the study period. Demographic and perioperative data are provided in the Table. Anthropometric and biochemical measurements as well as the early initiation of TPN (≤2 days) were not associated with any primary outcomes. In a subgroup analysis of patients with a bowel anastomosis, the early initiation of TPN was an independent predictor for duration of hospitalization (P < 0.0001) and 30-day complications (odds ratio 9.51, P = 0.005) after adjusting for other statistically significant and clinically relevant variables. DISCUSSION: The few available studies on surgical nutrition have primarily focused on infants and young children undergoing cardiac surgery and provided no consensus on a preoperative nutritional assessment. The findings on TPN from the present study favorably compare with a growing body of evidence in adult and pediatric critically ill and surgical patients. The limitations of the present study include its retrospective design at a single institution, potential misclassification of nutritional status, and selection bias from the initiation of TPN at the discretion of the primary surgeon. CONCLUSIONS: Malnutrition was identified in greater than 20% of pediatric and adolescent patients undergoing continent urinary tract reconstruction. Anthropometric and biochemical parameters were not associated with surgical outcomes, although the early initiation of TPN did not offer any benefit for nutritional support. In a subset of patients with a bowel anastomosis, TPN was associated with worse surgical outcomes, including a longer duration of hospitalization and development of 30-day complications.

Clinical and urodynamic outcomes in children with anorectal malformation subtype of recto-bladder neck fistula.

INTRODUCTION: Patients with anorectal malformations (ARMs) have a high incidence of genitourinary anomalies. Those with a recto-bladder neck fistula may represent a high-risk group, but their long-term urologic outcomes are poorly described. OBJECTIVE: To evaluate the clinical and urodynamic outcomes in a large cohort of patients with an ARM subtype of recto-bladder neck fistula. MATERIALS AND METHODS: A retrospective cohort study was performed of patients who had been treated for a recto-bladder neck fistula at the present institution since 2007. The primary outcomes were the ability to achieve urinary continence after 4 years of age, and development of a mildly decreased glomerular filtration rate (GFR) or worse (<89 ml/min/1.73 m2). Continence was defined as the ability to store urine for 3-4 h during the day and 8 h overnight without leakage. RESULTS: Demographic and clinical data are provided in the Summary Table. The most recent urodynamic findings included the presence of detrusor overactivity in 30 (75%) patients, median leak point pressure of 56.0 cmH2O (range, 14-140), median functional cystometric capacity at 40 cmH2O of 125.5% age-expected capacity (range, 36-473%), and median maximum cystometric capacity of 131.0% age-expected capacity (range, 44-473%). A mildly decreased GFR or worse developed in 13 (24%) patients. Of the 52 (78%) patients who were followed by pediatric urology at the present institution with a median follow-up of 30.9 months (range, 0.0-86.8), 35 (67%) were at least 4 years of age and could be assessed for continence. Continence was achieved in five (14%) patients voiding spontaneously and 15 (43%) performing CIC. Recurrent urinary tract infections (UTI) (OR 0.70, P = 0.006) were an independent predictor of incontinence, while urethral anomalies (OR 1.40, P = 0.03) were an independent predictor of chronic kidney disease (CKD) on multiple logistic regression analysis. DISCUSSION: The findings favorably compared with other studies, but were more robust due to the size of the cohort and breadth of urologic evaluation. Limitations included the retrospective design at a single institution. Incomplete clinical data and misclassification of continence may have lead to bias. CONCLUSIONS: This large cohort of patients with an ARM subtype of recto-bladder neck fistula had a high incidence of genitourinary anomalies. They were rarely able to achieve continence with spontaneous voiding alone and were at risk of developing CKD, both of which were likely multifocal in origin. Long-term urologic follow-up is warranted for patients with a recto-bladder neck fistula.

Triamcinolone injection for treatment of Mitrofanoff stomal stenosis: Optimizing results and reducing cost of care.

INTRODUCTION: Stomal stenosis is the most common complication after the creation of a continent catheterizable channel (CCC), but is challenging to treat. OBJECTIVE: To describe early experience with triamcinolone injection for the treatment of stomal stenosis. MATERIALS AND METHODS: A retrospective review was performed of patients who had undergone a triamcinolone injection (40 mg/ml) for the treatment of stomal stenosis at the present institution. The primary outcome of success was defined as a patient-reported or caregiver-reported return to ease with catheterization, and avoidance of stomal revision or indwelling catheter. The cost of care with various techniques for the treatment of stomal stenosis was also assessed by representing the cost as a percentage of charges for a re-operative Monti ileovesicostomy. RESULTS: A total of 22 injections were performed in 18 CCCs of 17 patients. Demographic and clinical data are provided in the Summary Table. Thirteen CCCs (72%) were successfully treated with a single injection. Three patients (10%) required a total of five repeat injections at a median of 5.1 months between injections (IQR, 4.6-12.4). One patient required a stomal revision at 34.9 months after the initial injection, while one patient also required a Chait cecostomy catheter. The median length of time for ease with catheterization was 11.6 months (IQR, 3.5-18.0) after the initial injection, and 10.4 months (IQR, 4.5-16.0) after any injection. No adverse effects or complications occurred from the injection. There were no variables associated with failure after the initial or any injection on univariate analysis. Represented as a percentage of charges for a reoperative Monti ileovesicostomy, the cost of care was 11.3% for a stomal revision, 5.8% for triamcinolone injection in the operating room, and 0.3% as an office-based procedure. DISCUSSION: The success rate for triamcinolone injection favorably compared with other options for the treatment of stomal stenosis. It surpassed the reported success rate of stomal dilation and approached that of stomal revision. Other studies have similarly observed a minimal risk of adverse effects and complications from both topical and intralesional corticosteroids. The limitations of the present study included its retrospective design at a single institution. A larger cohort of patients with a longer follow-up is necessary to determine its long-term durability. CONCLUSIONS: Triamcinolone injection was an effective and well-tolerated option for the treatment of stomal stenosis in any cutaneous stoma, thereby avoiding the need for a more invasive and costly stomal revision.

Botulinum toxin injection in the pediatric population with medically refractory neuropathic bladder.

INTRODUCTION: Botulinum toxin injection (BTI) has been advocated as a second line therapy in management of neuropathic bladder in pediatric population for refractory patients to conventional medical management such as anticholinergics. The purpose was to review the safety and efficacy of BTI in children with neuropathic bladder refractory to conservative non-surgical measures. We hypothesized that BTI would be an effective alternative to bladder augmentation in certain patients but not all. METHODS: We retrospectively identified 22 patients with neuropathic bladder due to any condition who underwent urologic BTI at our hospital since 2010. Multiple clinicopathologic variables were examined including the following: demographics, use of anticholinergics, the presence of anticholinergic refractoriness or intolerance, dosage of BTI, urodynamic variables, and continence status. RESULTS: The mean patient age at time of BTI was 10 years with a follow up of 12 months. Indications for BTI were anti-cholinergic refractory (AR) urodynamic parameters and/or incontinence and anticholinergic intolerance (AI). Nearly all patients received 300 Units at BTI into detrusor. No complications occurred from BTI. Overall 54% had improved continence after the initial BTI whereas 45% had achieved complete continence between catheterizations. Cystometric capacity increased by 46% and maximum detrusor pressure decreased by 43% following initial BTI (See Table). 75% of AI patients were continent between CIC after BTI compared to 50% of AR patients (P = 0.002). The observed mean duration of clinical improvement after initial BTI was 4.6 months and four patients underwent repeat BTI. Pre BTI % of age expected bladder capacity Post BTI % of age expected bladder capacity % Improvement in Urodynamic Parameter P value Cystometric Capacity (mL) 227 60 331 87 46 0.008 Maximum Detrusor Pressure (cm H2O) 63 44 43 0.002 Compliance (mL/cm H2O) 4.3 8.8 104 0.001. DISCUSSION: Our results are comparable to existing literature with respect to urodynamic parameters. The observed differences may be due to heterogenous patient population of various etiologies of neuropathic bladder and no uniform criteria to proceed with bladder augmentation. The AR patients in our cohort may have had a higher degree of bladder fibrosis which BTI would be less likely to impact and explain the differences in clinical response between AR and AI patients. CONCLUSIONS: BTI is a safe and effective treatment option for pediatric patients with neuropathic bladder refractory to standard therapy. The degree of continence observed after BTI in our series was higher for AI rather than AR patients.

Infant robotic pyeloplasty: comparison with an open cohort.

OBJECTIVE: To present our experience with infant pyeloplasty, comparing outcomes between robotic-assisted laparoscopic pyeloplasty (RALP) and open pyeloplasty (OP). MATERIALS AND METHODS: A retrospective review was performed of all children <1 year of age who underwent unilateral dismembered pyeloplasty at a single pediatric institution since January 2007. Patients with standard laparoscopic pyeloplasty were excluded. Patient demographics, intraoperative details, narcotic usage, and complications were reviewed. RESULTS: A total of 70 infants (51 boys and 19 girls) were identified, with nine RALP and 61 OP performed. Median age was 9.2 months (range, 3.7-11.9 months) for RALP and 4.1 months (range, 1.0-11.6 months) for OP (p = 0.005). Median weight was 8 kg (range, 5.8-10.9 kg) for RALP and 7 kg (range, 4-14 kg) for OP (p = 0.163). Median operative time was 115 min (range, 95-205 min) for RALP and 166 min (range, 79-300 min) for OP (p = 0.028). Median hospital stay was 1 day (range, 1-2 days) for RALP and 3 days (range, 1-7 days) for OP (p < 0.001). Median postoperative narcotic use of morphine equivalent was <0.01 mg/kg/day (range, 0-0.1 mg/kg/day) for RALP and 0.05 mg/kg/day (range, 0-2.2 mg/kg/day) for OP (p < 0.001). Median follow-up was 10 months (range, 7.2-17.8 months) for RALP and 43.6 months (3.4-73.8 months) for OP (p < 0.001). The success rate was 100% for RALP and 98% for OP. CONCLUSIONS: Infant RALP was observed to be feasible and efficacious with shorter operative time, hospital stay, and narcotic utilization than OP.

Genitourinary emergencies in children.

The aim of this paper was to to provide the primary care practitioner with a review of genitourinary conditions in children requiring emergent urological referral. These conditions include the acute scrotum/testicular torsion, scrotal masses, penile abnormalities, urinary retention and bladder outlet obstruction, abdominal masses, acute urinary stones, urinary trauma, genital abnormalities, complex anomalies and acute abdomen in patients with previous continent reconstruction. The authors discussed the presenting signs and symptoms, proper initial diagnostic work-up and the usual therapeutic course of management after evaluation by the pediatric urologist.

Pediatric urolithiasis.

Pediatric stone disease is a frequently underestimated entity that can present unique problems in its management. The condition stems from any of a number of underlying, causative factors, and the significant possibility of recurrence must always be borne in mind. The primary care physician should be aware that the condition is readily treatable by an experienced pediatric urologist who has a range of treatment modalities at his or her disposal; however, overall success is governed by a timely referral and subsequent long-term follow-up to ensure the maintenance of a stone-free state.

Magnetic resonance imaging of the dysplastic renal moiety and ectopic ureter.

PURPOSE: We determined the role of magnetic resonance imaging (MRI) in symptomatic children with clinically suspected and radiologically occult dysplastic renal moieties and ectopic ureters. MATERIALS AND METHODS: We reviewed clinical, imaging, cystoscopic, surgical and histological findings in 6 symptomatic children 1 to 15 years old with dysplastic renal moieties. RESULTS: After multiple conventional imaging studies failed to delineate urinary tract anatomy MRI provided detailed multiplanar images of dysplastic renal moieties that were diagnostic and predictive of subsequent intraoperative findings. Dysplastic upper pole moieties identified in 4 children were associated with ectopic ureters inserting into the vagina, prostatic urethra, bladder neck and bladder neck ureterocele in each. A solitary kidney with contralateral blind-ending ectopic ureters inserted into the bladder base in 2 cases. Pelvic cystic structures visualized by ultrasound in 3 patients were tortuous distal ureters on MRI. MRI specifically identified ureteral insertion sites that were not evident in 3 of the 5 patients who underwent cystoscopy. CONCLUSIONS: MRI may facilitate diagnosis, guide cystoscopy and aid in preoperative planning in children with poorly functioning renal moieties and ectopic ureters.

Modified technique of antegrade continence enema using a stapling device.

PURPOSE: We present a stapling technique for constructing an antegrade continence enema (ACE) conduit that is helpful in cases of insufficient appendiceal luminal length or when a concomitant appendiceal Mitrofanoff stoma is required. MATERIALS AND METHODS: In 6 patients with a mean age of 9.5 years who required an ACE procedure the cecum was tubularized in continuation with the orthotopic appendix at its base, using a stapling device to construct an ACE conduit. The tubularized segment was imbricated with permanent suture material. In 3 cases appendiceal length after tubularization was sufficient to allow splitting for the concomitant creation of an appendiceal Mitrofanoff stoma. RESULTS: Patients have been followed an average of 16.5 months. Stomal continence was achieved in all cases as well as reliable catheterization of the appendiceal cecostomy in 6 and the Mitrofanoff conduit in 3. CONCLUSIONS: This modification of the ACE procedure with cecal tubularization in continuation with the appendix using a stapling device is an excellent approach in cases of inadequate appendiceal length. It successfully creates a catheterizable stoma with a reliable flap valve continence mechanism. The complex reconstructive procedure is simplified by eliminating the need to use tapered small intestine, while allowing the creation of a concomitant appendiceal Mitrofanoff stoma as necessary.

Mathieu hypospadias repair: experience in 202 patients.

PURPOSE: The complication rate after Mathieu hypospadias repair was recently reported to be 3.6% in unstented cases. We reviewed our experience and results of the Mathieu repair performed at our institution during the last 5 years. MATERIALS AND METHODS: We performed 197 primary and 5 secondary repairs in 202 patients. Reconstruction of the neourethra was done with a 2-layer anastomosis using optical magnification. Urethral stents were placed for postoperative drainage in all but 1 patient. Followup was up to 54 months. RESULTS: There were no incidences of stent migration or symptomatic urinary tract infection while the stent was in place and all patients voided spontaneously after stent removal. Excellent cosmetic results were obtained in 201 cases. In 1 patient meatal retraction required subsequent meatoplasty with meatal advancement. In 2 patients pinpoint urethrocutaneous fistulas were successfully repaired. The total rate of reoperation was 1.5% in our series. There was no report of urethral stricture during followup. CONCLUSIONS: The well established Mathieu repair provides excellent cosmetic and functional results. The overall complication rate is minimal and compares favorably with stentless repair. A 2-layer neourethral anastomosis performed under sufficient optical magnification produces a watertight closure with minimal risk of fistula formation. Postoperative urethral stenting decreases this risk even further, while adding only minimal morbidity. We believe that in the era of newly reported techniques the well established Mathieu procedure should be the standard by which distal repair is judged.

Unusual anatomic presentation of ectopic ureteroceles.

The authors describe four patients with unusual anatomic presentation of ectopic ureteroceles and their surgical treatment. Over a 3-year period, four cases of unusual ectopic ureteroceles were encountered. A 6-month-old girl had a complex cloacal anomaly with an ectopic ureterocele within the cloaca. A 10-year-old boy had two large diverticuli within an ectopic ureterocele combined with a blind-ending ipsilateral ureter. A 3-year-old girl had an ectopic ureterocele combined with a periureteral diverticulum and a completely duplicated ipsilateral kidney. A 4-year-old girl was found to have a vaginal ectopic ureterocele. Despite thorough radiological investigation in all patients, a correct assessment of the anatomic defect was achieved only by surgical exploration or endoscopic evaluation. If preoperative radiological evaluation is equivocal, a high index of suspicion and intraoperative recognition of an unusual anatomic presentation of the ectopic ureterocele are essential for appropriate management and a successful outcome.

Voiding dysfunction after bilateral extravesical detrusorrhaphy.

PURPOSE: Extravesical detrusorrhaphy has been successful for correcting unilateral vesicoureteral reflux, although its use in bilateral ureteral reimplantation has been questioned because of a reportedly high incidence of significant postoperative voiding dysfunction. We reviewed the incidence of voiding dysfunction after bilateral extravesical detrusorrhaphy during the last 5 years. MATERIALS AND METHODS: From 1990 to 1995, 123 patients with a mean age of 5.8 years (231 refluxing renal units) underwent bilateral extravesical detrusorrhaphy. Patients requiring anticholinergic therapy or intermittent catheterization at surgery were excluded from study, although in 6 who were included voiding dysfunction had previously resolved. RESULTS: Grades I and II vesicoureteral reflux persisted in 1 and 3 renal units, respectively, representing a 98.3% success rate. There was no postoperative upper urinary tract obstruction. Postoperatively voiding dysfunction developed in 8 patients (6.5%), including 2 with a history of voiding dysfunction. In 3 cases (2.5%) irritative voiding symptoms controlled with oxybutynin chloride resolved 2, 4 and 24 months postoperatively, respectively. In 5 patients (4%) temporary incomplete bladder emptying and/or urinary retention required outpatient Foley catheter drainage or intermittent catheterization for 2 to 21 days. CONCLUSIONS: Bilateral extravesical detrusorrhaphy is a highly successful procedure with a low incidence of significant voiding dysfunction. Should this condition develop, in our experience it is transient and of minimal morbidity. We found an increased rate of postoperative voiding dysfunction in younger patients as well as in those with a history of resolved voiding dysfunction.

Incidence of contralateral vesicoureteral reflux following unilateral extravesical detrusorrhaphy (ureteroneocystostomy).

PURPOSE: The development of contralateral vesicoureteral reflux following different types of unilateral antireflux surgery has been reported to be as high as 22%. We review our recent experience with unilateral extravesical detrusorrhaphy in regard to the incidence of postoperative contralateral vesicoureteral reflux. MATERIALS AND METHODS: Between 1990 and 1995, 72 children underwent unilateral extravesical detrusorrhaphy. Of 73 refluxing renal moieties (1 patient had reflux in both moieties of a completely duplicated kidney) reflux grade was II in 35 (48%), III in 25 (34%), IV in 11 (15%) and V in 2 (3%). Common sheath reimplantation for complete ipsilateral duplication was performed in 16 patients. RESULTS: One patient had grade I postoperative ipsilateral vesicoureteral reflux resulting in a success rate of 98.6%. In 4 patients (5.6%) contralateral vesicoureteral reflux developed, and was grade II in 3 and grade I in 1. In all patients contralateral reflux resolved at 16, 17, 18 and 31 months of followup. No additional surgery was required in any patient. There was no association between the incidence of contralateral vesicoureteral reflux, and patient age, gender, preoperative ipsilateral reflux grade and presence of ipsilateral duplication. CONCLUSIONS: Unilateral extravesical detrusorrhaphy is a highly successful procedure with a low incidence of postoperative contralateral vesicoureteral reflux. Should reflux develop, it is of low grade with a significant rate of spontaneous resolution.

Inguinal microsurgical varicocelectomy in the adolescent: technique and preliminary results.

PURPOSE: In large series of adults microsurgical varicocelectomy has been associated with extremely high success rates, combined with minimal incidence of postoperative hydrocele. We report our initial experience of inguinal varicocelectomy using an intraoperative microscope in adolescents. MATERIALS AND METHODS: From 1994 to 1996, 32 adolescents (mean age 15.3 years) underwent inguinal microsurgical varicocelectomy. An operative microscope and Doppler probe were used during spermatic cord dissection to identify and preserve the testicular artery and lymphatics. RESULTS: All patients were available for followup, which ranged from 2 to 35 months (mean 20). There were no intraoperative complications. A temporary reactive hydrocele, which subsequently completely resolved, was observed in 1 patient. There were no palpable recurrent varicoceles. CONCLUSIONS: The operative microscope permits reliable identification of the testicular artery and lymphatics, as well as venous channels in adolescents. As a result, the postoperative development of hydrocele or recurrence of the varicocele may be prevented.

Role of the antegrade continence enema in the management of the most debilitating childhood recto-urogenital anomalies.

PURPOSE: We evaluated the antegrade continence enema for managing the most severely compromised fecal continence mechanisms and the efficacy of nonappendiceal conduits in children when appendix is unavailable. MATERIALS AND METHODS: Ten patients 3 to 25 years old underwent continent cecostomy for the purpose of the antegrade continence enema. Diagnoses included the VATER association in 4 cases, myelomeningocele in 3, cloacal anomaly in 2 and isolated imperforate anus in 1. Eight patients received a tubularized ileal conduit, 2 received an appendiceal conduit and 2 underwent concomitant fecal undiversion. RESULTS: Followup ranged from 4 to 28 months (mean 17.6). All patients have achieved excellent fecal continence and no significant stomal soilage or difficulty with catheterization has been noted. Patients reported a high degree of satisfaction. CONCLUSIONS: Continent cecostomy for the antegrade continence enema is highly effective even in the presence of severe structural anorectal disease. The tapered ileal conduit is an excellent alternative to the appendiceal conduit.

The importance of accurate diagnosis and early close followup in patients with suspected multicystic dysplastic kidney.

PURPOSE: Conservative management of children who have unequivocal multicystic dysplastic kidney with a stable or regressive pattern of disease during close followup is well established. However, a clear diagnosis may prove difficult. We report 3 cases in which the diagnosis was particularly difficult to increase awareness of the importance of applying strict criteria for the diagnosis of multicystic dysplastic kidney. MATERIALS AND METHODS: Three children in whom a diagnosis of multicystic dysplastic kidney was suspected underwent surgical exploration. One patient who did not comply with followup presented with a large retroperitoneal mass suspicious for neuroblastoma 8 months later. In another patient a growing renal cystic mass was suspicious for a multilocular cyst at 3 months of followup. At 2 months of followup a cystic nephroma was suspected in the remaining patient. RESULTS: All patients underwent surgical exploration. The patient with suspected neuroblastoma had extensive stage 3 Wilms tumor. In the child with a suspected multilocular cyst segmental multicystic dysplastic kidney of the lower pole of an ipsilateral duplicated system was found. In the patient in whom cystic nephroma was suspected mesoblastic nephroma was confirmed by the National Wilms Tumor Study Pathology Center. CONCLUSIONS: An unequivocal diagnosis of multicystic dysplastic kidney should be made early in life. The urologist should have an active role in making the initial radiological diagnosis and close followup with renal ultrasound every 3 to 4 months is essential during year 1 of life. Surgical exploration is indicated if the diagnosis becomes equivocal at any point or should concerns exist regarding compliance with followup.