Do repeat ultrasounds affect orchiectomy rate in patients with testicular torsion treated at a pediatric institution?

INTRODUCTION

Testicular torsion is a urological emergency; as the testicular salvage rate decreases with time, prompt intervention is required to restore the blood flow. Interhospital transfers and ultrasound examinations, while clinically essential to proper treatment and diagnosis, may adversely affect outcomes by delaying surgical intervention. Patients transferred to another institution for treatment of testicular torsion may experience a further time delay by undergoing two ultrasound examinations: one at the initial admitting institution and one at the receiving institution. To the knowledge of the authors, no study has yet explored the time delays and outcomes associated with these repeat ultrasounds.

OBJECTIVE

The objective was to investigate the impact of repeat ultrasound imaging on time to treatment and patient outcomes in patients with testicular torsion.

STUDY DESIGN

A retrospective chart review of 133 patients, aged 0-20 years, treated at the authors' institution for testicular torsion was conducted. Neonate patients and patients who did not receive ultrasound were excluded. Demographic and clinical variables were collected from the electronic medical record. Pearson Chi-squared and t-tests were used for univariate comparisons, and multivariate logistic regression analysis was performed to measure the relationships between variables.

RESULTS

Forty-nine percent of patients were primary patients, and 51% were transfer patients. Fifty-two percent of transfer patients received repeat ultrasounds. In comparison to salvaged patients, those who underwent orchiectomy experienced a greater delay between presentation at the institution and surgical intervention (229 min vs 177 min, p = 0.048). The transfer status does not appear to be related to the outcome, i.e. orchiectomy versus salvage. Patients who underwent orchiectomy were more likely than salvaged patients to have received repeat ultrasounds (p = 0.008). Repeat ultrasound patients had three times the likelihood of orchiectomy of single ultrasound patients. In a subset analysis of transfer patients, repeat ultrasound patients were more likely than single ultrasound patients to receive an orchiectomy (p = 0.03).

DISCUSSION

In agreement with previous studies, patients who underwent orchiectomy were found to experience greater treatment delays and trend toward transfer. Specifically, repeat ultrasound and time between presentation and intervention appear to influence patient outcomes. The effect of repeat ultrasound on outcomes appears to be independent of the transfer status. The study was limited by its retrospective nature and small sample size.

CONCLUSION

The analysis suggests that efforts to prevent repeat ultrasounds and minimize the time between presentation and intervention would improve patient outcomes. It is proposed that standardized clinical decision-making procedures, such as the TWIST scoring system, be incorporated into hospital protocols.

Interdisciplinary pain management is beneficial for refractory orchialgia in children

INTRODUCTION

Idiopathic testicular/groin pain can be a difficult entity for children, their families, and caregivers. The role of interdisciplinary pain management has previously been demonstrated in treating chronic orchialgia at the present pediatric pain clinic.

OBJECTIVE

To evaluate the role of interdisciplinary pain management in managing refractory orchialgia. It was hypothesized that children with refractory orchialgia might respond well. Interdisciplinary care was defined as that which crosses two medical disciplines such as a surgical specialty and specialist in analgesia.

SUBJECTS AND METHODS

Pediatric patients were identified who were: ≥ 10 years old; evaluated in the pediatric urology clinic between 2002 and 2012; were diagnosed wtih ICD code 608.9 or had the diagnosis of male genital disorder NOS. Children were included if they presented with orchialgia without an identifiable cause and failed conservative management (rest, scrotal support, Sitz bath, timed voiding, constipation avoidance) including conventional anti-nociceptive analgesics (acetaminophen, non-steroidal anti-inflammatory drugs, opioids). Patient electronic medical records were reviewed retrospectively.

RESULTS

Twenty-two children met inclusion criteria. Mean age was 13.7 years (range 10-17). Nearly half (45%) of the children had chronic medical conditions such as asthma, allergies, and obesity. Twenty-one of the 22 children were referred to the pediatric pain clinic; 15 were evaluated, and one refused treatment. All children evaluated in the pediatric pain clinic were initially offered an empiric anti-neuropathic anti-convulsant (i.e. gabapentin) and/or an anti-depressant (i.e. amitriptyline) before being offered a nerve block. Of the 14 children accepting treatment in the pediatric pain clinic, six were treated solely with an empiric anti-neuropathic anti-convulsant and/or anti-depressant; eight received medications followed by nerve block (seven ilioinguinal-iliohypogastric blocks, one spinal and ilioinguinal-iliohypogastric block) (see Fig. 1). A total of eight of the 14 children (57%) treated by the pain clinic had resolution of pain, with 50% of those treated with medications alone (three out of six children) responding (two responding to gabapentin and a tricyclic antidepressant, one to gabapentin alone); and five out of eight (63%) treated with medications and then nerve block (ilioinguinal-iliohypogastric block) responding. Of the eight children undergoing nerve block, five required more than one block. The time between each block ranged from 4 to 22.6 weeks. Response to nerve block required an average of 1.4 procedures (range 1-2); mean follow-up after nerve block was 2.4 months (range 0.1-4.8).

DISCUSSION

Children with refractory orchialgia often have comorbidities that suggest a multidisciplinary approach would be useful for treating them. The present study found that the majority of children with refractory orchialgia treated in the pediatric pain clinic responded to management. Major limitations, however, included small cohort size and short follow-up, particularly in those children undergoing nerve block. There was also no objective assessment of pain improvement or improvement in quality of life, which could be rectified with a prospective study.

CONCLUSION

Collaboration and early referral for interdisciplinary pain management as one of these multidisciplinary approaches may help to coordinate care and ease patient suffering.

First Stage Approximation of the Exstrophic Bladder in Patients With Cloacal Exstrophy—Should This be the Initial Surgical Approach in all Patients?

PURPOSE

Cloacal exstrophy is rare and it represents a reconstructive challenge. Options for managing the urinary tract include primary closure or approximation of the bladder halves in the midline with later closure. We present our observations and evolving thoughts concerning optimal treatment in these patients.

MATERIALS AND METHODS

We retrospectively reviewed the records of patients with cloacal exstrophy seen in the last 5 years. Initial management was examined, including complete primary closure vs a staged approach. We noted midline defects, spinal cord abnormalities or other anatomical reasons that precluded primary closure.

RESULTS

Seven patients, including 5 females and 2 males, were identified. An omphalocele noted in all 7 patients was closed in 5 at initial operation. All underwent preservation of the hindgut in the fecal stream. Spinal cord tethering was noted in 7 of 7 cases. Complete primary bladder closure was performed in 3 of the 7 patients, while the size of the bladder plates or a large abdominal wall defect precluded closure in the remainder. Continence was not achieved in the 3 cases closed primarily. All patients achieving urinary continence underwent bladder neck closure and augmentation cystoplasty with a continent catheterizable channel.

CONCLUSIONS

Patients with cloacal exstrophy have anatomical issues that can prevent complete primary bladder closure or preclude the achievement of urinary continence. The high incidence of tethered cord places these patients at risk for upper tract changes and bladder decompensation during followup. Despite successful primary closure in 3 of 7 patients all have a tiny bladder and require secondary procedures to become continent. Extensive dissection during the first operation can contribute to more difficult dissection with potential increased morbidity during subsequent surgeries. Therefore, the best initial approach for the typical patient may be closure of the abdominal wall and approximation of the exstrophied bladder halves in the midline. Secondary closure with continent diversion and reconstruction of the external genitalia can be performed at ages 18 to 24 months.

Continent catheterizable channels and the timing of their complications

PURPOSE

We reviewed our experience with continent catheterizable channels with interest in the timing of conduit related complications.

MATERIALS AND METHODS

A retrospective review was performed of the outcome of continent catheterizable channels in all patients between 1998 and 2003 who had undergone construction of an antegrade continence enema and/or a Mitrofanoff procedure using appendix, small bowel or continent cutaneous vesicostomy. We performed a total of 117 such stomas in 37 male and 41 female patients 2.5 to 20 years old (mean age 8.9). For the antegrade continence enema we used appendix in 92% of cases, an ileal Yang-Monti tube in 6% and a cecal tube in 2%. For the continent catheterizable channel we used appendix in 43% of cases, a Yang-Monti tube in 38% and continent cutaneous vesicostomy in 19%.

RESULTS

Continence was achieved in 98% of patients. Followup was 6 to 71 months (mean 28.4). There were 27 channel related complications (23%). Stomal stenosis occurred in 7 antegrade continence enema procedures (14%) within 1 to 10 months (mean 6.2) and in 9 continent bladder channels (13%), including 5 continent cutaneous vesicostomies, within 1 to 24 months (mean 9.4) after surgery. False passages occurred in 5 antegrade continence enema procedures (10%) within 1 to 13 months (mean 3.6) and in 4 continent catheterizable channels (6%) within 1 to 13 months (mean 6.5) after surgery. Of patients with stomal stenosis 50% were treated with surgical revision, while the remainder was successfully treated with dilation. Most false passages were managed by catheter drainage alone. Reasons for revision were contained perforation, colovesical fistula and inability to catheterize. Patient noncompliance appeared to have a role in stomal stenosis.

CONCLUSIONS

Continent catheterizable stomas help patients achieve bowel and bladder continence. Stomal incontinence after reconstruction is rare. In our experience most stoma related complications occurred in the first year after reconstruction. Experience with more patients and longer followup will help determine whether such problems continue to accumulate with time or whether continent stomas function well with time, particularly after the initial period of healing.

MANAGEMENT OF THE FAILED PYELOPLASTY: A CONTEMPORARY REVIEW

PURPOSE

We reviewed our experience with open dismembered pyeloplasty, with specific focus on the presentation and management of failed pyeloplasty in the pediatric population.

MATERIALS AND METHODS

We performed a retrospective review of patients who had undergone open dismembered pyeloplasty between 1998 and 2003. All patients with less than 6 months of followup were excluded from analysis. The patients were followed postoperatively with serial ultrasounds, with renograms reserved for those patients with prolonged, persistent or worsening hydronephrosis, or recurrent symptoms during followup.

RESULTS

A total of 105 pyeloplasties were performed in 103 patients (71 males and 32 females) 1 to 204 months old (mean 60), with an overall success rate of 93.3%. Followup ranged from 6 to 69 months (mean 23). The 7 patients with treatment failure were males 1 to 204 months old (mean 125), who presented most commonly with pain within 3 to 38 months (mean 13.1) after initial surgery. Subsequent ultrasound revealed worsening hydronephrosis, and renography in these patients showed a pattern consistent with obstruction. Five patients underwent initial balloon dilation, in which 1 was successful. In addition, 1 of these patients underwent an unsuccessful antegrade laser endopyelotomy. Six patients (86%) underwent open surgery, consisting of ureterocalicostomy in 3 and reoperative dismembered pyeloplasty in 3. Dense scarring was seen in all patients, 2 patients had a redundant pelvis causing kinking and 2 patients had unrecognized crossing vessels. Overall salvage rate was 100% with continued followup of 3 to 50 months (mean 18).

CONCLUSIONS

Dismembered pyeloplasty was successful in the vast majority of patients. In our series failures occurred as late as 3 years postoperatively, although most presented within 12 months of followup. Excluding routine postoperative nuclear renography did not seem to affect our ability to identify these cases. Although anatomical features such as renal pelvic size may have a role, failure is most likely secondary to technical issues, including missed crossing vessels and dependency of the anastomosis. In this series failed pyeloplasties did not respond well to balloon dilation, likely due to scar formation. Our current practice is to manage failures by open surgery, although endoscopic management by an incision may be an option.

Is postoperative cystography necessary after ureteral reimplantation?

OBJECTIVES

To evaluate the patients in our practice to determine whether postoperative cystography was useful in monitoring the outcome after ureteroneocystostomy. Surgical repair of vesicoureteral reflux is the treatment of choice after medical therapy failure. Radiographic evaluation by ultrasonography or voiding cystourethrography (VCUG) is commonly used postoperatively to evaluate for urinary tract obstruction or persistent reflux. However, imaging modalities are not without cost, both in monetary terms and in terms of radiation exposure and trauma to the child.

METHODS

We reviewed the records of all patients who underwent ureteroneocystostomy without ureteral tapering at our institution between January 1, 1996 and December 31, 1999 for primary vesicoureteral reflux. These records were evaluated with respect to the type of surgical procedure, preoperative and postoperative clinical course, and radiographic studies performed.

RESULTS

We performed reimplantation on 267 renal units in 153 patients. The surgical technique was the Cohen cross-trigonal in 120 renal units (45%), Glenn-Anderson ureteral advancement in 92 (35%), and modified Leadbetter-Politano ureteral advancement in 55 (20%). All patients underwent imaging with ultrasonography within 6 weeks of surgery. The follow-up ranged from 4 to 42 months (average 14.2). Between 3 and 8 months postoperatively, 61 patients underwent imaging with VCUG. We identified persistent reflux in six renal units. Four of six had marked improvement in their reflux. All the patients with persistent reflux were asymptomatic, including 2 patients who were no longer receiving antibiotics. Four patients developed febrile urinary tract infections postoperatively. Three of the four underwent imaging with VCUG after treatment; all three had no evidence of reflux.

CONCLUSIONS

In our population, the addition of VCUG to the postoperative evaluation did not allow us to identify those patients at risk of febrile urinary tract infections. Patients in whom persistent reflux was identified were all asymptomatic. We continue to monitor patients with ultrasonography, but believe that VCUG often provides little benefit to these children.

Early evolution of bladder emptying after myelomeningocele closure

OBJECTIVES

To analyze bladder emptying in newborns with spina bifida after closure of the myelomeningocele defect. Manipulation of the spinal cord and nerve roots results in temporary changes in bladder function in many settings.

METHODS

We reviewed 62 consecutive newborn patients who underwent closure of a myelomeningocele defect at our institution from January 1990 to December 1997. We examined the catheterized urine volumes obtained before and after closure, radiographic and urodynamic studies, and the subsequent need for intermittent catheterization. Poor bladder emptying was defined as most catheterized urine volumes greater than 10 mL (20% of expected bladder capacity). Adequate follow-up was available for 54 patients for a period of 4 to 96 months (mean 42). One patient with posterior urethral valves was excluded from the study, leaving 53 for evaluation.

RESULTS

Of the 53 patients, 4 with high outflow resistance and dyssynergy never emptied the bladder adequately before or after closure. Of the remaining 49 patients, 6 (12%) emptied well immediately after the myelomeningocele repair. In the other 43 (88%), the bladder did not empty as well after closure. The mean volume obtained with catheterization after closure was 20 mL, significantly higher (P <0.001) than the mean volume obtained before repair (6.5 mL) or after resumption of better spontaneous emptying (4 mL). Intermittent catheterization done for poor emptying was required for an average duration of 11 days (range 2 to 42). Of the 43 patients with poor emptying immediately after closure, 32 (74%) required catheterization for 2 weeks or less; the remaining 11 (26%) required catheterization for 2 to 6 weeks. Despite the relatively early resumption of good emptying, numerous patients (19 of 49) required additional intervention (clean intermittent catheterization or vesicostomy) before attempts to toilet train.

CONCLUSIONS

A clinical pattern similar to spinal shock does occur in most newborns after closure of a myelomeningocele defect. Resumption of near-complete emptying usually occurs less than 2 weeks after repair but may require up to 6 weeks.

Angiotensin type II receptor expression and ureteral budding

PURPOSE

Deletion of the angiotensin type II receptor gene (Agtr2) in mice results in a spectrum of urinary tract anomalies similar to that in humans. The mechanism behind this anomalous development is poorly understood. We evaluated Agtr2 expression as it relates to normal and abnormal ureteral budding.

MATERIALS AND METHODS

A total of 400 wild type mice were inspected at birth for gross evidence of a urinary tract anomaly. In addition, the urinary tracts of 30 wild type embryos were evaluated at 11.0/11.5 and 13.5 weeks of gestation. These embryos were examined for ureteral budding site via section and whole mount in situ hybridization with c-ret probe and Agtr2 expression via in situ hybridization with Agtr2 riboprobe. There were 740 newborn mice homozygous for the null mutation of Agtr2 also evaluated along with 55 angiotensin type II knockout embryos at the aforementioned gestational ages.

RESULTS

All wild type newborn animals were grossly normal. Of the angiotensin type II knockout newborns 23 (3.1%) had gross abnormalities of the urinary tract at birth. The predominant finding was a duplicated collecting system associated with a hydronephrotic upper pole moiety. These duplicated collecting systems fulfilled the Meyer-Weigert law. Interestingly, 25 (59.5%) of the knockout embryos showed abnormal ureteral budding. However, in wild type embryos Agtr2 was expressed at this "ectopic" cranial site between the wolffian duct and metanephric mesenchyme.

CONCLUSIONS

Although not the sole regulator, angiotensin type II receptor expression may have a role in the embryological development of the urinary tract by inhibiting aberrant ureteral budding. A defect in this inhibitory process appears to cause ectopic ureteral budding, and may subsequently lead to renal dysplasia and other congenital anomalies of the kidney and urinary tract.

Small intestinal submucosa as a urethral coverage layer

PURPOSE

Urethrocutaneous fistula is the most common complication of hypospadias surgery. Numerous techniques have been used to decrease the incidence of this complication and the use of biocompatible materials in surgery has expanded the options in difficult situations. We hypothesized that porcine small intestinal submucosa may be used as a coverage layer after urethral surgery. We evaluated the histological changes associated with small intestinal submucosa when used as a coverage layer over the urethra in a rabbit model.

METHODS AND METHODS

We performed urethral surgery in 16 New Zealand White rabbits divided into 4 animals each in groups 1-sham operation with penile degloving only, 2-penile degloving and small intestinal submucosa patch placement, 3-urethrotomy without a patch and 4-urethrotomy with a small intestinal submucosa patch. The graft edges were marked with permanent suture at surgery for later identification. All rabbits were maintained for 6 weeks before sacrifice. The urethra of each animal was then serially sectioned and examined histologically.

RESULTS

Histological examination of animals with an small intestinal submucosa patch revealed a foreign body tissue reaction with an infiltrate of histiocytes, giant cells and lymphocytes in the area of graft placement. There was no histological evidence of remaining small intestinal submucosa patch in any sections. The urethral mucosa healed normally in all cases in which it was disrupted. There was no evidence of acute or chronic inflammation in any group 1 or 2 nonsmall intestinal submucosa animals and none in the animals with a small intestinal submucosa graft in areas other than the former graft site. There were also no urethrocutaneous fistulas in any of the 8 rabbits that underwent urethrotomy.

CONCLUSIONS

Small intestine submucosa provides an adequate coverage layer in the rabbit penis after urethrotomy. Histologically the foreign material did not alter normal healing of the urethral mucosa, although it did appear to cause an infiltration of histiocytes, giant cells and lymphocytes. Small intestinal submucosa has previously been studied as a scaffold on which tissue may be remodeled or may regenerate. Our study shows that small intestinal submucosa did not interfere with normal tissue healing in this animal model. When used as a urethral coverage layer, it appears to provide extra tissue between the urethra and skin. Small intestinal submucosa may potentially decrease the incidence of urethrocutaneous fistula after urethral surgery.

Association between maternal serum concentration of the DDT metabolite DDE and preterm and small-for-gestational-age babies at birth

BACKGROUND

DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) is highly effective against most malaria-transmitting mosquitoes and is being widely used in malaria-endemic areas. The metabolite, DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene), has been linked to preterm birth in small studies, but these findings are inconclusive. Our aim was to investigate the association between DDE exposure and preterm birth.

METHODS

Our study was based on the US Collaborative Perinatal Project (CPP). From this study we selected a subset of more than 44000 eligible children born between 1959 and 1966 and measured the DDE concentration in their mothers' serum samples stored during pregnancy. Complete data were available for 2380 children, of whom 361 were born preterm and 221 were small-for-gestational age.

FINDINGS

The median maternal DDE concentration was 25 mg/L (range 3-178)-several fold higher than current US concentrations. The adjusted odds ratios (OR) of preterm birth increased steadily with increasing concentrations of serum DDE (ORs=1, 1.5, 1.6, 2.5, 3.1; trend p<0.0001). Adjusted odds of small-for-gestational-age also increased, but less consistently (ORs=1, 1.9, 1.7, 1.6, 2.6; trend p=0.04). After excluding preterm births, the association of DDE with small-for-gestational-age remained.

INTERPRETATION

The findings strongly suggest that DDT use increases preterm births, which is a major contributor to infant mortality. If this association is causal, it should be included in any assessment of the costs and benefits of vector control with DDT.

Measurement of bisphenol A levels in human urine

We report a new approach for assessing human exposure to bisphenol A (BPA) by measuring BPA in urine after enzymatic deglucuronidation. This method involves addition of (13)C(12)-labeled BPA, enzymatic deconjugation, solid-phase extraction, and derivatization with pentafluorobenzyl bromide. The product of the derivatization is separated by gas chromatography followed by mass spectrometric detection using negative chemical ionization and selected ion monitoring. Using this analysis method, urine samples fortified with both a constant level of labeled BPA and a range of unlabeled BPA levels (0.27-10.6 ng/ml) demonstrated constant percentage recovery. In addition, a range of urine sample volumes (0.25-10.0 ml) with constant amounts of added internal standard produced a linear response (r(2)=0.99). The method limit of detection was 0.12 ng/ml. This method was validated by duplicate analyses using gas chromatography coupled to a high-resolution mass spectrometer.

Polychlorinated biphenyl serum levels in pregnant subjects with diabetes

OBJECTIVE

Polychlorinated biphenyls (PCBs) are persistent pollutants that are ubiquitous in the food chain; detectable amounts are in the blood of nearly everyone. Their effect on humans at background levels of exposure is an area of active investigation. Increased blood levels of dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin), a PCB-like compound, have recently been reported among subjects with diabetes, suggesting that PCB levels could be similarly elevated. To test this hypothesis, we examined a group of pregnant women whose serum PCB levels had been measured and whose diabetes status had been previously recorded.

RESEARCH DESIGN AND METHODS

Using stored serum from a large birth cohort study, we conducted a cross-sectional study of 2,245 pregnant women, of whom 44 had diabetes (primarily type 1) and 2,201 were control subjects.

RESULTS

The adjusted mean serum level of PCBs among the subjects with diabetes was 30% higher than in the control subjects (P = 0.0002), and the relationship of PCB level to adjusted odds of diabetes was linear.

CONCLUSIONS

The possibility exists that PCBs and diabetes are causality related; alternatively, the pharmacokinetics of PCBs could be altered among patients with diabetes. At any event, if the association is replicated in other studies, increased serum levels of PCBs in subjects with diabetes or their offspring may put them at increased risk of PCB-induced changes in thyroid metabolism or neurodevelopment.

Exposure to persistent organochlorines among Alaska Native women

OBJECTIVES

To report the levels of DDT, DDE, other chlorinated pesticides, and PCBs found in 131 Alaska Native women who had serum samples collected between 1980 and 1987 and to compare these levels to other published studies of DDE and PCB exposure among U.S. women.

STUDY DESIGN

Review of data collected during a case-control study of the relationship between organochlorine chemicals and breast cancer. Data for case and control women were pooled in this analysis because case-control differences were found to be minimal and because serum samples pre-dated cancer diagnoses by 3 to 10 years.

RESULTS

More than 99% of the women had detectable levels of p,p-DDE (mean 9.10 ng/mL or ppb). Mean total PCB level was 7.56 ppb. Levels of exposure varied by geographical location and ethnic identification, which maybe a reflection of dietary differences. Five of the organochlorines were detected in at least half of the study population. Results were recalculated using detection limits corresponding to other published studies of DDE and PCB levels in U.S. women. Alaska women had levels similar to those reported from New York women collected in the 1980s. We compared the PCB congener levels measured in Alaska Native women with levels reported in Arctic animals and found similar PCB congener profiles. The six most frequently detected contaminants in Alaska Natives were also detected in the marine mammal samples reported by Becker et al (5).

CONCLUSIONS

Our study identified widespread Alaska Native exposure to organochlorines that originated outside of the Arctic, a finding also seen in other studies. Our results provide a reference baseline for exposure levels during the 1980s, but further research is necessary to assess temporal trends in exposure among Alaska Natives. Further, the need for national and international inter-laboratory standardization for testing for persistent organochlorines to facilitate comparisons between Alaska Natives and other American populations is clearly demonstrated.

Congenital anomalies of the kidney and urinary tract--role of the loss of function mutation in the pluripotent angiotensin type 2 receptor gene

PURPOSE

Recent studies of the human genome and genetic engineering experiments in mice revealed that congenital anomalies of the kidney and urinary tract commonly seen in newborns in various anatomical forms are polygenic disease, that is a disease caused by simultaneous defects in multiple genes. We discuss some possible genetic explanations of the classic theories of the formation of congenital kidney and urinary tract anomalies.

MATERIALS AND METHODS

We reviewed classic and current theories regarding urinary tract development. Included in our review are recent results from our laboratory evaluating the genetic role of normal and abnormal urinary tract development.

RESULTS

We observed a genetic abnormality that may explain many classic anatomical theories of congenital kidney and urinary tract anomalies. One of the genes involved in urinary tract ontogenesis is the angiotensin type 2 receptor gene, which is the "other" angiotensin receptor. While the type 1 receptor mediates essentially all known actions of angiotensin, including its hypertensive effect, relatively little is known about the angiotensin type 2 receptor. Careful dissection studies in mutant mouse embryos selectively lacking the angiotensin type 2 receptor gene revealed that this gene is pleiotropic, that is its defect causes not only ectopic ureteral budding from the wolffian duct, but also disturbance in other subsequent ontogenic events that are critical for the normal growth of the kidney and urinary tract.

CONCLUSIONS

Many congenital anomalies of the kidney and urinary tract appear to share a common genetic cause. While these anomalies are caused by various genetic hits, abnormalities in the angiotensin type 2 receptor gene are often involved in this anomalous development. This review article offers a better understanding of the genetics involved in urinary tract development and ties some of the newly emerging genetic theories with classic anatomical theories.

The use of radiography, urodynamic studies and cystoscopy in the evaluation of voiding dysfunction

PURPOSE

Children with dysfunctional voiding disorder often undergo radiological, cystoscopic or urodynamic evaluation to identify an anatomical or organic cause. We determined the role of these studies in the evaluation, management and ultimate outcome of a large patient population with voiding dysfunction at a single institution.

MATERIALS AND METHODS

We retrospectively evaluated the records of 1, 153 children with dysfunctional voiding disorder treated from 1990 to 1999. A thorough history and physical examination with specific emphasis on voiding patterns were done and urinalysis was performed in all cases. Ultrasound of the urinary system and excretory urography were done in 1,050 (91%) and 24 (2%) patients, respectively, while voiding cystourethrography was performed in 672 (58%), including 564 with a history of nonfebrile urinary tract infection. Cystoscopy and a formal urodynamic study were performed in 61 (5%) and 40 (3.5%) cases, respectively.

RESULTS

Mean patient age at referral was 6 years (range 3 to 14). Of the children 74% were girls and 26% were boys. Physical examination of the abdomen, back, genitalia and neurological system was unremarkable in all cases. Ultrasound of the upper urinary system was normal in 1,018 patients (97%) and showed insignificant pyelectasis in 32 (3%). All 24 excretory urography studies were normal and voiding cystourethrography was normal in 470 of 672 cases (70%). Unilateral and bilateral low grade, and unilateral high grade reflux was present in 108, 19 and 3 patients, respectively. Urodynamic studies were performed in 40 children who did not respond to standard treatment. We noted detrusor instability in 16 patients, detrusor-sphincter dyssynergia in 6 and sensory abnormality in 3, while the study was completely normal in 10. Cystoscopy revealed normal findings in 17 cases, trabeculations in 21, inflammation in 20 and type 1 posterior urethral valves in 2.

CONCLUSIONS

The incidence of upper tract changes and positive anatomical findings in children with voiding dysfunction is too low to justify routine radiological evaluation and cystoscopy. However, in those who present with a nonfebrile urinary tract infection there remains an important role for voiding cystourethrography. We do not recommend routine urodynamics in children with voiding disorder because this study does not change therapy or influence the final outcome. Thorough history and physical examination lead to the correct diagnosis and treatment in the majority of children. A focus on correcting faulty voiding behavior with the judicious administration of antibiotics and anticholinergic therapy leads to a favorable outcome in most cases.

K-ras and p53 in pancreatic cancer: association with medical history, histopathology, and environmental exposures in a population-based study

Pancreatic cancer is a highly fatal cancer with few identified risk factors. Increased risk of pancreatic cancer in tobacco smokers and among diabetic patients is well established, and some reports have suggested associations with coffee consumption and occupational exposure to organochlorines. At present, there is little information regarding the possible association of these risk factors with the known genetic alterations found in pancreatic cancers, such as activation of the K-ras oncogene and inactivation of the p53 tumor suppressor gene. Knowledge of such relationships may help to understand the molecular pathways of pancreatic tumorigenesis. We investigated the association between these molecular defects and risk factors for pancreatic cancer in 61 newly diagnosed patients identified through an ongoing study of pancreatic cancer in the San Francisco Bay Area. Interview information was obtained regarding environmental exposures, medical history, and demographic factors. Serum levels of dichlorodiphenyltrichloroethylene (DDE) and polychlorinated biphenyls were available on a subset of 24 patients. Tumor blocks were located from local hospitals and used for K-ras mutational analysis at codon 12 and for p53 protein immunohistochemistry. The molecular analyses were facilitated through the use of laser capture microdissection, which provides a reliable method to obtain almost pure populations of tumor cells. Mutations in K-ras codon 12 were found in 46 (75%) of 61 pancreatic cancers. A prior diagnosis of diabetes was significantly associated with K-ras negative tumors (P = 0.002, Fisher's exact test). The absence of this mutation was also associated with increased serum levels of DDE, although this association was not statistically significant (P = 0.16, Wilcoxon's test). There was no difference in polychlorinated biphenyl levels between the K-ras wild-type and mutant groups. Immunohistochemical staining for p53 protein did not differ by patient characteristics or clinical history, but significant associations were found with poor glandular differentiation (P = 0.002, chi2 trend test), severe nuclear atypia (P = 0.0007, chi2 trend test), and high tumor grade (P = 0.004, chi2 trend test). Our results are suggestive of the presence of K-ras codon 12 mutation-independent tumorigenesis pathways in patients with prior diabetes and possibly in patients with higher serum levels of DDE. Our results also support a role for the p53 tumor suppressor protein in the maintenance of genomic integrity.

The urodynamic profile of myelodysplasia in childhood with spinal closure during gestation

PURPOSE

Spinal dysraphism is the most common cause of neurogenic bladder dysfunction in newborns. Urodynamic findings in these patients include uninhibited bladder contractions, bladder areflexia, decreased compliance and detrusor-sphincter dyssynergia. Early urodynamic studies are recommended for spina bifida to help identify bladder characteristics that may cause a risk of upper tract deterioration. We recently evaluated a new early type of intervention involving closure of the neural tube defect during gestation in 25 patients at our institution. We hypothesize that this procedure results in decreased exposure of the spinal cord to amniotic fluid, which may improve neurological function. To date we have evaluated 16 of the 25 patients with video urodynamics. We compared the results to those in the literature on patients with myelomeningocele and without prenatal intervention.

MATERIALS AND METHODS

We performed urodynamic testing in 16 patients with a mean age of 6.5 months, including cystometrography, fluoroscopic evaluation of filling and voiding, pelvic floor electromyography and post-void residual urine measurement. In addition, we retrospectively reviewed renal ultrasound, voiding cystourethrography, catheterization need, number of urinary tract infections and medication in these cases.

RESULTS

Uninhibited detrusor contractions and an areflexic bladder were identified in 6% and 43% of patients, respectively, while 19% had decreased compliance and 75% had leak point pressure greater than 40 cm. water. Mean bladder capacity was 40 cc and 31% of patients had much lower capacity than expected for age. Previous renal ultrasound and voiding cystourethrography showed evidence of upper tract dilatation and reflux in 2 cases, respectively. Intermittent catheterization and anticholinergic therapy were required by 1 patient each and 1 had a significant urinary tract infection.

CONCLUSIONS

Urodynamic findings in this population are comparable to those previously reported in the literature in patients with spina bifida without prenatal closure of the spinal defect. The lower incidence of urinary tract infection and reflux in our study probably represents more aggressive early urological management rather than neurological improvement. These urodynamic studies were performed early in life and future evaluation may ultimately reveal improved bladder function compared with that in others with myelodysplasia. However, at this time we recommend that patients who undergo spinal cord defect closure during gestation be evaluated and treated in the same manner as those with myelomeningocele but without fetal intervention.

Levels of seven urinary phthalate metabolites in a human reference population

Using a novel and highly selective technique, we measured monoester metabolites of seven commonly used phthalates in urine samples from a reference population of 289 adult humans. This analytical approach allowed us to directly measure the individual phthalate metabolites responsible for the animal reproductive and developmental toxicity while avoiding contamination from the ubiquitous parent compounds. The monoesters with the highest urinary levels found were monoethyl phthalate (95th percentile, 3,750 ppb, 2,610 microg/g creatinine), monobutyl phthalate (95th percentile, 294 ppb, 162 microg/g creatinine), and monobenzyl phthalate (95th percentile, 137 ppb, 92 microg/g creatinine), reflecting exposure to diethyl phthalate, dibutyl phthalate, and benzyl butyl phthalate. Women of reproductive age (20-40 years) were found to have significantly higher levels of monobutyl phthalate, a reproductive and developmental toxicant in rodents, than other age/gender groups (p < 0.005). Current scientific and regulatory attention on phthalates has focused almost exclusively on health risks from exposure to only two phthalates, di-(2-ethylhexyl) phthalate and di-isononyl phthalate. Our findings strongly suggest that health-risk assessments for phthalate exposure in humans should include diethyl, dibutyl, and benzyl butyl phthalates.

How well do patients with exstrophy actually void?

PURPOSE

Achieving continence and preserving renal function are goals in the care of patients with bladder exstrophy. The Young-Dees-Leadbetter bladder neck reconstruction should ideally provide continence and normal voiding dynamics without the need for intermittent catheterization. We review our experience with bladder neck reconstruction in this population with emphasis on voiding dynamics among those patients doing well.

MATERIALS AND METHODS

We retrospectively analyzed all patients with the exstrophy-epispadias complex seen at our institutions since 1985. We reviewed staged reconstruction in 53 patients, including 31 with classic bladder exstrophy, 4 with exstrophy variants and 18 with incontinent epispadias. Patients with additional neurogenic dysfunction were excluded from study. Subjective and objective data regarding voiding function and complications were collected.

RESULTS

Complete reconstruction for continence was performed in 38 cases, of which 11 that required bladder augmentation with bladder neck reconstruction or who had a different primary continence procedure were excluded from study. The remaining 27 patients treated with the Young-Dees-Leadbetter bladder neck reconstruction had 2 or more years of followup (mean 5.9). Dry intervals of at least 2 hours were achieved by 18 patients and all were considered by parents to void well. Despite near or total subjective continence and "good" voiding, 13 of these 18 patients (72%) have clinical problems related to emptying, which include recurrent urinary tract infections in 10, epididymitis in 2 and bladder calculi in 4. Objective urodynamic parameters confirm poor voiding in most patients.

CONCLUSIONS

Bladder neck reconstruction in patients with exstrophy can achieve continence without intermittent catheterization. In our experience patients who achieve these goals have an alarming frequency of clinical and urodynamic problems related to emptying. One must question the normalcy of the voiding pattern and price to achieve continence among patients with exstrophy.

Quantitative detection of eight phthalate metabolites in human urine using HPLC-APCI-MS/MS

Because of the ubiquity of phthalates and their potential role in increasing risk for cancer and reproductive dysfunction, the need for human exposure assessment studies is urgent. In response to this need, we developed a high-throughput, robust, sensitive, accurate, and precise assay for simultaneous measurement of trace levels of eight phthalate metabolites in human urine by HPLC-MS/MS. Human urine samples were processed using enzymatic deconjugation of the glucuronides followed by solid-phase extraction. The eluate was concentrated, and the phthalate metabolites were chromatographically resolved by reversed-phase HPLC, detected by APCI-tandem mass spectrometry, and quantified by isotope dilution. This selective analytical method permits rapid detection (7.7 min total run time) of eight urinary metabolites of the most commonly used phthalates with detection limits in the low nanagram per milliliter range. Assay precision was improved by incorporating 13C4-labeled internal standards for each of the eight analytes, as well as a conjugated internal standard to monitor deconjugation efficiency. This selective, sensitive, and rapid method will help elucidate potential associations (if any) between human exposure to phthalates and adverse health effects.

The role of hypercalciuria in a subgroup of dysfunctional voiding syndromes of childhood

PURPOSE

Idiopathic hypercalciuria is believed to be the cause of a variety of urinary tract complaints in clinical pediatrics, including urinary frequency, urgency, and/or dysuria, often associated with gross or microscopic hematuria. In children noncalculous manifestations of idiopathic hypercalciuria are reportedly more common than urolithiasis. We determine the use of the calcium-to-creatinine ratio for the evaluation of different subsets of functional voiding disorders.

MATERIALS AND METHODS

We retrospectively evaluated 288 patients with functional voiding disorders during the last 8 years. Patients presenting with isolated urinary tract infection were not included in the study. A thorough history with emphasis on voiding patterns was elicited and a routine urinalysis was performed in all patients. Patients were divided into 5 groups of 22 with total gross hematuria and dysfunctional voiding pattern, 102 with microhematuria and dysfunctional voiding pattern, 66 with isolated childhood daytime frequency, 45 with the isolated dysuria syndrome and 53 with combined childhood frequency-urgency-dysuria syndrome. The season at presentation was noted to determine a seasonal pattern. In 149 patients urine was evaluated for a spot calcium-to-creatinine ratio.

RESULTS

Mean age of the 95 (33%) males and 193 (67%) females was 6.1 years (range 2 to 14) and mean duration of symptoms was 10 months (1 week to 10 years). The incidence of idiopathic hypercalciuria was 28% in cases with gross hematuria and dysfunctional voiding, 30% with microscopic hematuria and dysfunctional voiding, 21% with pure childhood daytime frequency, 22% with pure dysuria, and 28% with frequency, urgency and dysuria. The patients were treated predominantly with behavioral therapy, correction of faulty voiding habits, anticholinergics and minor diet modification in some. Mean followup of 6.5 months (range 1 month to 10 years) was available for 153 patients (53%). Resolution of symptoms along with marked improvement in voiding habits was noted in 136 (89%) patients, moderate improvement in 10 (6.5%) and persistent symptoms with minimal improvement in 7 (4.5%). Treatment with thiazides was used in only 6 (2%) patients who had intractable symptoms and a markedly elevated urine calcium-to-creatinine ratio of whom 5 responded favorably.

CONCLUSIONS

Idiopathic hypercalciuria may have a significant role in cases of functional voiding disorders. It affects the different subsets of voiding disorders with remarkable consistency but the exact mechanism remains unknown. Although a significant number of patients with voiding dysfunction have an elevated calcium-to-creatinine ratio, the majority respond to standard behavioral therapy and pharmacotherapy in the form of anticholinergics, and treatment directed toward hypercalciuria is not required in most cases.

Y-to-I wrap: use of the distal spongiosum for hypospadias repair

PURPOSE

Rather than resecting the distal spongiosum lateral to the open urethra for hypospadias, we mobilized this tissue with the urethral plate away from the corpora cavernosa, subsequently wrapping it around various types of urethroplasty to prevent fistula formation.

MATERIALS AND METHODS

The distal spongiosum was preserved and used for coverage in 25 hypospadias repairs in 1 year. We initially applied it in this manner when the distal spongiosum persisted as a pillar of healthy erectile tissue but later when the distal tissue appeared more fibrous in nature. The wrap was used to cover various types of urethroplasty, including advancement in 6 cases, tubularization in 10, flip-flap repair in 6 and an island onlay pedicle graft in 3.

RESULTS

All patients have at least 1 year of followup. There has been no fistula formation or residual chordee. In 1 patient minor meatal retraction did not require a secondary procedure. Cosmetic results have been good.

CONCLUSIONS

A distal wrap of corpus spongiosum may be used to avoid fistula formation without causing residual or recurrent curvature. It re-creates a nearly normal urethra in some cases.

Organochlorine exposure and breast cancer survival

Recent research suggests that exposure to organochlorines, such as dieldrin that possess estrogenic properties, may increase the risk of breast cancer by promoting growth of malignant cells. Whether this potential also affects malignant cells not eradicated by treatment, and thereby survival, is unknown. To evaluate this blood samples from female participants in the Copenhagen City Heart Study, Denmark, were analyzed for organochlorines. A total of 195 breast cancer cases, who each provided two blood samples that were taken in 1976-78 and 1981-83, respectively, were included in the survival analysis. Dieldrin had a significant adverse effect on overall survival and breast cancer specific survival (RR, 2.78, 95% CI, 1. 38-5.59, P trend < 0.01; RR, 2.61, 95% CI, 0.97-7.01, P trend < 0. 01). This association was strengthened when exposure was assessed as the average serum concentration of the two measurements. These findings suggest that past exposure to estrogenic organochlorines such as dieldrin may not only affect the risk of developing breast cancer but also the survival.

[Organochlorine compounds and breast cancer--is there a connection between environmental pollution and breast cancer?]

Some organochlorine compounds may have weak oestrogenic effects and are therefore suspected of increasing the risk of breast cancer. The risk of breast cancer was assessed prospectively in relation to the serum concentration of several organochlorines. In all 240 women, who developed breast cancer between 1976 and 1993 were together with 477 breast cancer-free controls enrolled in a cohort-nested case-control study. The serum dieldrin concentration was associated with a significantly increased dose-related risk of breast cancer (Odds Ratio 2.05; 95% confidence interval 1.17-3.57; p for trend 0.01). There was no overall association between risk of breast cancer and DDT or polychlorinated biphenyls. The results support the hypothesis that exposure to oestrogenic organochlorines may increase the risk of breast cancer.

Pancreatic cancer and serum organochlorine levels

Occupational exposure to p,p'-dichlorodiphenyltrichloroethane (DDT) has been associated with increased pancreatic cancer risk. We measured organochlorine levels in serum obtained at the study enrollment from 108 pancreatic cancer cases and 82 control subjects aged 32-85 years in the San Francisco Bay Area between 1996 and 1998. Cases were identified using rapid case-ascertainment methods; controls were frequency-matched to cases on age and sex via random digit dial and random sampling of Health Care Financing Administration lists. Serum organochlorine levels were adjusted for lipid content to account for variation in the lipid concentration in serum between subjects. Median concentrations of p,p'-dichlorodiphenyldichloroethylene (DDE, 1290 versus 1030 ng/g lipid; P = 0.05), polychlorinated biphenyls (PCBs; 330 versus 220 ng/g lipid; P<0.001), and transnonachlor (54 versus 28 ng/g lipid; P = 0.03) were significantly greater among cases than controls. A significant dose-response relationship was observed for total PCBs (P for trend <0.001). Subjects in the highest tertile of PCBs (> or =360 ng/g lipid) had an odds ratio (OR) of 4.2 [95% confidence interval (CI) = 1.8-9.4] compared to the lowest tertile. The OR of 2.1 for the highest level of p,p'-DDE (95% CI = 0.9-4.7) diminished (OR = 1.1; 95% CI = 0.4-2.8) when PCBs were included in the model. Because pancreatic cancer is characterized by cachexia, the impact of this on the serum organochlorine levels in cases is difficult to predict. One plausible effect of cachexia is bioconcentration of organochlorines in the diminished lipid pool, which would lead to a bias away from the null. To explore this, a sensitivity analysis was performed assuming a 10-40% bioconcentration of organochlorines in case samples. The OR associated with PCBs remained elevated under conditions of up to 25% bioconcentration.

Mass psychogenic illness attributed to toxic exposure at a high school

BACKGROUND AND METHODS

Mass psychogenic illness may be difficult to differentiate from illness caused by bioterrorism, rapidly spreading infection, or toxic substances. We investigated symptoms attributed to exposure to toxic gas at a high school in Tennessee. In November 1998, a teacher noticed a 'gasoline-like' smell in her classroom, and soon thereafter she had a headache, nausea, shortness of breath, and dizziness. The school was evacuated, and 80 students and 19 staff members went to the emergency room at the local hospital; 38 persons were hospitalized overnight. Five days later, after the school had reopened, another 71 persons went to the emergency room. An extensive investigation was performed by several government agencies.

RESULTS

We were unable to find a medical or environmental explanation for the reported illnesses. The persons who reported symptoms on the first day came from 36 classrooms scattered throughout the school. The most frequent symptoms (in this group and the group of people who reported symptoms five days later) were headache, dizziness, nausea, and drowsiness. Blood and urine specimens showed no evidence of carbon monoxide, volatile organic compounds, pesticides, polychlorinated biphenyls, paraquat, or mercury. There was no evidence of toxic compounds in the environment. A questionnaire administered a month later showed that the reported symptoms were significantly associated with female sex, seeing another ill person, knowing that a classmate was ill, and reporting an unusual odor at the school.

CONCLUSIONS

The illness attributed to toxic exposure had features of mass psychogenic illness - notably, widespread subjective symptoms thought to be associated with environmental exposure to a toxic substance in the absence of objective evidence of an environmental cause. Alleviation of the anxiety surrounding an episode of mass psychogenic illness requires prompt recognition and a detailed investigation.

Coronal cuff: a problem site for buccal mucosal grafts

PURPOSE

Urethral reconstruction of complex hypospadias or epispadias continues to present a significant challenge. Buccal mucosa as an onlay or tube graft is an excellent option when faced with paucity of penile skin. We identified the factors that lead to success or failure in these repairs.

MATERIALS AND METHODS

During 6 years we placed 34 buccal mucosal grafts in 31 patients to repair complex hypospadias and epispadias. Penile skin was preferentially used for urethroplasty but a free buccal mucosal graft was used for reconstruction due to lack of adequate penile skin. The cases were complicated with an average of 5 previous unsuccessful repairs each in 16. Grafts ranged from 1.5 to 10 cm. and 10 patients required pieced grafts. We created 1 combination, 16 onlay and 17 full tube grafts. Buccal mucosa was used with a Thiersch-Duplay urethroplasty in 8 patients.

RESULTS

Anastomotic stricture in 5 patients was proximal in 4. Fistula was a complication in 13 grafts that generally developed on the distal shaft, particularly at the coronal cuff. Of the 7 patients who underwent proximal Thiersch-Duplay urethroplasty with a distal buccal graft 6 had a coronal fistula. Fistula was more common with tube and pieced than with onlay grafts.

CONCLUSIONS

Fistula is overwhelmingly the most common complication after buccal mucosal graft urethroplasty. Most fistulas develop at the coronal cuff, and we suspect that skin coverage and potential blood supply have not been good in that region. Anticipation of this problem during stage 1 of hypospadias repair would allow more advantageous distribution of the existing penile skin. Good distal skin coverage cannot be compromised in these complex cases.

Does every patient with prenatal hydronephrosis need voiding cystourethrography?

PURPOSE

Prenatal ultrasound has allowed early identification of urinary tract abnormalities that may require urological followup or early intervention. While all children with prenatal hydronephrosis should undergo ultrasound within the first few weeks of life, we believe that there is a subset of postnatal hydronephrosis for which voiding cystourethrography can be avoided if careful observation is continued.

MATERIALS AND METHODS

For 5 years 175 infants with a history of prenatal hydronephrosis were evaluated by ultrasound. Of 60 infants with less than Society for Fetal Urology grade II unilateral or bilateral hydronephrosis 44 underwent voiding cystourethrography as part of the early evaluation and 16 were observed without voiding cystourethrography. Four infants for whom we would routinely obtain voiding cystourethrography were excluded from study due to severe prenatal hydronephrosis, renal duplication, hydroureter, ipsilateral small or echogenic kidney and grade II or higher hydronephrosis.

RESULTS

Voiding cystourethrography was positive in 6 of the 40 infants (15%) with less than grade II hydronephrosis. Of these cases 3 had grade III or higher vesicoureteral reflux and 1 with high grade reflux required reimplantation. None of the 16 patients followed without voiding cystourethrography has required further evaluation or intervention. In all patients with negative or no voiding cystourethrography parenchyma was preserved and hydronephrosis stabilized or resolved.

CONCLUSIONS

Prenatal and postnatal ultrasound in infants should be used to guide further urological evaluation. Among infants with less than grade II hydronephrosis postnatally 15% had reflux on voiding cystourethrography, which is significantly higher than that reported among normal children (approximately 1%). However, none of the 16 infants observed without voiding cystourethrography on short-term antibiotic prophylaxis had deleterious renal events with 6 months to 4.5 years of followup. Therefore, we question the actual significance of the reflux detected in the first cohort of infants. Voiding cystourethrography can provide a definitive answer. However, we also believe that it is not absolutely mandatory based on the outcome in the observed group. With careful counseling and followup most patients with less than grade II hydronephrosis can be observed without urological sequela.

How they begin and how they end: classic and new theories for the development and deterioration of congenital anomalies of the kidney and urinary tract, CAKUT

CAKUT are problems that often require surgical intervention or, in the worst case, lead to renal failure and the need for dialysis and/or renal transplantation. It is believed that these anomalies share a common genetic cause and to date there has been no good animal model with which to study these abnormalities. Although the abnormal interaction between the ureteral bud and metanephric blastema leads to renal hypodysplasia, vesicoureteral reflux, and ectopic ureters to name a few, the genetic and biochemical modulation of urinary tract development is not understood. Studies using the mouse strain mutant for angiotensin type 2 (AT2) receptors have given new insight into this mystery. The animals show defective apoptosis of undifferentiated mesenchymal cells in the area surrounding the developing kidney and urinary tract. This abnormal apoptosis may well interfere with the normal interaction between the ureteral bud and metanephric blastema resulting in CAKUT. This abnormal interaction would theoretically lead to preexisting intrinsic abnormalities of the kidney, which are programmed and take effect early in embryonic development. In the worst cases, the renal abnormalities would lead to progressive deterioration of renal function. Undoubtedly, there are more genes and biochemical modulators involved in this process other than the RAS and AT2 receptors. Our current animal model gives new and unique possibilities with which to study development of the kidney and urinary tract and ultimately seek ways of preventing an often debilitating disease process.

Does every patient with prenatal hydronephrosis need voiding cystourethrography?

PURPOSE

Prenatal ultrasound has allowed early identification of urinary tract abnormalities that may require urological followup or early intervention. While all children with prenatal hydronephrosis should undergo ultrasound within the first few weeks of life, we believe that there is a subset of postnatal hydronephrosis for which voiding cystourethrography can be avoided if careful observation is continued.

MATERIALS AND METHODS

For 5 years 175 infants with a history of prenatal hydronephrosis were evaluated by ultrasound. Of 60 infants with less than Society for Fetal Urology grade II unilateral or bilateral hydronephrosis 44 underwent voiding cystourethrography as part of the early evaluation and 16 were observed without voiding cystourethrography. Four infants for whom we would routinely obtain voiding cystourethrography were excluded from study due to severe prenatal hydronephrosis, renal duplication, hydroureter, ipsilateral small or echogenic kidney and grade II or higher hydronephrosis.

RESULTS

Voiding cystourethrography was positive in 6 of the 40 infants (15%) with less than grade II hydronephrosis. Of these cases 3 had grade III or higher vesicoureteral reflux and 1 with high grade reflux required reimplantation. None of the 16 patients followed without voiding cystourethrography has required further evaluation or intervention. In all patients with negative or no voiding cystourethrography parenchyma was preserved and hydronephrosis stabilized or resolved.

CONCLUSIONS

Prenatal and postnatal ultrasound in infants should be used to guide further urological evaluation. Among infants with less than grade II hydronephrosis postnatally 15% had reflux on voiding cystourethrography, which is significantly higher than that reported among normal children (approximately 1%). However, none of the 16 infants observed without voiding cystourethrography on short-term antibiotic prophylaxis had deleterious renal events with 6 months to 4.5 years of followup. Therefore, we question the actual significance of the reflux detected in the first cohort of infants. Voiding cystourethrography can provide a definitive answer. However, we also believe that it is not absolutely mandatory based on the outcome in the observed group. With careful counseling and followup most patients with less than grade II hydronephrosis can be observed without urological sequela.

Serum concentrations of organochlorine compounds and the subsequent development of breast cancer

A nested case-control study was conducted to examine the association between serum concentrations of 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), the primary metabolite of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT), and polychlorinated biphenyls (PCBs) and the development of breast cancer up to 20 years later. Cases (n = 346) and controls (n = 346) were selected from cohorts of women who donated blood in 1974, 1989, or both, and were matched on age, race, menopausal status, and month and year of blood donation. Analyses were stratified by cohort participation because median DDE and PCB concentrations among the controls were 59 and 147% higher in 1974 than 1989, respectively. Median concentrations of DDE were lower among cases than controls in both time periods [11.7% lower in 1974 (P = 0.06) and 8.6% lower in 1989 (P = 0.41)]. Median concentrations of PCBs were similar among cases and controls [P = 0.21 for 1974 and P = 0.37 for 1989 (Wilcoxon signed rank test)]. The risk of developing breast cancer among women with the highest concentrations of DDE was roughly half that among women with the lowest concentrations, whether based on concentrations in 1974 [odds ratio (OR), 0.50; 95% confidence interval (CI), 0.27-0.89; P(trend) = 0.02] or in 1989 (OR, 0.53; 95% CI, 0.24-1.17; P(trend) = 0.08). The associations between circulating concentrations of PCBs and breast cancer were less pronounced but still in the same direction (1974: OR, 0.68; 95% CI, 0.36-12.9; P(trend) = 0.2; and 1989: OR, 0.73; 95% CI, 0.37-1.46; P(trend) = 0.6). Adjustment for family history of breast cancer, body mass index, age at menarche or first birth, and months of lactation did not materially alter these associations. These associations remained consistent regardless of lactation history and length of the follow-up interval, with the strongest inverse association observed among women diagnosed 16-20 years after blood drawing. Results from this prospective, community-based nested case-control study are reassuring. Even after 20 years of follow-up, exposure to relatively high concentrations of DDE or PCBs showed no evidence of contributing to an increased risk of breast cancer.

Serum concentrations of various environmental contaminants and their relationship to sex steroid concentrations and phallus size in juvenile American alligators

Recent studies have reported a number of abnormalities in the hatchling and juvenile alligators of Lake Apopka, FL (USA). These abnormalities include modifications of plasma concentrations of sex steroids in males and females as well as abnormalities in gonadal morphology, gonadal enzyme activity, and steroidogenesis. Embryonic exposure to environmental contaminants in the eggs has been hypothesized to be the causal agent for these changes. However, posthatchling exposure can also contribute to changes in reproductive and endocrine functioning. We have detected serum concentrations of 16 of 18 organochlorine pesticides or metabolites (OCs) and 23 of 28 congener-specific polychlorinated biphenyls (PCBs) examined in juvenile alligators from Lake Apopka, Orange Lake, and Lake Woodruff National Wildlife Refuge. Lake Apopka juveniles had significantly elevated serum concentrations of p,p'-DDE, dieldrin, endrin, mirex, oxychlordane, SigmaDDTs, and SigmaPCBs compared to juveniles from the other lakes. Further, we observed no correlations between serum contaminant concentrations and sex steroid concentrations (estradiol-17beta and testosterone). However, serum testosterone was significantly lower in males from Lake Apopka and Orange Lake compared to Lake Woodruff NWR. We did not observe relationships between phallus size or other body parameters and serum contaminant levels. Phallus size was smaller in males from Lake Apopka even after adjustment for body size. We suggest that the observations previously reported for juvenile alligators-and observed again in this study-are apparently not associated with the current serum levels of the environmental contaminants we measured, but could be due to exposures during embryonic development to these or other pollutants. Future studies must determine if a causal relationship exists between the contaminants found in alligator eggs and abnormalities observed in the hatchlings and persisting in juveniles.

Angiotensin type 2 receptor is important in the normal development of the ureter

In humans, the actions of angiotensin II are transduced through the AT1 and AT2 receptors which have recently been implicated in renal organogenesis. Polymorphisms in the human angiotensin II receptor genes have been linked to cardiovascular and nephrological disorders. In this study we evaluated 35 patients with either primary obstructive megaureter or posterior urethral valves. Each was genotyped for the A1166 AT1 polymorphism and the recently described A-1332G AT2 transition. The incidence of these genetic variants was also evaluated in normal controls without any ultrasonographic urological abnormalities. Similar to our previous findings in congenital urological abnormalities, the AT1 receptor genotype distribution did not differ between patients with either primary obstructive megaureter or posterior urethral valves versus controls. In contrast, compared with normal controls, there was a dramatic increase in the occurrence of the AT2 A-1332G transition in patients with primary obstructive megaureter (75.0% vs. 41.9% in controls, P<0.025). In patients with posterior urethral valves, there was no difference in the occurrence of the transition versus controls (36.9%, P=NS). Thus, there is no correlation between the AT1 receptor gene polymorphism and urological abnormalities. However there is an increased incidence in the AT2 genetic variant in patients with primary obstructive megaureter.

Serum organochlorine pesticides and PCBs and breast cancer risk: results from a prospective analysis (USA)

OBJECTIVE

To prospectively evaluate relationships of organochlorine pesticides and polychlorinated biphenyls (PCBs) with breast cancer, we conducted a case-control study nested in a cohort using the Columbia, Missouri Breast Cancer Serum Bank.

METHODS

Women donated blood in 1977-87, and during up to 9.5 years follow-up, 105 donors who met the inclusion criteria for the current study were diagnosed with breast cancer. For each case, two controls matched on age and date of blood collection were selected. Five DDT [2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane] analogs, 13 other organochlorine pesticides, and 27 PCBs were measured in serum.

RESULTS

Women in the upper three quartiles of hexachlorobenzene were at twice the risk of breast cancer compared to those in the lowest quartile. However, there was no evidence for a dose-response relationship, and the association was limited to women whose blood was collected close to the time of diagnosis. Women with higher serum levels of other organochlorine pesticides and PCBs showed no increased risk of breast cancer overall, although positive associations were suggested for PCB-118 and PCB-138 when blood was collected close to the time of diagnosis.

CONCLUSIONS

Results of this study do not support a role for organochlorine pesticides and PCBs in breast cancer etiology.

Role of the angiotensin type 2 receptor gene in congenital anomalies of the kidney and urinary tract, CAKUT, of mice and men

Angiotensin type 2 receptor gene null mutant mice display congenital anomalies of the kidney and urinary tract (CAKUT). Various features of mouse CAKUT impressively mimic human CAKUT. Studies of the human type 2 receptor (AGTR2) gene in two independent cohorts found that a significant association exists between CAKUT and a nucleotide transition within the lariat branchpoint motif of intron 1, which perturbs AGTR2 mRNA splicing efficiency. AGTR2, therefore, has a significant ontogenic role for the kidney and urinary tract system. Studies revealed that the establishment of CAKUT is preceded by delayed apoptosis of undifferentiated mesenchymal cells surrounding the urinary tract during key ontogenic events, from the ureteral budding to the expansive growth of the kidney and ureter.

Organochlorine exposure and risk of breast cancer

BACKGROUND

Some organochlorine compounds may have weak oestrogenic effects and are, therefore, suspected of increasing the risk of breast cancer. We assessed prospectively the risk of breast cancer in relation to serum concentrations of several organochlorine compounds.

METHODS

In 1976, serum samples from 7712 women were obtained from participants in the Copenhagen City Heart Study as part of physical examinations and interviews about lifestyle factors. During 17 years of follow-up, 268 women developed invasive breast cancer. Each woman with breast cancer was matched with two breast-cancer-free women from the remaining cohort. We analysed in 1996-97 the serum samples from 240 women with breast cancer and 477 controls.

FINDINGS

Dieldrin was associated with a significantly increased dose-related risk of breast cancer (adjusted odds ratio 2.05 [95% CI 1.17-3.57], p for trend 0.01). Beta-hexachlorocyclohexane increased risk slightly but not significantly (p for trend 0.24). There was no overall association between risk of breast cancer and p,p'-dichlorodiphenyltrichloroethane or metabolites or for polychlorinated biphenyls. Exclusion of women with breast cancer diagnosed within 5 years of blood sampling strengthened the result for dieldrin, but did not affect the other results.

INTERPRETATION

These findings support the hypothesis that exposure to xeno-oestrogens may increase the risk of breast cancer.

Prenatal urinary ascites and persistent cloaca: risk factors for poor drainage of urine or meconium

PURPOSE

The unique confluence of the urinary, genital and gastrointestinal tracts in girls with persistent cloaca potentially results in aberrant drainage of urine and meconium that may be characteristic, allowing a prenatal diagnosis to be made.

MATERIALS AND METHODS

Three of our last 15 patients with cloacal anomalies presented with urinary ascites due to intraperitoneal reflux through the genital system. In 3 female patients a long, narrow cloaca was associated with a high confluence of the urethra, vagina and rectum. All 3 patients ultimately underwent creation of a cutaneous vesicostomy.

RESULTS

In all 3 cases cutaneous vesicostomy effectively diverted urine away from the cloaca before definitive repair.

CONCLUSIONS

The urethra-like persistent cloaca may result in significant outflow resistance. When combined with high confluence, it may cause aberrant drainage of urine and/or meconium. When such problems are noted prenatally, they are likely to persist postnatally and require intervention.

Role of the renin-angiotensin system in disorders of the urinary tract

PURPOSE

The role of the renin-angiotensin system in the homeostasis of fluid, electrolyte and blood pressure has been known for quite some time. Recent developments indicate that angiotensin has a profound role, not only in the developing urinary tract but also in the response of the urinary tract to injury. In this review we outline these characteristics.

MATERIALS AND METHODS

We summarize the clinical approach to congenital abnormalities of the kidney and urinary tract, and report new data obtained in genetically engineered mice. Furthermore, we present the connection between the mutant mice observations and human congenital abnormalities.

RESULTS

Genetically engineered mutants clearly indicate that the renin-angiotensin system is important for normal renal and urological development. As in glomerular disease, the renin-angiotensin system is involved in progressive damage due to urological disease.

CONCLUSIONS

While the renin-angiotensin system is important for blood pressure regulation, it also affects the embryogenesis of the urinary tract and modulates renal injury due to specific disease processes. The importance of angiotensin and its blockade provides an exciting avenue for possible early treatment in children with congenital anomalies of the kidney and urinary tract.

Ureterocystoplasty: is it necessary to detubularize the distal ureter?

PURPOSE

The conventional technique for ureterocystoplasty includes complete mobilization and incision of the ureter. We describe a modified procedure in which the distal 3 cm. of ureter are left in place and intact.

MATERIALS AND METHODS

This modification has been used in our last 13 cases of ureterocystoplasty. The first 7 patients with followup of more than a year (mean 28 months) are included in this series, and 6 have undergone video urodynamic evaluation before and after reconstruction.

RESULTS

Clinical results have been good. Four patients who have been toilet trained are continent. There have been no problems from stagnant urine in the intact ureter with only 1 case of pyelonephritis and no bladder calculi. Mean bladder capacity on cystometrogram has increased from 103 to 236 ml. after reconstruction and reached 137% of expected capacity for age and size (range 110 to 155%). No uninhibited contractions or problems with compliance have been noted.

CONCLUSIONS

The distal ureter may be left intact for ureterocystoplasty to protect ureteral blood supply. This modified technique is sound from a physiological standpoint, technically easier and associated with good results.

Renal angiotensin converting enzyme promotes renal damage during ureteral obstruction

PURPOSE

We and others have shown that angiotensin II has a pivotal role in renal damage in various renal injuries. Although most angiotensin II actions are associated with the angiotensin type 1 receptor, there is increasing evidence that the angiotensin type 2 receptor also transduces some important effects of angiotensin II. In this regard we recently observed that mice with genetically engineered disruption of the angiotensin type 2 receptor, termed Agtr2 mutants, are more susceptible to structural renal damage after ureteral obstruction. Recent evidence suggests that a genetically determined increase in angiotensin converting enzyme activity in humans promotes end organ damage. Therefore, we determined whether renal damage in Agtr2 mutants is associated with heightened angiotensin converting enzyme activity.

MATERIALS AND METHODS

We studied 28 wild type and 19 Agtr2 mutant mice with unilateral ureteral obstruction. Seven days after obstruction was created serum samples were obtained to evaluate angiotensin converting enzyme activity. The obstructed and contralateral kidneys were harvested for histological analysis and determination of renal angiotensin converting enzyme activity by high pressure liquid chromatography.

RESULTS

Renal angiotensin converting enzyme was uniformly higher than serum angiotensin converting enzyme in normal wild type and Agtr2 mutant mice. However, even at baseline Agtr2 mutant mice had strikingly higher renal angiotensin converting enzyme activity than normal wild type mice (mean plus or minus standard error 1,492+/-83 versus 450+/-60 milliunits per gm. tissue weight, p <0.0005). Histological analysis revealed more extensive parenchymal damage in the obstructed kidneys of mutant mice than in identically treated controls. Notably while unilateral ureteral obstruction decreased renal angiotensin converting enzyme activity in each group, activity remained persistently higher in the Agtr2 mutants than in normal mice (mean 742+/-146 versus 310+/-43 milliunits per gm. tissue weight, p <0.005).

CONCLUSIONS

We propose that elevated renal angiotensin converting enzyme activity contributes to more severe renal parenchymal damage in ureteral obstruction by promoting the availability of growth factors, such as angiotensin II, or depleting antiproliferation factors, such as bradykinin or nitric oxide. These findings complement previous observations that angiotensin converting enzyme inhibition preserves the renal parenchyma after injury, including obstruction.

Role of angiotensin in the congenital anomalies of the kidney and urinary tract in the mouse and the human

The role of angiotensin in fluid and electrolyte and blood pressure homeostasis is well known. Recent developments indicate that angiotensin has a profound role not only in the developing urinary tract but also in the response of the urinary tract to specific noxious stimuli. Furthermore, the role of angiotensin II and its receptor has been understood quite poorly with respect to the developing renal unit. Knockout mice for the ATR2 gene show a significant incidence of congenital urinary tract anomalies. The congenital anomalies of the kidney and urinary tract (CAKUT) seen in these mice are very similar to the anomalies observed in humans. This has been supported further by the finding of an abnormality in the genetic sequence in patients with CAKUT. This article reviews experimental laboratory data as well as the potential implications for humans.

Ureterocystoplasty: is it necessary to detubularize the distal ureter?

PURPOSE

The conventional technique for ureterocystoplasty includes complete mobilization and incision of the ureter. We describe a modified procedure in which the distal 3 cm. of ureter are left in place and intact.

MATERIALS AND METHODS

This modification has been used in our last 13 cases of ureterocystoplasty. The first 7 patients with followup of more than a year (mean 28 months) are included in this series, and 6 have undergone video urodynamic evaluation before and after reconstruction.

RESULTS

Clinical results have been good. Four patients who have been toilet trained are continent. There have been no problems from stagnant urine in the intact ureter with only 1 case of pyelonephritis and no bladder calculi. Mean bladder capacity on cystometrogram has increased from 103 to 236 ml. after reconstruction and reached 137% of expected capacity for age and size (range 110 to 155%). No uninhibited contractions or problems with compliance have been noted.

CONCLUSIONS

The distal ureter may be left intact for ureterocystoplasty to protect ureteral blood supply. This modified technique is sound from a physiological standpoint, technically easier and associated with good results.

Multi-institutional study of testicular microlithiasis in childhood: a benign or premalignant condition?

PURPOSE

Testicular microlithiasis, a rare ultrasonographic diagnosis in children, has been shown to coexist in benign and malignant conditions. The natural history of incidentally discovered testicular microlithiasis has not been well defined in the pediatric population. The concern that testicular microlithiasis may be a premalignant condition has been raised. Reports indicate as much as a 45% association of germ cell tumors with testicular microlithiasis at the time of tumor diagnosis and there have been 4 cases of interval testicular tumor development associated with preexisting testicular microlithiasis. To address this issue we performed a multi-institutional study to evaluate children with incidentally diagnosed testicular microlithiasis.

MATERIALS AND METHODS

Data on 26 patients with a mean age of 12.3 years at presentation with incidentally discovered testicular microlithiasis were collected from 7 institutions. Presenting scrotal conditions were reviewed. Two children with a previous testicular malignancy were excluded from study.

RESULTS

Followup ranged from 1 month to 7 years (mean 27.6 months). Testicular biopsy and tumor marker (alpha-fetoprotein and beta-human chorionic gonadotropin) determinations were performed in 9 and 15 patients, respectively. To date no testicular tumor has developed during clinical followup.

CONCLUSIONS

Our multi-institutional study has not yet shown a trend toward the malignant degeneration of incidentally diagnosed testicular microlithiasis in children. However, we still advocate close surveillance of patients with testicular microlithiasis, such as yearly testicular ultrasound, physical examination, and judicious tumor marker determinations. We propose that a registry be started to follow prospectively patients with testicular microlithiasis to define its significance better.

Serum concentrations of organochlorine compounds and endometrial cancer risk (United States)

OBJECTIVES

Endogenous and exogenous estrogens are important in the development of endometrial cancer. Several organochlorine compounds, such as o,p'-DDT, have estrogenic properties. The objective of this case-control analysis was to examine serum concentrations of organochlorine compounds and risk of endometrial cancer.

METHODS

Analyses were based on a sample of 90 endometrial cancer cases and 90 individually matched community controls from a multicenter case-control study in five geographic regions of the United States. Information on potential confounders, including menstrual and reproductive factors, cigarette smoking, diet, and weight, was obtained by interview.

RESULTS

The adjusted relative risk of endometrial cancer in the highest quartile of exposure compared with women in the lowest quartile was 0.7 (95 percent confidence interval [CI] = 0.2-2.0) for p,p'-DDE, and 0.9 for total polychlorinated biphenyls (PCBs) (CI = 0.4-2.5).

CONCLUSIONS

These findings do not support the hypothesis that organochlorine compounds are linked to the development of endometrial cancer.

Laparoscopic evaluation for a contralateral patent processus vaginalis: part III

OBJECTIVES

Between May 1, 1992 and August 1, 1996, 759 consecutive children younger than 10 years of age were evaluated and treated for known inguinal hernia. These children were participating in a prospective investigation of the potential role of diagnostic laparoscopy in the evaluation of the contralateral inguinal anatomy. The initial two series of data (parts I and II of this three-part series) were previously presented at the 1993 and 1995 American Academy of Pediatrics meetings.

METHODS

Of 759 patients, 100 children were diagnosed with bilateral inguinal hernias and therefore did not undergo laparoscopy. Thirty-two patients did not undergo laparoscopic evaluation due to technical difficulties or complicated clinical situations. The patient's contralateral inguinal region was carefully examined under anesthesia, and predictions were made regarding the likelihood of contralateral patent processus vaginalis (CPPV). Six hundred twenty-seven children underwent diagnostic laparoscopy to confirm the presence or absence of CPPV. Laparoscopy was initially exclusively performed through the umbilicus prior to repair of the known hernia, but over the last 26 months, 250 children successfully underwent laparoscopy through the ipsilateral hernia sac.

RESULTS

Of patients younger than 1 year of age, 114 were diagnosed with both a known unilateral hernia and CPPV, whereas 132 had a unilateral hernia only (46% versus 54%). Among children older than 1 year of age, 148 (39%) were diagnosed with unilateral hernia and CPPV, and 233 (61%) were diagnosed with a unilateral hernia alone. After examination under anesthesia, 233 of the 627 patients were suspected of having a CPPV, and 107 were confirmed at laparoscopy (46%). The remaining 394 patients were not believed to have a CPPV. Normal inguinal anatomy was confirmed in 234 patients (59%), but 160 patients were found at laparoscopy to have a CPPV (41%).

CONCLUSIONS

A contralateral patent processus vaginalis may be present in a surprising number of young patients being evaluated for a known inguinal hernia. Laparoscopy can be performed without a separate incision when the ipsilateral hernia sac is of sufficient width to allow passage of the scope. Laparoscopy is the best method for evaluating the contralateral inguinal region, particularly in younger children, as it prevents unnecessary inguinal exploration and it decreases the risk that the child will later present with a clinical contralateral hernia.

Serum levels of several organochlorine pesticides in farmers correspond with dietary exposure and local use history

In response to reported increased cancer risks among farmers, the Agricultural Health Study (AHS) was designed to examine health outcomes and environmental exposures among farm families in the United States. In the pilot phase of the AHS, food, beverage, air, dermal, dust, surface wipe, and biological specimens (blood and urine) were collected and analyzed for six farm families in two states (IA and NC). In addition, questionnaires were administered to examine previous pesticide use. This paper reports the organochlorine pesticide results of the serum and dietary analyses as well as questionnaire results from the pilot exposure study of farmers and their families. Note, no organochlorine pesticides were reported as currently being applied to the study farms. In all human serum samples examined, typical U.S. population levels were found for the majority of the pesticides. In addition, human serum levels of organochlorine pesticides showed no significant daily or seasonal variation. However, serum trans-nonachlor levels were found to be higher in people living on the two farms in North Carolina than in people living on the four farms in Iowa (p < 0.05). Further, unusually high dieldrin levels were found in serum samples from a farmer and spouse living on an Iowa farm, and these levels were significantly higher than those of people living on the other farms (p < 0.05). Dieldrin was persistent in the foods consumed on the same Iowa farm where family members showed elevated serum levels. In addition, dietary samples from the North Carolina farms exhibited high levels of chlordane. No organochlorine pesticides were found in any of the drinking water samples. Dietary dieldrin levels on the same Iowa farm exceeded the oral reference dose (RfD) eight- to eleven-fold (50 ng/kg-day). No other pesticide exceeded the RfD. However, dietary chlordane levels at a North Carolina farm reached 17% of the RfD. Previous use of aldrin on an Iowa farm corresponded to dieldrin found in the diet and in the serum of the farmer and spouse. Previous reported use of chlordane on the North Carolina farms corresponded with measurable dietary levels of chlordance and higher serum trans-nonachlor levels than the levels in Iowa farm families.