The Application, Challenges, and Advancement Toward Regulatory Acceptance of Digital Toxicologic Pathology: Results of the 7th ESTP International Expert Workshop (September 20-21, 2019)

With advancements in whole slide imaging technology and improved understanding of the features of pathologist workstations required for digital slide evaluation, many institutions are investigating broad digital pathology adoption. The benefits of digital pathology evaluation include remote access to study or diagnostic case materials and integration of analysis and reporting tools. Diagnosis based on whole slide images is established in human medical pathology, and the use of digital pathology in toxicologic pathology is increasing. However, there has not been broad adoption in toxicologic pathology, particularly in the context of regulatory studies, due to lack of precedence. To address this topic, as well as practical aspects, the European Society of Toxicologic Pathology coordinated an expert international workshop to assess current applications and challenges and outline a set of minimal requirements needed to gain future regulatory acceptance for the use of digital toxicologic pathology workflows in research and development, so that toxicologic pathologists can benefit from digital slide technology.

Outcome of fetuses with lower urinary tract obstruction and normal amniotic fluid volume in second trimester of pregnancy

OBJECTIVE

Congenital lower urinary tract obstruction (LUTO) is a rare condition with high perinatal mortality and morbidity when associated with severe oligohydramnios or anhydramnios in the second trimester of pregnancy. Severe pulmonary hypoplasia and end-stage renal disease are the underlying causes of poor neonatal outcome in these cases. However, little is known about the subset of fetal LUTO that is associated with a normal volume of amniotic fluid at midgestation. The objective of the current study was to describe the natural history, underlying causes, survival and postnatal renal function outcomes in pregnancies with fetal LUTO and normal amniotic fluid volume during the second trimester of pregnancy.

METHODS

This was a retrospective study of all pregnancies with fetal LUTO and normal amniotic fluid volume in the second trimester that received prenatal and postnatal care at our quaternary care institution between 2013 and 2017. Data on demographic characteristics, fetal interventions, perinatal survival, need for neonatal respiratory support, postnatal renal function and need for dialysis at the age of 1 and 24 months were analyzed.

RESULTS

Of the 18 fetuses that met the study criteria, 17 (94.4%) survived the perinatal period. Eleven (61.1%) pregnancies developed oligohydramnios in the third trimester, six of which were eligible for and underwent fetal intervention with vesicoamniotic shunt placement, which was performed successfully in all six cases. Two (11.1%) neonates required respiratory support owing to pulmonary hypoplasia. At the age of 2 years, 14 children had follow-up information available, two (14.3%) of whom had normal renal function, eight (57.1%) had developed some degree of chronic kidney disease (Stage 1-4) and four (28.6%) had developed end-stage renal disease (ESRD), including two who had already manifested ESRD in the neonatal period.

CONCLUSIONS

Most fetuses diagnosed prenatally with LUTO that is associated with a normal volume of amniotic fluid at midgestation will have a favorable outcome in terms of perinatal survival and few will need long-term respiratory support. However, these children are still at increased risk for chronic renal disease, ESRD and need for renal replacement therapy. Larger multicenter studies are needed to characterize the prenatal factors associated with postnatal renal function, and to investigate the role of fetal intervention in the group of fetuses that present with late-onset oligohydramnios and evidence of preserved fetal renal function. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Do pediatricians routinely perform genitourinary examinations during well-child visits? A review from a large tertiary pediatric hospital

BACKGROUND

The male genital examination is a common source of discomfort for the patient and medical provider. Performance of male genital examination is imperative; however, as many treatable diagnoses can be made. Undescended testicles (UDTs), hernias, testicular tumors, and urethral abnormalities are all potentially concerning findings which can be discovered on routine examination.

OBJECTIVE

The objectives of this study are to determine the rate at which general pediatricians perform routine genitourinary (GU) examinations in the pediatric population and to determine the rate at which UDT are diagnosed or documented in the patient's history. The authors hypothesize the rate of pediatric GU examination during routine well-child visits to be in line with the previously reported rates in the adult literature.

STUDY DESIGN

Nine hundred ninety-six consecutive male well-child visits conducted by general pediatricians at the study institution were reviewed. These visits were evaluated for documentation of a detailed GU examination as well as the presence of UDT from these examinations. In addition, past medical and surgical histories were reviewed to determine if a diagnosis of UDT was noted.

RESULTS

Pediatricians at the study institution documented GU examinations 99.1% of the time during male well-child visits. Only 1.1% of the cohort had a documentation of UDT at any time point. Of the 11 patients with UDT, 6 boys (54.5%) had spontaneous descent with no referral to urology, whereas 5 (45.5%) required orchidopexy.

DISCUSSION

Prior reports suggest 70-75% of routine office visits include a genital examination. None of these reports reviewed the pediatric population, thus making this review novel in this respect. In addition, the results are vastly different from these prior studies as the authors demonstrated over 99% of male well-child examinations included documentation of a thorough genital examination. A limitation of the study is its retrospective nature, which creates a lack of standardization across the data set. In addition, without being physically present in the examination room, one cannot discern whether an examination is simply being documented without actual performance because of the template format of the electronic medical record (EMR). Furthermore, the study was not designed to best evaluate the true rate of UDTs; therefore, the reported rate of 1.1% cannot be accurately associated with a particular age at diagnosis.

CONCLUSIONS

Pediatricians do, in fact, document GU examinations on a routine basis. This finding cannot be taken with complete certainty as verification of actual examination performance is impractical. While the data demonstrated a lower than expected rate of UDT, depending upon age at diagnosis, this could indicate that although examinations are being documented, their accuracy may be diminished because of various factors at play in the healthcare system as a whole, including improper exam performance and EMR templates. Follow-up studies are required to verify these potentially changing rates of UDT and to determine if there is discordance between documentation and performance of GU examinations.

The changing gender landscape of pediatric urology fellowship: results from a survey of fellows and recent graduates

INTRODUCTION

Women are entering the subspecialty of pediatric urology at an accelerated rate. Gender differences affecting fellowship and job selection have been identified in other fields of medicine.

OBJECTIVE

The objective of this study was to understand gender differences in pediatric urology fellowship and job selection and how they may affect the workforce.

STUDY DESIGN

A 47-question electronic survey consisting of questions regarding demographics, residency training, and factors influencing fellowship and job selection was distributed to current fellows and recent graduates in pediatric urology in May 2017.

RESULTS

A total of 111 recent and current fellows were contacted, and 72% completed the survey (55% female [F] and 45% male [M]; 61% current fellows and 39% recent fellows). Respondents rated factors important in choosing pediatric urology on a scale of 1-5 (1, not important and 5, extremely important), and the top three for both genders were 1-working with children, 2-influential mentors, and 3-bread and butter cases such as inguinal orchiopexy. During residency, 93% of respondents reported having influential mentors in pediatric urology. However, mentorship was more important in fellowship choice for males than females (3.6 F, 4.1 M; P-value = 0.048), and 45% reported having only male mentors. Rating factors important in job choice on a scale of 1-5, respondents reported the top factors as 1-rapport with partners/mentorship (4.5), 2-geography/family preferences (4.3), and 3-participation in mentoring/teaching (3.8). Although most job selection criteria were rated similarly between genders, females rated call schedule higher than males (3.5 F, 2.9 M, P-value = 0.009). Although most females and males (79% of F, 78% of M, P-value = 0.868) sought primarily academic positions, a smaller proportion of females accepted academic positions (52% of F, 72% of M, P-value 0.26), and females reported lower satisfaction regarding the availability of jobs on a scale of 1-5 (1, very dissatisfied and 5, very satisfied; 3.1 F, 3.7 M; P-value = 0.034), particularly in academic positions (3.1 F, 3.7 M; P-value = 0.06). This difference was more pronounced in current fellows than recent graduates and may represent a worsening trend.

CONCLUSION

Although significant gender differences in fellowship and job selection may exist in other fields, we found that women and men choose pediatric urology fellowships and jobs using similar criteria, which include work-life balance. Gender differences exist in the influence of mentors, indicating a need for more female mentors. While men and women sought similar types of jobs, women were less satisfied with the availability of jobs, particularly academic jobs, than men, which warrants further investigation.

Birth prevalence of hypospadias and hypospadias risk factors in newborn males in the United States from 1997 to 2012

BACKGROUND

Hypospadias is a common genitourinary malformation and there are conflicting data on whether its prevalence is increasing. Previous studies have described associations with risk factors including small for gestational age (SGA), multiple gestation birth, environmental influences, and maternal factors.

OBJECTIVE

The objective of this study was to examine birth prevalence of hypospadias and hypospadias risk factors in a large national dataset and to evaluate for changes from 1997 to 2012. We hypothesized that any increase in the birth prevalence of hypospadias would be associated with an increase in risk factors such as SGA, prematurity, or multiple gestation birth.

STUDY DESIGN

The Kids' Inpatient Database was used to generate national estimates for prevalence of males born with hypospadias, SGA, prematurity, or to a multiple gestation and then prevalences were evaluated for association with time. Multivariable logistic regression was used to evaluate whether birth prevalence of hypospadias was associated with increasing year, SGA, prematurity, and multiple gestation birth.

RESULTS

The estimated birth prevalence of hypospadias increased from 6.1 per 1000 births (95% confidence interval [CI] 5.9 to 6.3) to 6.8 per 1000 births (95% CI 6.7 to 7.0), an 11.5% increase from 1997-2012 (P = 0.014). Among male births, the prevalence of SGA increased 74%, multiple gestation increased 25%, and prematurity increased 20% (P < 0.001 for all) (Summary Figure). A risk factor was seen in around 20% of males born with hypospadias. Hypospadias birth prevalence also increased in males without risk factors but was not statistically significant (9.1% increase, P = 0.5). On multivariable logistic regression, being born SGA (odds ratio [OR] = 3.3), to a multiple gestation (OR = 1.1), or premature (OR 1.9) were associated with increased odds of hypospadias (P < 0.01 for all), whereas increasing year was not (P = 0.3).

CONCLUSIONS

The estimated birth prevalence of hypospadias in the United States increased from 6.1 to 6.8 per 1000 births from 1997 to 2012. Known hypospadias risk factors of SGA birth, multiple gestation birth, and premature birth also increased over this time to a higher degree. About 20% of males born with hypospadias had one of these risk factors. The birth prevalence of hypospadias in males without any studied risk factors also increased, but this was not statistically significant. More studies are needed to evaluate whether this increase in hypospadias prevalence is due to increases in known hypospadias risk factors, new environmental exposures, improved diagnosis at birth, some combination, or unrelated causes.

Imaging characteristics associated with failure of nonoperative management in high-grade pediatric blunt renal trauma

INTRODUCTION

Some children who sustain high-grade blunt renal injury may require operative intervention. In the present study, it was hypothesized that there are computed tomography (CT) characteristics that can identify which of these children are most likely to need operative intervention.

MATERIALS AND METHODS

A retrospective review was performed of all pediatric blunt renal trauma patients at a single level-I trauma center from 1990 to 2015. Inclusion criteria were: children with American Association for the Surgery of Trauma (AAST) Grade-IV or V renal injuries, aged ≤18 years, and having available CT images with delayed cuts. The CTs were regraded according to the revised AAST grading system proposed by Buckley and McAninch in 2011. Radiographic characteristics of renal injury were correlated with the primary outcome of any operative intervention: ureteral stent, angiography, nephrectomy/renorrhaphy, and percutaneous nephrostomy/drain.

RESULTS

One patient had a Grade-V injury and 26 patients had Grade-IV injuries. Nine patients (33.3%) underwent operative interventions. Patients in the operative intervention cohort were more likely to manifest a collecting system filling defect (P = 0.040) (Fig. A) and lacked ureteral opacification (P = 0.010). The CT characteristics, including percentage of devascularized parenchyma, medial contrast extravasation, intravascular contrast extravasation, perirenal hematoma distance and laceration location, were not statistically significant. Of the 21 patients who had a collecting system injury, eight (38.1%) needed ureteral stents. Renorrhaphy was necessary for one patient. Although the first operative intervention occurred at a median of hospital day 1 (range 0.5-2.5), additional operative interventions occurred from day 4-16. Thus, it is prudent to closely follow-up these patients for the first month after injury. Two patients with complex renal injuries had an accessory renal artery resulting in well-perfused upper and lower pole fragments, and were managed nonoperatively without readmission (Fig. B).

CONCLUSIONS

Collecting system defects and lack of ureteral opacification were significantly associated with failure of nonoperative management. A multicenter trial is needed to confirm these findings and whether nonsignificant CT findings are associated with operative intervention. In the month after renal injury, these patients should be mindful of any changes in symptoms, and maintain a low index of suspicion for an emergency room visit. For the physician, close follow-up and appropriate counseling of these high-risk patients is advised.

Fetal lower urinary tract obstruction: proposal for standardized multidisciplinary prenatal management based on disease severity

OBJECTIVE

To present a single center experience of a standardized prenatal multidisciplinary management protocol for fetal lower urinary tract obstruction (LUTO) and to propose a classification of fetal LUTO based on disease severity.

METHODS

This was a retrospective cohort study of 25 consecutive fetal patients with prenatal diagnosis of primary LUTO. Fetal intervention was offered after evaluation by a multidisciplinary team. Analyses were conducted using Bayesian methodology to determine predictors of survival at 6 months postpartum. Odds ratios (ORs) with 95% credibility intervals are reported.

RESULTS

Fifteen (60.0%) of the 25 patients referred for assessment survived to postnatal evaluation. Fetal vesicoamniotic shunt was placed in 14 (56.0%) patients with 12 survivors. Multivariable analysis suggested that fetal intervention (OR, 6.97 (0.88-70.16), Pr(OR > 1) = 96.7%), anhydramnios (OR, 0.12 (0.04-0.35), Pr(OR < 1) = 99.9%), favorable fetal urine analysis (OR, 3.98 (0.63-25.15), Pr(OR > 1) = 92.7%) and absence of renal cortical cysts (OR, 3.9 (0.66-24.2), Pr(OR > 1) = 93.3%) were predictors of survival.

CONCLUSIONS

Fetal intervention and fetal renal function were independently associated with postnatal survival of fetuses with LUTO. A classification based on the severity of disease is proposed. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Urological fistulas after fetal cystoscopic laser ablation of posterior urethral valves: surgical technical aspects

OBJECTIVE

To describe the surgical technical aspects associated with the development of urological fistulas after fetal antegrade cystoscopic laser fulguration of the posterior urethral valves (PUV).

METHODS

The perioperative data for all fetal cystoscopies performed between January 2004 and August 2013 at three institutions in the USA, France and Brazil were reviewed, with particular emphasis on surgical technical aspects of the procedure and the complications encountered.

RESULTS

A total of 40 fetal cystoscopies were performed at the three institutions. Laser fulguration of the PUV was performed in 23 of these cases, with a survival rate of 60.9% (14/23) and normal renal function in 85.7% (12/14) of these infants. Urological fistulas were diagnosed postnatally in four (10%) newborns. The presence of fistulas was associated with a higher gestational age at diagnosis of PUV (P < 0.01) and with the use of semi-curved rather than curved sheaths (P < 0.01), the use of a diode laser (P < 0.01) and the use of higher laser power and energy (P < 0.01 and P < 0.01, respectively), as well as with less operator experience (P < 0.01) and with absence of fetal anesthesia/immobilization (P = 0.02).

CONCLUSION

Urological fistulas are a severe complication of fetal cystoscopic laser fulguration of PUV and are associated with type, energy and power settings of the laser and instrumentation. The use of appropriate technique and proper training of the operator are necessary to perform this fetal intervention safely.

A panel of urinary biomarkers to monitor reversibility of renal injury and a serum marker with improved potential to assess renal function

The Predictive Safety Testing Consortium's first regulatory submission to qualify kidney safety biomarkers revealed two deficiencies. To address the need for biomarkers that monitor recovery from agent-induced renal damage, we scored changes in the levels of urinary biomarkers in rats during recovery from renal injury induced by exposure to carbapenem A or gentamicin. All biomarkers responded to histologic tubular toxicities to varied degrees and with different kinetics. After a recovery period, all biomarkers returned to levels approaching those observed in uninjured animals. We next addressed the need for a serum biomarker that reflects general kidney function regardless of the exact site of renal injury. Our assay for serum cystatin C is more sensitive and specific than serum creatinine (SCr) or blood urea nitrogen (BUN) in monitoring generalized renal function after exposure of rats to eight nephrotoxicants and two hepatotoxicants. This sensitive serum biomarker will enable testing of renal function in animal studies that do not involve urine collection.

Urinary clusterin, cystatin C, beta2-microglobulin and total protein as markers to detect drug-induced kidney injury

Earlier and more reliable detection of drug-induced kidney injury would improve clinical care and help to streamline drug-development. As the current standards to monitor renal function, such as blood urea nitrogen (BUN) or serum creatinine (SCr), are late indicators of kidney injury, we conducted ten nonclinical studies to rigorously assess the potential of four previously described nephrotoxicity markers to detect drug-induced kidney and liver injury. Whereas urinary clusterin outperformed BUN and SCr for detecting proximal tubular injury, urinary total protein, cystatin C and beta2-microglobulin showed a better diagnostic performance than BUN and SCr for detecting glomerular injury. Gene and protein expression analysis, in-situ hybridization and immunohistochemistry provide mechanistic evidence to support the use of these four markers for detecting kidney injury to guide regulatory decision making in drug development. The recognition of the qualification of these biomarkers by the EMEA and FDA will significantly enhance renal safety monitoring.

Design and evaluation of immunotoxicity studies

The evaluation of potential adverse effects of pharmaceuticals on the immune system is part of the standard drug development procedures and needs to be available prior to the start of phase III clinical trials. Although the histopathological assessment of lymphoid organs/tissues is considered fundamental for the identification and characterization of immunotoxic reactions, additional investigations are now recommended by the European guidelines for repeated-dose toxicity testing of medicinal products in order to achieve an accurate assessment of immune system functionality with regard to immunomodulation. In the present paper, we describe and discuss a study design which permits the investigation of the immune function in a 4-week study in rats following immunization by subcutaneous administration of the T-dependent antigen Keyhole Limpet Hemocynin (KLH). This includes assessment of hematology parameters, titration of KLH-specific antibodies in serum, lymphocyte immunophenotyping in blood, thymus, spleen and lymph nodes, macroscopic pathology and histopathological evaluation of the lymphatic organs/tissues and of the injection sites.

Revised guides for organ sampling and trimming in rats and mice--Part 2. A joint publication of the RITA and NACAD groups

This is the second part of a series of three articles on trimming instructions of rat and mouse protocol organs and tissues in regulatory type toxicity studies, covering the respiratory, male and female genital, and the endocrine systems. The article is based on the experience of the European RITA and American NACAD working groups and is an extended revision of trimming guides published in 1995 (Bahnemann et al.). The optimum localization for tissue preparation, the sample size, the direction of sectioning and the number of sections to be prepared is described organ by organ. These descriptions are illustrated for each organ by a schematic drawing and/or a macro-photograph showing the plane of section as well as a low magnification of the H&E stained slide demonstrating the optimum "end-product". The objectives of this work, as addressed in detail in the first part (Ruehl-Fehlert et al. 2003), are to standardize tissue sampling and trimming, to improve the comparability of historical data obtained from different studies and different laboratories, ensure the presence of all relevant target sites for histopathological evaluation and provide technical advice for preparatory techniques during necropsy, fixation and trimming. dardize tissue sampling and trimming, to improve the comparability of historical data obtained from different studies and different laboratories, ensure the presence of all relevant target sites for histopathological evaluation and provide technical advice for preparatory techniques during necropsy, fixation and trimming.

Effects of epithelial growth factor receptor (EGFR) kinase inhibitors on genetically reconstituted mouse mammary glands

The aim of the study was to determine the effects of a specific epithelial growth factor Receptor kinase inhibitor (EGFR-KI) and Taxol on tumor growth in a novel tumor model.

MATERIAL & METHODS

A genetically engineered tumor model which uses "transgenic" organs in immune competent mice was used. NeuT-transfected immortalized HC11 epithelial cells and primary mouse mammary epithelial cells have been transplanted into the gland-free mammary fat pad of female BALB/c mice. Mammary tumors developed after a latency period of three to four weeks. The mice were thereafter daily orally treated over a 19 or 22-day period with 0, 38, 75, 2 x 75 mg/kg body weight (b.w.) EGFR-KI (n: 7-9 per group) or intravenously with 10 mg/kg b.w. Taxol. After necropsy the histopathological evaluation of the tumors was performed in a coded manner. The proliferation activity of tumor cells was analyzed by laser scanning cytometry (LSC) using anti-Ki67-antibodies.

RESULTS

Oral Treatment with EGFR-KI in this transgenic organ model showed clear antitumor efficacy in a dose-dependent manner in the range between 38 and 75 mg/kg b.w. This antiproliferative effect appears to be minimally increased at 75 mg/kg/day twice per day. For all treatments a strong correlation between the biological behavior of the tumor, histopathology and cell proliferation could be established. In contrast, treatment with Taxol showed no significant reduction of tumor growth or cell proliferation in this model. This new transgenic organ model comprising histopathological evaluation and cell proliferation analysis appears to be a suitable test system for drug candidates that affect specific biochemical pathways. It may have greater predictive nature for clinical effects in humans as compared to conventional tumor models because of its c-erb B2 gene overexpression.

Neutron production from polyethylene and common spacecraft materials

We report experimental measurements of neutron production from collisions of neutron beams with polyethylene blocks simulating tissue at the Los Alamos National Laboratory Neutron Science Center and 1 GeV/amu iron nuclei with spacecraft shielding materials at the Brookhaven National Laboratory AGS.

Distal hypospadias repair with meatal-based flaps on an outpatient basis

We report the results of primary repairs that were performed on 52 consecutive patients with distal hypospadias as an outpatient procedure. A modified Mathieu repair with meatal-based vascularized flap was performed under 2.5 optical magnification using Scottring retractors, traction sutures, micro instruments and fine suture material. A total of 3 patients had complications that required reoperation (5.8%). One of these 3 complications was a urethrocutaneous fistula (1.9%). We found that the repair of distal hypospadias was successful with meatal-based flap using contemporary finer approaches and equipment.

Upper urinary tract manifestations of the VACTERL association

PURPOSE

In patients suspected to have the vertebral, anal, tracheoesophageal, renal, radial, cardiac and limb abnormalities (VACTERL) association we studied the frequency of upper urinary tract anomalies, prevalence of these features, predictability of upper tract pathology and proper screening evaluation.

MATERIALS AND METHODS

From 1991 to 1998 we identified 55 patients with the VACTERL association. Upper urinary tract assessment, including initial renal ultrasound and voiding cystourethrography, and followup data were available for 29 boys and 15 girls. Patients were considered to have the VACTERL association when 3 or more organ systems were involved.

RESULTS

Average followup was 5.4 years. Upper urinary tract involvement was noted in 41 of the 44 patients (93.2%) and vesicoureteral reflux in 17 (25 renal units). Of the kidneys 21 were hydronephrotic without reflux or obstruction, 10 were solitary, 3 were multicystic dysplastic, 8 were obstructed and only 17 were normal. A total of 27 patients (61%) underwent at least 1 genitourinary procedure, primarily ureteroneocystotomy. All children were alive at the last followup.

CONCLUSIONS

The VACTERL association involves multiple serious anomalies. However, these infants generally have a good outcome. Since the upper urinary system is the most common organ system involved, patients should receive prophylactic antibiotics until an initial urological assessment with renal ultrasound and voiding cystourethrography is performed. It is essential for physicians to know that most children with the VACTERL association have urological involvement that requires treatment and long-term management.

Bilateral posterior pelvic resection osteotomies in patients with exstrophy of the bladder

This paper describes a modification of bilateral posterior iliac osteotomies for bladder exstrophy, in which a strip of ilium is resected subperiosteally lateral to the sacroiliac joints, allowing easier anterior closure with less breakdown compared with traditional osteotomies. Thirty-one children underwent repair of bladder exstrophy between 1974 and 1994. Orthopaedic procedures included: closed reduction and cast application in the newborn period (four patients), classic bilateral posterior iliac osteotomies (12 patients), and bilateral posterior resection osteotomies (15 patients). Dehiscence occurred after one closed reduction, five classic osteotomies, and one resection osteotomy. Urinary continence was obtained in four patients who underwent closed reduction, nine patients who underwent classic posterior osteotomies, and nine patients who underwent posterior resection osteotomies.

Analysis of homeobox gene HOXA10 mutations in cryptorchidism

PURPOSE

Cryptorchidism is the most common congenital abnormality of the genitalia. However, its exact etiology remains to be defined. Homeobox (HOX) containing genes have a key role in the morphogenesis of segmental structures along the primary body axis, including the urogenital mesenchyma. In male mice with a targeted deletion of the HOXA10 gene cryptorchidism manifests in the absence of other major defects. Because to our knowledge this gene has never been examined for alterations in humans, we evaluated whether mutations of HOXA10 are associated with cryptorchidism in humans.

MATERIALS AND METHODS

Genomic deoxyribonucleic acid (DNA) was extracted from human blood or tissue samples from 16 noncryptorchid control subjects and 45 cryptorchid boys. To screen for mutations exons 1 and 2 of the HOXA10 gene were amplified individually by polymerase chain reaction using 6 overlapping oligonucleotide primer pairs. Single strand conformational polymorphism (SSCP) analysis of the amplified radiolabeled DNA fragments was performed. Variant band shifts were detected due to abnormal migration of the denatured DNA fragment compared to controls, suggesting an alteration in the DNA sequence. Sequence analysis of these variant bands was then done to define any mutations.

RESULTS

SSCP analysis revealed variants in 2 controls. Of the 45 samples from cryptorchid patients 30 had SSCP variants in exon 1. No variants were found in other regions of the gene. Sequence analysis revealed several DNA polymorphisms in exon 1 in controls and boys with cryptorchidism. Other nucleotide changes (point mutations) were noted only in exon 1 in the DNA of 5 cryptorchid patients, of whom 1 had a 24 nucleotide deletion.

CONCLUSIONS

Our initial analysis of the HOXA10 gene in humans demonstrates that genetic alterations of this gene may be present in some boys with cryptorchidism. HOXA10 polymorphisms exist in normal control subjects as well as in cryptorchid patients. Further analysis of the function of the mutated protein will elucidate the role of this gene as a potential causative factor of testicular descent.

Long-term adjustment issues in patients with exstrophy

PURPOSE

We explored the psychological adjustment of children with bladder or cloacal exstrophy.

MATERIALS AND METHODS

We assessed 29 subjects with a mean age plus or minus standard deviation of 7.8 +/- 3.97 years using age appropriate standard psychological instruments. Psychological adjustment scores in the exstrophy group were compared to the norms of the various instruments. Subjects were divided into dichotomous groups according to several medical and demographic factors. For each factor the differences between the means of the 2 groups on the outcome variables were calculated using a t test.

RESULTS

Children with exstrophy perceived their appearance more positively than the norm. Older children performed more poorly than younger children in adaptive behavior, specifically in skills related to functioning in school. Children who achieved continence after age 4 years were more likely to have problems with acting out behavior. There were no differences in adjustment in boys versus girls, bladder versus cloacal exstrophy, type of continence strategy or gender reassignment versus no reassignment.

CONCLUSIONS

Children with exstrophy did not have clinical psychopathology. Differences existed in adaptive and acting out behavior rather than depression or anxiety, suggesting that improved outcomes may be achieved through a focus on normal adaptation rather than on potential psychological distress.

Androgen receptor gene alterations are not associated with isolated cryptorchidism

PURPOSE

Multiple theories of testicular descent exist but there is no consensus. Cryptorchidism is a component of the androgen insensitivity syndrome, suggesting that testicular descent may be at least partially under the control of androgenic stimulation. To determine whether isolated cryptorchidism may be caused by androgen insensitivity, we screened a population of boys with isolated cryptorchidism for the presence of androgen receptor gene alterations.

MATERIALS AND METHODS

Deoxyribonucleic acid (DNA) was isolated from tissue collected from 21 patients with isolated cryptorchidism during orchiopexy. Patient selection was biased to maximize the likelihood of detection of a genetic etiology of cryptorchidism. The DNA was screened for androgen receptor gene alterations in exons 2 to 8 using single strand conformational polymorphism analysis.

RESULTS

No abnormalities in the androgen receptor gene were detected by single strand conformational polymorphism analysis in any patient.

CONCLUSIONS

Mutations of the androgen receptor gene in the hormone and DNA binding domains of the protein appear to be an unlikely cause of isolated cryptorchidism.

Androgen receptor gene alterations are not associated with isolated cryptorchidism

PURPOSE

Multiple theories of testicular descent exist but there is no consensus. Cryptorchidism is a component of the androgen insensitivity syndrome, suggesting that testicular descent may be at least partially under the control of androgenic stimulation. To determine whether isolated cryptorchidism may be caused by androgen insensitivity, we screened a population of boys with isolated cryptorchidism for the presence of androgen receptor gene alterations.

MATERIALS AND METHODS

Deoxyribonucleic acid (DNA) was isolated from tissue collected from 21 patients with isolated cryptorchidism during orchiopexy. Patient selection was biased to maximize the likelihood of detection of a genetic etiology of cryptorchidism. The DNA was screened for androgen receptor gene alterations in exons 2 to 8 using single strand conformational polymorphism analysis.

RESULTS

No abnormalities in the androgen receptor gene were detected by single strand conformational polymorphism analysis in any patient.

CONCLUSIONS

Mutations of the androgen receptor gene in the hormone and DNA binding domains of the protein appear to be an unlikely cause of isolated cryptorchidism.

Outcome based comparison of surgical approaches for pediatric pyeloplasty: dorsal lumbar versus flank incision

PURPOSE

Dismembered pyeloplasty for the correction of ureteropelvic junction obstruction can be performed through a flank or dorsal lumbar incision. We compared the records of children who had undergone pyeloplasty by each approach to determine if 1 technique was more advantageous.

MATERIALS AND METHODS

We retrospectively reviewed the records of 33 consecutive children undergoing simple dismembered pyeloplasty by a single pediatric urologist from 1992 to 1996. The flank approach was used exclusively in the first group of patients who underwent repair in 1992 to 1993 and the dorsal lumbar incision was used exclusively in the second group after 1993. Data were obtained from hospital and clinic records, and both groups were compared with the 2-tailed t test.

RESULTS

Pyeloplasty was done by dorsal lumbar incision in 16 cases and via the flank approach in 17. One patient in each group had undergone simultaneous bilateral pyeloplasties. Although overall comparison of both groups revealed no differences in operative time, in children older than 1 year pyeloplasty through a dorsal lumbar incision (108.5 minutes) was statistically significantly faster than the flank approach (144.4 minutes). Hospital stay was approximately 2 days shorter in infants who had a dorsal lumbar (25.7 hours) versus a flank incision (73 hours), and this difference did reach statistical significance if the bilateral pyeloplasty patients were excluded. Hospital costs were less for the dorsal lumbar group but the difference was not statistically significant. Success and complication rates were similar between groups with 2 patients in each group requiring additional procedures. Review of other series of repair of ureteropelvic junction obstruction demonstrated that the dorsal lumbar repair had equivalent or shorter operative times and lengths of hospitalization compared to newer endoscopic methods, and the outcomes were superior.

CONCLUSIONS

The dorsal lumbar incision is a safe and efficacious approach to pyeloplasty and may be more cost-effective. In our series it was significantly faster in patients older than 1 year and resulted in shorter hospital stays in those younger than 1 year old.

Pediatric pyeloplasty: outcome analysis based on patient age and surgical technique

OBJECTIVES

To analyze our experience with open pyeloplasty, with specific emphasis on procedural outcome on the basis of patient age, surgical technique, complication rate, and complication management.

METHODS

All patients from 1974 to 1994 who underwent pyeloplasty at our institution were included in our review. Charts were analyzed for age at presentation, presenting signs and symptoms, type of surgical reconstruction, complications and treatment, and final outcome.

RESULTS

From 1974 to 1994, 234 pyeloplasties were performed in 227 patients (108 less than 1 year old, 119 more than 1 year old). The percentage of children less than 1 year old increased throughout: 24% for 1975 to 1980, 37% for 1981 to 1990, and 69% for 1991 to 1994. Presenting signs and symptoms varied according to the age of the child at pyeloplasty. For children less than 1 year old, these were prenatal ultrasound in 86 (79%), urinary tract infection (UTI) in 9 (8%), and abdominal mass in 5 (4.6%). For children more than 1 year old, these were pain in 57 (48%), UTI in 29 (24%), hematuria in 12 (10%), and prenatal ultrasound in 3 (2.5%). Reconstruction was a dismembered pyeloplasty in all cases. The majority of patients in both age groups underwent a nonintubated repair (less than 1 year old, 99 of 114; more than 1 year old, 102 of 120). Postoperative results were evaluated by ultrasound or intravenous urography, with improvement or stable results in 95% of children less than 1 year old and in 96% of children more than 1 year old. Complications included UTI in 18 patients (7.7%), recurrent obstruction in 5 (2.1%), and persistent leak in 4 (1.7%). The complication rate was not related to age.

CONCLUSIONS

The nonintubated, dismembered pyeloplasty is an excellent technique for all age groups and has a low complication rate.

Comparison of onlay and tubularized island flaps of inner preputial skin for the repair of proximal hypospadias

PURPOSE

Transverse island flaps of inner preputial skin have provided a reliable technique for the repair of proximal hypospadias. The flap may be used to create a neourethra by tubularizing the flap after urethral transection or applying the flap as an onlay patch onto an intact urethral plate. We retrospectively analyzed our experience with these 2 techniques to compare outcomes.

MATERIALS AND METHODS

During 11 years 132 patients underwent hypospadias repair by a single surgeon using an onlay (58) or tubularized (74) island flap technique. Surgical results were reviewed retrospectively.

RESULTS

At a mean followup of 20.3 months the overall complication rate was 36% for tubularized and 31% for onlay repair, and fistula rates were 14 and 17%, respectively. Despite similar fistula rates tubularized repairs tended to have larger fistulas that required more complex repair (p = 0.0147). In 9 patients who underwent tubularize repair diverticula developed, whereas no diverticula developed after onlay repair (p = 0.0162). The rates of urethral stricture, wound infection, residual chordee and cosmetic complications were not statistically significantly different between repairs. The use of double faced repair in 30 patients provided no difference in outcome in comparison to the overall study cohort.

CONCLUSIONS

Hypospadias repair using transverse island flaps offers reliable and durable outcomes. While overall complication rates were not greatly different between tubularized and onlay flap repairs, onlay repair tended to result in fistulas of smaller size and diverticula did not develop.

A renal size nomogram for the patient with myelomeningocele

PURPOSE

Renal anatomy and function are usually monitored in the myelomeningocele population using routine ultrasound as the child grows. Clinical questions arise when a renal unit is of marginal size when evaluated with nomograms derived from normal patient populations. Our goal was to construct a renal size nomogram using ultrasound for the myelomeningocele population to help the clinician identify abnormal growth.

MATERIALS AND METHODS

We reviewed the charts and radiological files of 96 patients with myelomeningocele followed at our institution. Images of 930 renal units were included to construct the nomogram. Patients were excluded from study due to hydronephrosis or hydroureter, solitary kidney, recurrent symptomatic urinary tract infection, vesicoureteral reflux, reconstructive surgery or known high bladder storage pressure.

RESULTS

A renal size nomogram was constructed by plotting patient age against maximal renal length on real-time ultrasound. Expected mean and standard deviations were calculated for each age group.

CONCLUSIONS

Previous studies using excretory urography have shown that kidneys in the myelomeningocele population are smaller than in a healthy control population. Ultrasound is now the modality most commonly used to monitor renal anatomy. The creation of a renal nomogram based on ultrasound should help the clinician identify abnormal renal growth more accurately.

Molecular biology and function of the androgen receptor in genital development

PURPOSE

The rapidly growing field of molecular biology has caused exponential growth in our knowledge of the processes of embryogenesis. Since the cloning of the androgen receptor gene in 1988, investigators have been able to clarify many of the molecular events of male sexual differentiation that are mediated through the androgen receptor. We reviewed the current state of knowledge of the androgen receptor and its role in male genital development.

MATERIALS AND METHODS

An intensive literature search was conducted to review reports on the androgen receptor and sexual differentiation since 1988. This review also includes ongoing research from our laboratory on the role of the androgen receptor in human genital development, as well as collaboration with other investigators.

RESULTS

We reviewed the basic molecular biology of androgenic action mediated through the androgen receptor. This information has been integrated into the current understanding of human male sexual differentiation to clarify how androgens virilize the undifferentiated embryo. Defects in function of the androgen receptor may be manifested as a spectrum of phenotypes of the androgen insensitivity syndrome, and these phenotypes of male pseudohermaphroditism have been reviewed on a clinical and molecular basis. New molecular techniques have augmented the evaluation and diagnosis of the androgen insensitivity syndrome, and some groups have successfully diagnosed the condition prenatally.

CONCLUSIONS

Basic scientific research of androgen receptor function and its role in male sexual development has provided a clearer understanding of the mechanisms responsible for the spectrum of defects secondary to the androgen insensitivity syndrome. This knowledge will enable clinicians to offer more accurate diagnosis and insightful counseling to affected patients and their families.

Androgen receptor gene mutations are rarely associated with isolated penile hypospadias

PURPOSE

Hypospadias has no known single etiology but it has been linked to androgen insensitivity caused by mutations of the androgen receptor gene. The purpose of this study was to search for such mutations in cases of various degrees of isolated hypospadias to determine whether such an association exists and, if so, with any particular anatomical subgroup.

MATERIALS AND METHODS

Isolated deoxyribonucleic acid from the penile tissue of 40 patients undergoing reconstructive surgery was screened for mutations of the coding regions of the androgen receptor gene using single strand conformational polymorphism analysis. In cases with abnormal single strand conformational polymorphism findings sequence analysis of the deoxyribonucleic acid was performed to define the mutation.

RESULTS

A missense mutation of exon 2 of the androgen receptor gene was noted in 1 patient with isolated distal penile shaft hypospadias. Sequence analysis revealed that the mutation changed amino acid residue 546 from proline to serine. No abnormalities were detected in the other 39 patients.

CONCLUSIONS

Isolated distal shaft hypospadias is associated with mutations of the androgen receptor gene but these mutations appear to be a rare cause of hypospadias.

The role of surgery in the management of pediatric pelvic rhabdomyosarcoma

PURPOSE

We assessed the role of surgery, particularly exenteration, in the treatment of children with lower urinary tract and pelvic rhabdomyosarcoma.

MATERIALS AND METHODS

We treated 23 children with bladder and/or prostate (11), or pelvic retroperitoneal tumors (12). Initial management was tumor resection in 6 cases, anterior pelvic exenteration in 5 and biopsy only in 12, combined with chemotherapy in 23 and radiotherapy in 20.

RESULTS

The bladder salvage rate for surviving patients with pelvic tumors was 92% versus 27% for those with prostate/bladder tumors. Estimated 5 and 10-year survival probability for patients with pelvic retroperitoneal tumors was 49 +/- 50% compared to 81 +/- 24% for those with bladder and/or prostate tumors (log rank test, p = 0.11).

CONCLUSIONS

Exenterative surgery is frequently required to achieve a durable complete response.

Repair of hypospadias complications using the meatal based flap urethroplasty

While long used for primary hypospadias repair, meatal based flap urethroplasty has not been widely considered a viable alternative for a secondary procedure. We reviewed 200 patients who underwent meatal based flap urethroplasty and identified 9 (4.5%) who underwent the procedure for correction of complications of previous hypospadias repair, including urethrocutaneous fistula, severe meatal retraction, persistent chordee and hair in the urethra. The complication was corrected with a single operation in 8 of the 9 patients (89%). A single small fistula developed in 3 patients, which closed spontaneously in 2 and required another procedure in 1. Meatal based flap urethroplasty should be considered for correction of distal complications of hypospadias repair.

Current indications for cutaneous ureterostomy

OBJECTIVE

To assess the current indications for cutaneous ureterostomy in children.

METHOD

A total of 32 children underwent cutaneous ureterostomy at Texas Children's Hospital from 1975 to 1990. Medical records were reviewed to determine the urologic diagnosis, the indication for urinary diversion, the type of ureterostomy performed, and the outcome for each patient.

RESULTS

Twenty patients underwent loop cutaneous ureterostomy (LCU) or pyelostomy and 12 patients underwent end cutaneous ureterostomy (ECU). The main indication for LCU was obstructive uropathy unresponsive to lower urinary tract drainage, and the most common cause was posterior urethral valves. Other indications for LCU included obstruction requiring delayed surgical correction, high-grade reflux into a solitary kidney, and obstruction with infection. The children who required ECU were an older, more diverse group than those who underwent LCU. The main indication for ECU was poor bladder function secondary to a variety of congenital anomalies, including prune-belly syndrome, posterior urethral valves, bladder exstrophy, and urogenital sinus defect.

CONCLUSION

LCU is easy to perform and is an excellent method for achieving temporary upper urinary tract drainage. ECU is suited for long-term or permanent urinary diversion in children with at least one dilated ureter, and can provide a socially acceptable stoma when delayed reconstruction is necessary. Many children who were "permanently" diverted by ECU may be undiverted using newer reconstructive techniques.

In vitro model of the inner parts of a vessel wall with cultured human vascular cells

BACKGROUND

Transfilter culture systems with enzymatically isolated human vascular cells were established to imitate the morphologic situation of the inner parts of a vessel wall.

METHODS

In transfilter cultures, only smooth muscle cells were seeded on one side of the filter, whereas in transfilter cocultures, smooth muscle cells were cultivated in the presence of confluent or nonconfluent (injured) endothelial cells on the other side of the filter. The filter mimics the porous internal elastic lamina. Fourteen days after seeding, cultures were fixed, embedded in Araldite (Serva, Heidelberg, Germany), and prepared for histologic examination (light microscopy, indirect immunofluorescence staining of von Willebrand factor- and alpha-smooth muscle actin-antigen).

RESULTS

In transfilter cultures, smooth muscle cells migrated through the pores to the opposite side of the filter, replicated there, and formed fibromuscular proliferates (two to four layers of smooth muscle cells). The proliferation rates of the smooth muscle cells were similar on both sides of the filter and showed an optimum rate on day 4 in culture as determined by 5-bromo-2'-deoxyuridine labeling. By cocultivating a confluent endothelial cell layer on one side of the filter, migratory activity of smooth muscle cells was inhibited. However, when smooth muscle cells were cultivated together with proliferating endothelial cells (injured state), proliferation of smooth muscle cells was massively stimulated (up to 12 layers of smooth muscle cells).

CONCLUSIONS

The results indicate that the confluency of the endothelial cells and their proliferation rate influence the migratory and proliferative behavior of smooth muscle cells. The transfilter system may be a suitable model for prescreening of potential antiproliferative and antiarteriosclerotic drugs.

Fc receptor expression, concanavalin A capping, and enzyme content of bovine neonatal neutrophils: a comparative study with adult cattle

The increased susceptibility of newborns to infection may in part be related to impaired in vitro functions of neonatal polymorphonuclear neutrophils (PMNs). To evaluate early steps in the activation cycle of bovine PMNs we determined the expression of Fc receptors (FcRs) with an erythrocyte rosetting assay utilizing bovine anti-sheep immunoglobulin G2 IgG2 and the accumulation of ligand receptor complexes or "caps" with fluorochrome-coupled concanavalin A (Con A caps) on neutrophils from adult (A-PMN) and newborn (N-PMN) bovines. In addition, the levels of myeloperoxidase (MPO) and alkaline phosphatase (AP) were determined. FcR expression is reduced in N-PMNs (P less than .001), in contrast to results observed with human N-PMNs. Basal capping of Con A binding sites is reduced (P less than .05) in N-PMNs but is enhanced (P less than .001) upon pretreatment with colchicine (0.5, 5.0, and 50.0 microns). These findings are again contrary to results observed with human N-PMNs. Consistent with findings in human neonates, however, are reduced levels of cellular MPO (P less than .05) and elevated cellular AP (P less than .001) in the neonate. The functional significance of elevated AP levels and altered Con A capping in N-PMNs is unclear. However, diminished expression of FcR could potentially contribute to impaired adherence and phagocytosis of bacteria, and reduced activity of neutrophil MPO could indicate weaker microbicidal capacity of neonatal cells. The demonstrated impairment of N-PMN functions could potentially contribute to reducing the effectiveness of the cellular host defense system in neonatal calves.

In vitro aggregation of bovine neonatal neutrophils. A comparative study with adult cattle

Deficient in vitro functions of neonatal neutrophils have been reported in various species. They may be functionally related to the well-known susceptibility of newborn individuals to microbial infections. To evaluate an early step in the sequence of neutrophil activation, neutrophils from adult cows (A-PMN) and newborn calves (N-PMN) were stimulated with zymosan-activated plasma (ZAP) or with the lipid mediator platelet-activating factor (PAF): Aggregation was recorded kinetically in a standard aggregometer and measured quantitatively as the area under the aggregation curve (AUAC). The mean +/- SEM of the AUAC of the first 2.5 min of the reaction induced with ZAP was similar in N-PMN and A-PMN. However, N-PMN deaggregated only partially, whereas A-PMN deaggregated almost completely (P less than 0.05). This may indicate a mechanism of microvascular sequestration in vivo with the potential to inhibit chemotaxis. PAF (10(-5)-10(-10) M) aggregated N- and A-PMNs similarly and dose-dependently with a maximal reaction at 10(-6) M. Inhibition of aggregation induced by 10(-6) M PAF was evaluated by preincubation with four antiinflammatory drugs: dexamethasone (Dex: 5.1, 51.0, 510.0 microM), flumethasone (Flu: 12.2 and 122.0 microM), phenylbutazone (PB: 0.33 and 3.3 mM), and flunixin meglumine (Flxin: 51 and 510 microM). Dex and Flu each inhibited (P less than 0.05) PAF-induced N-PMN aggregation at the highest dose, and A-PMN aggregation at the two higher doses. PB and Flxin each inhibited aggregation of N- and A-PMNs at all doses used. We compared the inhibition rate in both age groups and could demonstrate that Dex, Flu, and Flxin each at the highest dose, and PB at all doses used, inhibited PAF-induced aggregation less (P less than 0.05) in N-PMNs than in A-PMNs. These functional differences indicate hyperirritability of N-PMNs, and they need further elucidation to help understand mechanisms of increased neonatal susceptibility.

Chemotactic competence of neutrophils from neonatal calves. Functional comparison with neutrophils from adult cattle

Neonates demonstrate an increased susceptibility to infection. Defects in locomotory functions of newborn neutrophils may play a crucial role in this context. We therefore compared the migratory response of newborn (N-PMN) and adult (A-PMN) bovine neutrophils in a microwell filter assay. Stimulation with four different endotoxins (E. coli O128B:4 and O55B:5; S. abortus equi; S. typhimurium), with zymosan-activated plasma (ZAP) and with C5a induced dose-dependent migration of A-PMNs and N-PMNs. Migration of unstimulated cells and of cells stimulated with diluted ZAP or C5a was higher (P less than 0.05) in N-PMNs. Migration of A- and N-PMNs towards C5a was inhibited (P less than 0.001) by preincubation with either a steroidal (122 microM flumethasone) or nonsteroidal (3.3 microM phenylbutazone) antiinflammatory drug. Migratory responses of N-PMNs were inhibited less by SAIDs than were responses of A-PMNs (P less than 0.05); indeed dexamethasone slightly enhanced N-PMN responses towards C5a, and 510 microM flunixin meglumine enhanced C5a-induced migration in both age groups. Endotoxins from E. coli O55:B4, S. abortus equi, and S. typhimurium induced a higher rate of migration (P less than 0.05) in N-PMNs. In contrast to the above findings, measurement of the maximal distance of migration by the leading-front method did not reveal age-related differences. Migration speed of PMNs was lower after stimulation with C5a than with ZAP, but could be restored partly by adding human vitamin D-binding protein (Gc-globulin). The demonstrated hyperirritability of bovine N-PMNs represents a major functional difference to neonatal neutrophils from other species, including man. It may additionally be related to altered PMN functions and neonatal disease susceptibility.

Nephrogenic adenoma of the bladder in children

Nephrogenic adenoma is an uncommon entity, particularly in children. This benign lesion is believed to represent urothelial transformation in response to trauma or inflammation. Current treatment is local resection with fulguration of the base of the lesion, long-term antimicrobial therapy and periodic cystoscopy. Our 2 cases support not only the urothelial transformation theory but raise the possibility that immunosuppression may be a contributing factor in these lesions.

Individualized treatment of ureteroceles

We reviewed 52 children with ureteroceles in an effort to evaluate the various facets of this disorder that influenced our surgical management. There were 12 single system ureteroceles and 40 duplex system ureteroceles. Total reconstruction was performed in 16 duplex system and 8 single system ureteroceles, of which 88 per cent required no further surgery. Upper pole heminephrectomy or ureteropyelostomy with partial ureterectomy was performed in 22 patients with duplex system ureteroceles with the goal of obviating lower tract surgery, of whom 12 (55 per cent) required subsequent surgery. In 6 patients, 4 with single system and 2 with duplex system ureteroceles transurethral incision of the ureterocele was the initial procedure with the expectation that improvement in function and hydronephrosis would facilitate subsequent lower tract surgery. Two of these patients required subsequent reconstruction. Recommendations regarding management are based on initial pathological condition, patient age and the presence of a single or duplex system ureterocele.

Covered exstrophy and visceral sequestration in a male newborn: case report

We report a case of a male newborn with complete epispadias and an umbilical lesion. Histological examination of the surgically removed lesion revealed a colonic remnant with no communication to the underlying bowel. This entity is one of the exstrophy/epispadias complex variants known as covered exstrophy with sequestered bowel, and is case 4 in the world literature. Simple excision of the lesion was accomplished with staged correction of the epispadias planned.

Vesicoureteral reflux in boys

The natural history of vesicoureteral reflux in children is well documented. In most series girls comprise the majority of the children followed. We reviewed the presentation and course of 86 boys with primary vesicoureteral reflux to define the nature of reflux in that selected population. Of the boys 25 per cent presented when they were less than 3 months old and the youngest tended to have the most severe reflux. Presentation was usually with urinary tract infection but 14 per cent had dysfunctional voiding symptoms without urinary tract infection. Based upon their presentation and initial evaluation the patients were allocated to 1 of 3 treatment protocols: observation, chemoprophylaxis or surgery. No renal parenchymal loss was detected in the boys on observation. Surgical therapy was free of serious complications. Over-all, this modified approach to the management of reflux in boys is acceptable although further followup will be required to confirm these initial conclusions.

Open catheter drainage after urethral surgery

A retrospective analysis of 100 patients, each managed by an intubated urinary diversion after undergoing repair of hypospadias and/or chordee or for a complication of previous urethral surgery, was performed to determine whether there was any difference in the incidence of postoperative urinary infection relative to the technique of catheter drainage (closed or open). In group 1 (50 patients) a traditional closed urinary drainage system was used, while in group 2 (50 patients) an open drainage system into doubled diapers was used. No significant difference in occurrence of urinary tract infections could be identified. Urinary infections occurred equally (24 per cent) in each group regardless of whether antibiotics were used postoperatively. Our results suggest that open urinary drainage using the double diaper technique is a safe and effective method of short-term catheter management after pediatric urethral surgery. This technique is comfortable for the patient, and is easy for parents to understand and master.

Hypospadias repair by bladder mucosal graft: an initial report

Surgical correction of major hypospadias defects is a challenging problem. Bladder mucosa has been reported as an excellent tissue for construction of a neourethra. We used bladder mucosa in 13 boys to create 15 neourethras when there was inadequate preputial skin to perform a vascularized pedicle flap or a free preputial graft. In 3 cases a bladder mucosa graft was used for initial repair of the hypospadias. All other boys had undergone prior hypospadias surgery. In 4 boys the initial result was satisfactory. Seven minor complications occurred in 5 boys, while 4 had more major complications. In 2 boys severe problems with stricture necessitated graft replacement and a satisfactory outcome has not been achieved. Our problems with stricture and stenosis seem to be related to the use of a subcutaneous tunnel for the graft bed and coring of the glans to create the meatus. Over-all, in 11 of the 13 boys the bladder mucosal graft provided an excellent resolution of the complex problem with easily managed postoperative complications.

Use of the AS800 device in exstrophy and epispadias

Urinary continence is one of the more difficult goals to achieve in patients with exstrophy or epispadias. The artificial genitourinary sphincter provides an alternative to reconstruction of the bladder neck for management of this problem. Although excellent continence can be obtained with bladder neck reconstruction, results of a second procedure of this type seldom are reported. We used the AS800 device in 16 patients with exstrophy and epispadias, 13 of whom had undergone a prior bladder neck operation. We defined our results as total success and continence success, and have achieved over-all rates of 69 per cent (excludes those awaiting revision) and 90 per cent (those with an active device), respectively. Although the frequency of revision and erosion was significant, the ultimate outcome in this difficult patient group was satisfactory.

Management of the penile shaft skin in hypospadias repair: alternative to Byars' flaps

Two variations for resurfacing the penile shaft skin after repair of hypospadias defects are described. These techniques have been used in an effort to prevent some of the skin tags, tension at the penoscrotal angle, and oblique suture lines that may occur with the traditional Byars' flaps.

One-stage reconstruction of moderately severe hypospadias

Single stage repair of moderately severe degrees of hypospadias with correction of chordee and reconstruction of the neourethra presents a difficult challenge for the surgeon. Traditionally, a 2-stage approach to correct these defects has been used. However, more recently a 1-stage repair with correction of chordee and creation of a neourethra has increased in popularity. From 1978 to 1985 we treated 86 patients with moderately severe hypospadias and chordee with a 1-stage technique using either a transverse island pedicle flap, a Hodgson III hypospadias repair or a free preputial skin graft. Despite an over-all complication rate of 50 per cent, our final results based on cosmesis and function were deemed excellent in 90 per cent of the cases. Of the 44 complications 23 were strictures, most frequently at the proximal anastomosis. Two-thirds of these strictures responded to a single dilation with the patient under anesthesia. Our fistula rate was 10 per cent and flap necrosis, meatal stenosis or prolapse and residual chordee accounted for the remaining 12 complications. Our experience indicates that a 1-stage repair for moderately severe hypospadias and chordee can be performed in patients with a satisfactory success rate of more than 90 per cent, minimal morbidity and an acceptable complication rate.

Experience with free grafts in urethral reconstruction

A total of 33 patients underwent hypospadias or epispadias repair by patch or tubular grafts of skin or bladder epithelium from July 1980 to January 1985. Indications included previous circumcision, proximal primary hypospadias, severe chordee alone, inadequate local skin during extended urethroplasty at 2-stage hypospadias repair, multiple previous reconstructions and failed epispadias repair. Genital skin grafts were used in 25 patients, extragenital skin grafts in 4 and bladder epithelial grafts in 4. Complications occurred in 13 patients (39.4 per cent): 8 required reoperation for a fistula, stricture or diverticulum, and 5 underwent internal urethrotomy or urethral dilation. Of the 8 patients 3 needed more than 1 revision. These revisions were short and generally uncomplicated. Final results uniformly were good functionally and cosmetically. Based on our experience and that of others we believe that despite a high incidence of minor complications a free graft serves as an excellent substitute urethra for treatment of a variety of urethral problems in children.

Bladder disruption in the premature male neonate

Bladder injury in children is an unusual event that usually is associated with trauma or a surgical mishap. We describe-2 premature male neonates who were treated by minimal stimulation therapy and systemic paralyzation. Despite normal urological anatomy, each patient had a bladder rupture that we attributed to atony of the bladder coupled with the Credé maneuver, which produced high intravesical pressures.

Urinary tract deterioration associated with the artificial urinary sphincter

In most recent series of artificial sphincter implantations there has been a reduction in mechanical and surgical complications, with continence rates approaching 90 per cent. Despite initially excellent results in 47 children, with increasing durations of followup we noted a transient hydronephrosis related to incomplete bladder emptying in 5 and a persistent physiological alteration of detrusor dynamics consisting of a rigid, noncompliant bladder in 7. Preoperatively, all patients had had indepth radiological studies and most had a urodynamic evaluation, and were considered to be excellent candidates. The etiology of these alterations is not understood at this time. Bladder and even upper tract deterioration can occur without the appearance of urinary leakage. Therefore, children with an artificial sphincter must be monitored indefinitely with semiannual assessment of the upper tracts and periodic urodynamic evaluation.