A cross-sectional nationwide survey on esophageal atresia and tracheoesophageal fistula.

BACKGROUND: Our study aims at disclosing epidemiology and most relevant clinical features of esophageal atresia (EA) pointing to a model of multicentre collaboration. METHODS: A detailed questionnaire was sent to all Italian Units of pediatric surgery in order to collect data of patients born with EA between January and December 2012. The results were crosschecked by matching date and place of birth of the patients with those of diagnosis-related group provided by the Italian Ministry of Health (MOH). RESULTS: A total of 146 questionnaires were returned plus a further 32 patients reported in the MOH database. Basing on a total of 178 patients with EA born in Italy in 2012, the incidence of EA was calculated in 3.33 per 10,000 live births. Antenatal diagnosis was suspected in 29.5% patients. 55.5% showed associated anomalies. The most common type of EA was Gross type C (89%). Postoperative complications occurred in 37% of type C EA and 100% of type A EA. A 9.5% mortality rate was reported. CONCLUSIONS: This is the first Italian cross-sectional nationwide survey on EA. We can now develop shared guidelines and provide more reliable prognostic expectations for our patients.

Focus on paediatric and adolescent varicocoele: a single institution experience.

The aim of this study was to report our long-term diagnostic and surgical outcome during the last 18 years, in paediatric and adolescent management of varicocoele. The present retrospective study enrols 374 patients observed at our institution between 1994 and 2011. Patients were divided into three groups: Group A includes 142 youngsters and adolescents treated with open surgery for left varicocoele, in which a pre-operative CDUS was not performed; Group B includes 65 patients treated with open surgery in which a pre-operative CDUS evaluation was carried out, to assess varicocoele haemodynamic pattern and testicular volume. Group C includes 167 patients treated by laparoscopy and with pre-operative CDUS assessment. For all groups post-operative follow-up consisted of CDUS evaluation performed 1, 3, 6, 12 months after surgical treatment, than every year. Persistence/recurrence of varicocoele, testicular volume and presence of hydrocele were evaluated. Recurrence rate was significatively higher in group A (11.2%) than B (no recurrence, p = 0.003) or C (no recurrence, p = 0.000). Post-operative hydrocele was not significantly observed overall in group A in 9.8% of cases (13% if tunica vaginalis was left untouched, 4.2% if everted or resected p = 0.005), in group B in 3% and in group C in 7.1% of cases (p = NS). In conclusion, open and laparoscopic surgery offers similar results. In our opinion, the key-point in paediatric and adolescent varicocoele is not the surgical approach to use, but the exact diagnosis. Careful CDUS evaluation is, in our opinion, a valid, safe, cost-effective and immediate tool to accurately detect all refluxing venous system and for achieving a comprehensive evaluation of the vascular anatomy of varicocoele in paediatric and adolescent age. Laparoscopic Palomo or open subinguinal microsurgical varicocelectomy offer similar results in terms of recurrence; meanwhile the use of a lymphatic sparing surgery with or without blue-dye is recommended to reduce post-operative hydroceles.

Pediatric sialolithiasis distinctive characteristic in radiological imaging.

AIM: Aim of the present paper was to investigate the imaging and related clinical characteristics of sialolithiasis in Italian pediatric population trying to determine the difference between pediatric and adult. METHODS: Twenty-nine pediatric patients (age range 1-17 years) with pain and postprandial swelling and/or purulent discharge in the salivary gland areas were referred to radiology department after pediatric ear, nose and throat (ENT) evaluation. They all were submitted to ultrasound examination of the main salivary glands. Multidetector computed tomography (MDCT) only was performed in 2/6 patients, in 2/6 patients both sialography and MDCT were performed due to inconclusive MDCT features, 2/6 only sialography was performed. Sialoliths were classified on their location and size. RESULTS: In 6 out of 29 patients (4 males, 2 females, age range 1-17 years) salivary stones were detected. Sialoliths were detected in 5/6 patients in the submandibular gland and 1/6 in the parotid gland. All sialoliths, excepted for a case of multiple sialoliths, were located in the distal part of the main salivary ducts. CONCLUSION: Imaging characteristics of sialolith in pediatric group are similar than in adult population in few aspects. In fact sialoliths are smaller in size and located more frequently in the distal part of the main salivary duct, than in adult, making sialography cannulation more complex and requiring short thickness in MDCT.

[Duodenal perforation due to an abdominal drain placed after appendectomy in a child.

Insertion of abdominal drainage after appendectomy is controversial. We report on a case of duodenal perforation due to a silastic open drainage tube placed in the right para-colic gutter after appendectomy for perforated appendicitis. This case offers a clue against too liberal usage of abdominal drainage after appendectomy. Conservative management of bowel perforations secondary to abdominal drainages should be attempted in the absence of generalised peritonitis.

Comprehensive laparoscopic approach to pediatric varicocele based on preoperative color Doppler ultrasound assessment.

BACKGROUND: This study aimed to assess whether laparoscopic treatment for any kind of varicocele is possible after preoperative identification of refluxing veins by color Doppler ultrasound (CDUS). METHODS: At the authors' institution, 98 patients with a median age of 11.3 years (range, 7.1-16 years) were evaluated for a left varicocele. Preoperatively, all the patients underwent ultrasound scan assessment of testicular volume and CDUS to rule out reflux into the internal spermatic vein (ISV), deferential vein, or cremasteric vein. In all the patients, laparoscopic division of the spermatic artery and veins was performed as close as possible to the internal inguinal ring. The other vessels were coagulated and divided if shown to be refluxing on CDUS. RESULTS: Color Doppler ultrasound showed reflux only in the ISV in 87 cases (88.7%), but in both the ISV and the deferential in the remaining 11 cases (11.2%). During a median follow-up period of 18 months (range, 6-49 months), none of the authors' patients experienced varicocele recurrence either clinically or according to CDUS scanning. The median left testicular volume increased significantly postoperatively. CONCLUSION: The proposed technique based on laparoscopic interruption of the ISV and testicular artery very close to the internal inguinal ring, meticulous CDUS assessment to rule out reflux in the deferential vein, and coagulation of refluxing deferential veins allows successful laparoscopic treatment of most varicoceles.

Polycystic ovary and gonadoblastoma in Turner's syndrome.

Turner's syndrome (TS) is characterized by typical facial features, short stature, hypergonadotropic hypogonadism, streak gonads, infertility, hearth and kidney malformations. Typical karyotype is 45,X0; however, 6% of TS have mosaic patterns including Y chromosome or fragments of Y. This karyotype is a risk factor of developing a dysgerminoma in dysgenic gonads. Furthermore, rare cases of polycystic ovary are described in young-adult patients with TS. We describe the clinical case of a 12-year-old girl with TS treated with GH who showed a good response to treatment. She developed an ovary with histological polycystic pattern and a contralateral gonadoblastoma in the streak gonad. Laparoscopic gonadectomy was performed, with a good prognosis. Of remark is the opportunity to carry out gonadectomy in prepubertal age in girls with TS and Y chromosome material. This is a rare precocious case of polycystic ovary in TS, with different evolution in the two gonads with different histological differentiation.

Primary repair in esophageal atresia. The results of long term follow-up.

AIM: The aim of this study was to assess the impact of postoperative morbidity during a long-term follow-up (6-12 years) in children with esophageal atresia treated at birth by primary anastomosis. METHODS: Fifteen children with esophageal atresia and tracheoesophageal fistula were surgically treated at birth and their follow-up was extended to at least 6 up to 12 years. Data included clinical examination, evaluation of nutritional habit, continuous video recording of barium esophagogram, esophageal manometry, 24-h esophageal pH-monitoring and esophageal endoscopy. RESULTS: All the 15 patients completed the clinical evaluation and the set of tests. In the first 6 years, mild dysphagia and gastroesophageal reflux (GER) was observed in 3 cases whereas GER without dysphagia in 4 cases. These 7 patients were informed about simple nutritional behaviours to minimize symptoms and treated with H2-blockers. At long-term twelve-year analysis, all patients were between 50 degrees and 75 degrees percentile of expected growth. It was not referred peculiar food restrictions. Five patients showed mild dysphagia with solid foods; early satiety, epigastric burning and regurgitation were less frequent. Furthermore they showed multiple non-peristaltic body contractions at esophagogram and moderate impairment of esophageal motility at esophageal manometry. The 24-h esophageal pH-monitoring showed normal patterns in all patients. No major lesions of esophageal mucosa were detected at esophagoscopy. CONCLUSIONS: Although GER and esophageal dysmotility are reported as frequent findings in patients who underwent primary repair for esophageal atresia, these disorders don't cause any relevant impairment to the quality of their nutritional habit.

Suture materials: do they affect fistula and stricture rates in flap urethroplasties?

INTRODUCTION: The effect of suture materials on urethroplasty complications is debated. Indeed, materials with a delayed absorption might either reduce the incidence of fistulas by ensuring a prolonged approximation of neo-urethral edges or increase the risk of urethral strictures due to a prolonged tissue reaction during suture absorption. We retrospectively evaluated the role of suture materials in the complication rate of urethroplasty procedures performed in our institution over a 10-year period. PATIENTS AND METHODS: Three hundred and thirty-six boys undergoing a flap procedure (parameatal based, preputial tube, or onlay preputial flap) for hypospadias repair were considered for this study. The patients were stratified into two groups according to the suture material used for urethroplasty. Polyglactin (Vicryl), a polyfilament with intermediate absorption, was used in 254 group A patients, whereas polydioxanone (PDS), a monofilament with prolonged absorption, was used in 82 group B patients. The success of a one-stage repair and stricture and fistula rates were evaluated. RESULTS: A successful one-stage repair was achieved in 82% of the group A and in 83% of the group B patients (p = 0.97). No statistically significant differences were noted in fistula and/or stricture rates in the two groups, even considering each procedure separately. CONCLUSIONS: This series suggests that suture materials do not affect the complication rate in flap urethroplasty procedures. Appropriate technique, meticulous surgery, and surgeon experience seem to be more crucial factors. A randomized trial is warranted.

Transurethral incision of duplex system ureteroceles in neonates: does it increase the need for secondary surgery in intravesical and ectopic cases?

OBJECTIVE: To evaluate the relevance of ureterocele ectopia and associated reflux on the outcome of duplex system ureteroceles (DSU) after neonatal transurethral incision (TUI). PATIENTS AND METHODS: The study included 41 neonates with a diagnosis of DSU; the ureterocele was ectopic in 24 (58%). Before TUI, vesico-ureteric reflux (VUR) was present in 13 lower moieties (32%) and seven contralateral ureters (17%). TUI was always performed within the first month of life. The follow-up and management were tailored for each patient from the findings at ultrasonography, voiding cysto-urethrography and renal scintigraphy. Results of intravesical and ectopic DSU were compared using Fisher's exact test. RESULTS: TUI was effective in allowing ureteric decompression in all but one patient (2.4%). After TUI, VUR ceased in six lower ipsilateral moieties and in two contralateral ureters, while new VUR occurred in three contralateral kidneys. De novo VUR in the punctured moiety appeared in 13 cases (32%). Nine upper poles were not functioning. Twenty-one patients (51%) required secondary surgery. Ureteric reimplantation was indicated exclusively for reflux in the punctured moiety in only in two cases (5%), while in a further two iatrogenic reflux in a nonfunctioning upper moiety required total heminephro-ureterectomy. There was no significant difference between intravesical and ectopic ureteroceles in the occurrence of VUR in the punctured moiety, rate of nonfunctioning upper poles or need for secondary surgery. CONCLUSIONS: About half of the patients with a DSU need secondary surgery, but this is rarely indicated for de novo reflux in the punctured moiety only. The need for secondary surgery was greater whenever there was associated reflux before endoscopic incision. There was no difference in the outcome of intravesical and ectopic ureteroceles and such distinction seems no longer to be of clinical relevance.

Needle perforation of the bowel in childhood.

Accidental ingestion of foreign bodies occurs frequently in childhood. The majority of them are passed spontaneously, and conservative management generally is recommended for foreign bodies in the stomach and duodenum. However, in some cases, operative intervention should be considered to prevent undesirable complications, such as intestinal perforation. Two cases of intestinal perforation owing to accidental ingestion of a needle are reported.

Sub-inguinal interruption of dilated veins in adolescent varicocele: should it be considered a gold standard technique?

AIM: Surgeons of varicocele are at present still searching for a gold standard technique, which can correct varicocele without any recurrences, maintaining optimal testicular function, having got minimal current and future morbidity and being cost effective. We evaluated the presence of these criteria in the technique of sub-inguinal dilated vein interruption. METHODS: Between 1994 and 2001, 142 youngsters and adolescents underwent surgery for varicocele repair at our hospital. Average patient age was 12.4 years (range 8 to 15). One-hundred-six cases (74.7%) were grade III varicocele, while 36 (25.5 ) were grade II. Grade II varicoceles underwent surgery only if associated with scrotal discomfort, testicular softness or hypotrophy of the affected testis (differential volume between the 2 testicles more than 20% or more than 2 ml ). Varicoceles were repaired using a subinguinal ligation of intrafunicular and extrafunicolar dilated veins. The testicular vaginalis was not touched in 46 children (Group A) but it was reversed in 42 and resected in the other 54 cases to prevent postoperative hydrocele. RESULTS: In 126 cases (88.7%) varicocele disappeared after surgery, in 12 (8.4%) a mild residual vein dilatation persisted but without any sign of reflux at color-Doppler ultrasound, in 4 patients a postoperative venous reflux was found. Thus, our recurrence rate is nowadays 2.8%. Average postoperative follow-up was 2.3 years (range 1 to 5 years). No testicular atrophy was observed. Based on our last series, at 1 year follow-up control (26 cases throughout year 2000), mean testicular volume, assessed by ultrasound, increased not significantly after surgery from ml 4.69 (SD+/-1.46) preoperative volume to ml 5.19 (SD+/-1.36) postoperative (p=0.2). CONCLUSION: First of all, we found a recurrence rate of 2.9% similar to the lowest of the other procedures. Regarding morbidity, the main inconvenience consists in postoperative hydrocele. It occurred in 13% of our 1st series (group A), but only in 4.1% of patients after reversion or resection of the vaginalis tunica. Average postoperative testicular volume increases after varicocelectomy in our patients, even if not significantly. About sparing the testicular artery or not it has been demonstrated that ligation of this artery doesn't impair testicular growth up and our own observations confirm this evidence. Thus we believe it to be more useful and safe to interrupt this artery to avoid recurrences due to a periarterial venous network. Finally we can conclude that sub-inguinal ligature of dilated veins, when approached with rigorous understanding of the pathophysiology of varicocele is a very safe procedure and low cost effectiveness.

A giant fetal urinoma in a neonate without detectable obstructive uropathy.

UNLABELLED: Fetal urinoma is an uncommon finding in prenatal investigations. Most previous reports have, almost in every case, referred to the presence of an obstructive uropathy and thus to very high pressure in the upper urinary tract during fetal life. In this paper we present a prenatally detected fetal giant urinoma occurring in the absence of an apparent obstructive uropathy but associated with an ipsilateral vesico-ureteral reflux. CASE REPORT: A 5-day-old boy, born after a caesarean section in the 37th week of gestation, but without any perinatal distress, came under our observation because of the evidence of a right upper quadrant abdominal mass. This mass had already been detected prenatally, when during the 30th week of gestation ultrasound investigation showed a right anechogenic mass occupying more than half of the abdominal fetal profile. At postnatal US scan this liquid mass did not seem to have its own wall and moved the nearest organs laterally and upward. The right kidney was not visualised and no ascites was present. We decided to insert a percutaneous drainage tube to decompress the renal parenchyma; normal urine leaked out from it. Radionuclide 99 mTc-DTPA scan excluded an obstructive uropathy, while voiding cystourethrogram excluded posterior urethral valves but showed a vesico-ureteral reflux. We diagnosed a right-sided giant urinoma correlated with a vesico-ureteral reflux but without any urinary obstruction. DISCUSSION: It is very difficult to find a reasonable explanation for the occurrence of a urinary extravasation as a consequence of a vesico-ureteral reflux as seen in this neonate. We know that an intra-renal reflux can be the final result of high-grade vesico-ureteral reflux, but we find it very strange that this could induce a parenchymal rupture in the absence of a rapid increase of pressure and thus without a urinary stricture or stenosis. We can only assume that a prenatal transient urethral outflow obstruction was the cause of this renal rupture. A syringocoele might be the most probable transitory cause of prenatal obstruction.

Urethrocutaneous fistula repair after hypospadias surgery.

OBJECTIVE: To evaluate and compare the success rates of simple and layered repairs of urethrocutaneous fistulae after hypospadias repair. PATIENTS AND METHODS: The charts of 72 children who developed fistulae after hypospadias repair were reviewed; 39 had a simple closure of the fistula, whereas 32 had a 'pants over vest' repair, in all cases after excluding an impairment of urine outflow. RESULTS: The success rate at the first attempt was 74% for simple closure and 94% for the layered repair; at the second attempt it was 80% and 100%, the difference being statistically significant for both repairs. CONCLUSIONS: Although probably far from an optimal technique for repairing urethrocutaneous fistulae, the pants-over-vest repair allows a good success rate for penile shaft fistulae.

[Cystic dysplasia of rete testis associated with ipsilateral renal agenesis. Case report]. / Displasia cistica della rete testis associata ad agenesia renale omolaterale. Descrizione di un caso clinico.

Cystic dysplasia of the rete testis is a rare abnormality often associated with the ipsilateral agenesis of kidney. This malformation is due to a development defect of the mesonephric duct which is the cause of both the dilation of the testicular rete testis and renal agenesis. A case of this rare malformation, showing all the peculiarities described in the medical literature, is presented. A 3 years-4 months boy was examined for an asymptomatic left scrotal mass; thus, he underwent ultrasonography, which showed a multiple tubular and cystic dilatation of left rete testis, associated with the absence of left kidney, afterward confirmed by MAG3-radionuclide scan. Diagnosis was also validated by testicular biopsy. No surgery was required. The child is nowadays under observation and at 2-years follow-up he doesn't show any symptom. According to many authors, a conservative treatment of this benign congenital abnormality is suggested as well as serial ultrasonography to monitor the growth of the testicular mass, which in a longest follow-up, could require surgery. Malignant transformation nor infertility have never been described.

Risks and relevance of preputial reconstruction in hypospadia repair.

AIM: To assess the risks related to preputial reconstruction and its relevance for parents of children undergoing hypospadias repair. MATERIALS AND METHODS: One-hundred-and-eighty-six children with distal hypospadias underwent circumcision or preputial reconstruction during the hypospadias repair. The type of procedure was chosen according to anatomical conditions and parents preferences after a careful explanation of possible related risks. Postoperative complications, outcomes, parents' satisfaction were assessed comparing circumcised and uncircumcised patients. RESULTS: No statistical differences in urethral complications were found between the two groups. Urethral or meatal strictures occurred in 11 (6.9%) cases after preputioplasty and in 2 (7.4%) cases after circumcision. Fistulas occurred in 8 (5%) cases after preputial reconstruction and in 1 (3.7%) after circumcision. Preputial reconstruction involved 6 cases (3.7%) of dehiscence and 10 of phimosis (6.2%) as specific complications of this procedure. After a mean follow-up of 3.7 years all the parents stated to be satisfied of the cosmetic results. CONCLUSION: Preputial reconstruction is feasible in many patients with distal hypospadias and it should be considered in accordance with parents' preferences. Parents should be informed that this procedure involves an increased risk of complications in hypospadias repair.

Surgical or conservative treatment of congenital hydronephrosis. Ten years' experience.

BACKGROUND: Controversy exists concerning the ideal management of hydronephrosis diagnosed in the perinatal period. Different opinions depend on the absence of an accurate tool and of well-defined cut-off values for each test. For these reasons we retrospectively evaluated our management protocol. METHODS: Two-hundred and seventy-two patients with single system hydronephrosis were evaluated. Patients with bilateral hydronephrosis or with other renal or ureteral abnormalities were excluded. Diagnosis and grading of hydronephrosis were done by ultrasound. Before 1995, grade II or greater hydronephrosis was also evaluated with diuretic intravenous urography, but in cases studied afterwards, a functional evaluation of the obstruction was reached with well tempered diuretic renogram. Indications for surgery were considered: recurrent urinary tract infections, grade IV hydronephrosis, obstructive drainage pattern and differential renal function less than 40%. Patients managed non-operatively received serial re-evaluation with US-scan, urine test and functional tests if necessary. RESULTS: Hydronephrosis was on the right side in 98 cases (36%), and on the left side in the other 174 (64%). There were 129 grade I hydronephrosis (47%), 46 grade II (17%), 57 grade III (21%), 40 grade IV (15%). Fifty-seven (21%) cases of hydronephrosis underwent surgery: 49 (86%) showing obstructive pattern at functional tests, 40 (70%) presenting a differential renal function less than 40%, 5 (8%) because recurrent urinary tract infections, 40 (70%) affected by grade IV hydronephrosis. No children received nephrectomy. Average postoperative follow-up was 2.8 years: pelvic dilatation improved or remained unchanged but the obstructive pattern at functional tests always disappeared after surgery. The average follow up in the observational group of 163 patients (60%) was 4.1 years. In 149 (91%) pelvic dilatation improved, but in 14 (9%) it remained unchanged. CONCLUSIONS: The ideal management of congenital hydronephrosis is still debated since the natural history of these disease is not still completely understood and there is no accurate tool to assess these renal units. We believe that grade IV hydronephrosis always need surgery as well as those ones with recurrent urinary tract infections, longer drainage time or a differential renal function less than 40%. On the other hand grade I hydronephrosis never need surgery. Mild grade hydronephrosis can be safely managed non-operatively with a meticulous follow-up and undergoing surgery only when signs of deterioration occur.

Long-term follow-up results of vesico-ureteral reflux treated with subureteral collagen injection (SCIN).

BACKGROUND: Endoscopic sub-ureteral injection is at the present a widely used technique for the treatment of vesico-ureteral reflux and it has a good range of efficacy, from 50% up to 90% in relation to different grades. In this paper we report our 1-7 year follow-up results of sub-ureteral collagen injection (SCIN). METHODS: Between 1991 and 1997 we treated with SCIN 129 refluxing ureters in 93 children (60 females and 32 males), mean age 2.1 years (range 3 months-5 years). Fifty-five children had monolateral, but 37 had bilateral reflux. Distribution among different grades was 42 ureters (32.5%) grade 2, 63 (48.8%) grade 3, 24 (18.6%) grade 4. Children were treated with injection of highly purified bovine collagen. In this study all the children underwent radiological follow-up for evaluating the results of treatment with SCIN also in a period of time from 3 to 7 years after endoscopic procedure. RESULTS: After a 1 to 7 years follow-up period we have the following results. In grade 2 we have found absence of reflux in 36 cases (85.7%) after 1 injection and in 38 (90%) after 2 injections. In grade 3, reflux was absent on 46 cases (73%) after 1 injection and in 55 (87.3%) after 2 injections. In grade 4 reflux was cured in 16 (66.6%) after 1 injection and in 18 (75%) after 2 collagen injections, 15% of all units, underwent Cohen's reimplantation. CONCLUSIONS: After 7 years of experience we have concluded that sub-ureteral collagen injection is actually a very good procedure for treatment of mild grade refluxes. We treat these refluxing ureters only when antibiotics prophylaxis is to be prolonged over 6 months with no changes in cystourethrography findings or when recurrent urinary tract infections occur in spite of antibiotics intake. In conclusion, if we evaluate the overall results we see that 73.6% of refluxing ureters have been cured by SCIN, the rate of recurrence is 16.8% and the 15.5% finally underwent Cohen's reimplantation.

[Oxybutinin-desmopressin association in the treatment of primary nocturnal enuresis with diurnal urination disorders]. / Associazione ossibutina-desmopressina nel trattamento dell'enuresi primaria notturna con disturbi minzionali diurni.

BACKGROUND: Since most of the children observed in our Centre present enuresis with voiding disturbance, we carried out a study where these patients were treated with the DDAVP + Oxybutinin association. METHODS: We have treated 89 children with enuresis and voiding disturbances (urge incontinence, voiding urgency, urinated > 7 times a day), administering a drugs combination of desmopressin (20 micrograms/daily) and oxybutinin (0.3-0.6 mg/kg/bid or tid) for a variable period, depending on response to the treatment. RESULTS: The results demonstrate the efficacy of this association: we have observed a reduction in average bed wetting nights from 23.4 nights/month to 6.4 wet nights after 1 month, to 3.8 ad 2.9 respectively after 3 and 6 months from the beginning. Moreover we obtained a recovery of all daily voiding disturbances after 3 months. Fifty percent of children were cured after 4 months of therapy and finally 93.2% recovered at 6 months. On the other hand, 2 children were no-responders to the therapy even after 9 months of combined drugs administration. CONCLUSIONS: Based on these results we can affirm that children with nocturnal enuresis and voiding disturbance can be treated with this combined therapy. Actually, the reduction of urinary output and thus lower bladder filling, due to the desmopressin, decreases the onset of uninhibited bladder contractions and enhances oxybutinin activity.