Reversal of diastolic plateau in partial testicular torsion.

Testicular torsion is a urologic emergency. The ability of color and power Doppler sonography to diagnose partial testicular torsion definitively remains uncertain. We present a case in which color Doppler findings were indeterminate and the diagnosis of partial testicular torsion was made on the basis of spectral waveform analysis. The characteristic findings in the spectral waveform were asymmetry between the 2 testes, with a higher intratesticular resistance index on the affected side, and reversal of the diastolic plateau on the affected side.

A noninvasive test for vesico-ureteric reflux in children.

OBJECTIVE: To report the development and testing of a device for the noninvasive diagnosis of vesico-ureteric reflux (VUR) which avoids the need for urethral catheterization (currently required to reliably determine the presence of VUR), and which thus avoids the anxiety of parents and patients that causes many families to refuse such evaluation. PATIENTS AND METHODS: Fifty-four children (49 girls and five boys, mean age 7.2 years, range 4-14) previously evaluated as having VUR volunteered to participate; no child was symptomatic at the time of the study. Refluxing units were known to be present by voiding cysto-urethrography (within 1 year, mean 7 months) in 45 and absent in 16. The device developed acquires electronically processed acoustic signals from the child during an observed urination. The signals are then analysed 'off-line' to determine the presence or absence of VUR. The initial preparation for the test included: (i) a full bladder [at least 0.80 x ((2 + age) x 30 mL)] measured by ultrasonography; and (ii) localization of the pelvi-ureteric junction by ultrasonography to accurately place the device's sensors on the child's back. The children were then positioned at a commode after placing the sensors; the recording was started and continued until voiding occurred. The children were tested with the recording and analysis team unaware of the presence and/or degree of VUR. The first 47 studies were single-kidney examinations and the remaining seven included simultaneous monitoring of both kidneys. RESULTS: Sixty-one renal units were assessed and interpretable signals were obtained from 54 (89%). There were seven episodes of 'system failure' when no interpretable data were obtained. One unit with no VUR had a 'reflux' signal; in four kidneys, spontaneous (two) and postsurgical (two) resolution of reflux was predicted by the testing and subsequently verified by cyclic radionuclide cystography. CONCLUSIONS: This noninvasive diagnostic technique detected VUR in 35 of 37 refluxing units and verified no reflux in 16 of 17 units without VUR. Further refinements may allow this technology to be used in all children with suspected VUR.

Laparoscopy for the evaluation and management of the nonpalpable testicle.

OBJECTIVE: To assess the usefulness of laparoscopy for the diagnosis and treatment of the nonpalpable testicle and to evaluate the results of laparoscopic orchidopexy. METHODS: We retrospectively reviewed the charts of 91 laparoscopies performed over a period of 4 years. We reviewed the following parameters: findings, complications, patency of the processus vaginalis, appearance of the cord structures, and the success of the different procedures performed for the intra-abdominal testicle. RESULTS: Fourteen patients had bilateral and 77 unilateral nonpalpable testicles. The mean age of the patients was 39.5 +/- 50.8 months. There were three laparoscopic complications (3.2%) one of which was a major bowel laceration. Laparoscopy defined the intra-abdominal anatomy accurately in 90 of the 91 cases Of the 26 intra-abdominal testicles above the ring, a one-stage laparoscopic orchidopexy was performed in five and a single-stage standard orchidopexy in seven. All of these testicles remain viable and are in good position. Eight patients underwent a staged Fowler-Stephens orchidopexy with laparoscopic clipping of the spermatic vessels as the first stage. Of these, a second-stage open orchidopexy was performed in five and a laparoscopic orchidopexy in three. Testicular atrophy occurred in two of the patients who underwent the second-stage open orchidopexy. Three one-stage Fowler-Stephens orchidopexies were performed with testicular atrophy occurring in two of these testicles. Laparoscopic orchiectomy was performed on two patients. CONCLUSIONS: Laparoscopy is a valuable tool in the diagnosis and treatment of the nonpalpable testicle. Laparoscopic orchidopexy may decrease the rate of testicular atrophy since most of these can be performed laparoscopically in one stage, thus preserving the vascular supply.

Detrusorrhaphy for repair of unilateral vesicoureteral reflux: report of 76 patients using a modified technique.

OBJECTIVE: To present our results for repair of unilateral vesicoureteral reflux in 76 children using a modified technique of detrusorrhaphy. METHODS: A retrospective chart review was performed for 76 children who underwent repair of unilateral vesicoureteral reflux by a modified technique of detrusorrhaphy. Of the 76 refluxing ureters, 12 were associated with historically refluxing contralateral ureters. In addition, 72/76 were grades II to IV; 4/76 grade V; three had a paraureteral diverticulum; four completely duplicated collecting systems; and two had associated ureteroceles. The surgical technique was modified to preserve both the obliterated umbilical artery and superior vesical pedicle and to minimize trigonal distortion through dissection lateral to the trigone in a direct path to the bladder neck. RESULTS: Seventy-five of 76 ureters were successfully repaired (99%). The remaining ureter showed initial improvement to grade I reflux and spontaneous resolution by 1 year. Obstruction did not occur. Three episodes of "new onset" contralateral vesicoureteral reflux were noted postoperatively. This represents a substantial decrease in incidence (3.9%) when compared with previously reported series (18%). CONCLUSION: Detrusorrhaphy is a reasonable treatment of unilateral vesicoureteral reflux with utility in the full range of anatomic associations. This approach is also associated with a lower incidence of new onset, contralateral reflux when compared with intravesical surgery.

Clean intermittent catheterization in boys using the LoFric catheter.

PURPOSE: We compared a recently developed hydrophilic catheter to the standard polyethylene catheter in regard to hematuria, infection and patient satisfaction. MATERIALS AND METHODS: A hydrophilic LoFric or standard Mentor catheter was assigned at random to 17 and 16 boys, respectively, who were skilled in intermittent self-catheterization. They were evaluated by weekly urinalysis and a questionnaire. RESULTS: Significantly fewer episodes of microscopic hematuria occurred in the LoFric than Mentor catheter group (9 episodes in 6 subjects versus 19 episodes in 11, p < 0.05). There were also fewer episodes of bacteriuria in the LoFric group but the difference was not statistically significant. Mean scores plus or minus standard deviation on a visual analogue scale with 0 equal to most and 10 equal to least favorable were LoFric 3.3 +/- 2.8 versus Mentor 4.9 +/- 2.7 for catheter convenience and 2.7 +/- 2.4 versus 4.2 +/- 2.6 for insertion comfort, significantly favoring the LoFric group (p < 0.05 for both). Of the 16 LoFric subjects 13 preferred to continue its use, particularly those with a history of urethral trauma or sphincteric spasm. CONCLUSIONS: In boys the LoFric catheter appears to cause less trauma. Although it is not reusable and is more expensive than the standard catheter, satisfaction is higher with the LoFric device and for select patients it has significant advantages.

Efficacy of retrograde endopyelotomy in children.

PURPOSE: Endopyelotomy has been performed extensively in adults for the treatment of ureteropelvic junction obstruction. To determine its applicability to the pediatric population we reviewed our experience with retrograde endopyelotomy in children. MATERIALS AND METHODS: Eight children 4 to 15 years old were treated with retrograde endopyelotomy and results were compared to those of a concurrent group of 8 treated with open pyeloureteroplasty. RESULTS: Retrograde endopyelotomy was done in all of our patients with lower ureteral dilatation (as an adjunct measure in 5). Seven patients had symptomatic and radiographic improvement. The patient in whom the procedure failed had a crossing lower pole vessel. Postoperative analgesia, length of hospitalization and cost were lower in the endopyelotomy group. CONCLUSIONS: Retrograde endopyelotomy is feasible in children older than age 4 years and it results in reduced morbidity. The success rate is high but open surgery remains the standard, particularly when a crossing lower pole vessel is identified preoperatively.

The effect of prepubertal androgen exposure on adult penile length.

PURPOSE: Recent studies in the rat suggest that early exposure to exogenous testosterone accelerates the loss of androgen receptors and compromises eventual penile length. To determine whether this is true in men we measured adult penile length of patients treated in childhood for sexual precocity. MATERIALS AND METHODS: We examined 21 men with sexual precocity due to true precocious puberty (12) or congenital adrenal hyperplasia (9) who had been followed at our institution since childhood. Penile lengths were compared with data from normal men. RESULTS: Mean stretched penile length plus or minus standard deviation was 12.7 +/- 2.6 cm. in all patients, 12.1 +/- 2.6 cm. in those with true precocious puberty and 13.6 +/- 1.6 cm. in those with congenital adrenal hyperplasia. These lengths were not significantly different from those of normal men (12.4 +/- 2.7 cm.). CONCLUSIONS: In contrast to findings in rats, exposure to endogenous testosterone during gestation and/or childhood does not reduce adult penile length in men. Thus, the use of testosterone to treat childhood genitourinary anomalies would likely not compromise mature penile size.

Exogenous endothelin-1 causes renal vasodilation in the fetal lamb.

PURPOSE: Endothelin-1 is known to be a potent vasoconstrictor. We investigated the effects and mechanisms of action of endothelin-1 and its receptors in regulating renal vascular tone in the fetal lamb. MATERIALS AND METHODS: We observed the in vivo effects of endothelin-1, an endothelin-b receptor agonist (4-alanine-endothelin-1), endothelin-a receptor antagonists (BQ-610 and BQ-123), and the inhibition of prostaglandin and nitric oxide synthesis on the response of the renal circulation to endothelin-1 in a chronic preparation in third trimester fetal lambs. RESULTS: After injection of 250 ng./kg. endothelin-1 into the descending aorta proximal to the renal arteries in 8 fetal animals, renal blood flow increased (4.4 +/- 0.7 ml. per minute per kg., p < 0.001 versus vehicle), as did mean arterial blood pressure (3.0 +/- 0.3 mm. Hg,p < 0.001 versus vehicle). Calculated renal vascular resistance decreased (-1.1 +/- 0.2 mm. Hg per minute per kg./ml., p < 0.001 versus vehicle). After injection of 1,725 ng./kg. 4-alanine-endothelin-1 in 5 animals renal blood flow increased (3.8 +/- 0.4 ml. per minute per kg., p < 0.05 versus vehicle) and mean arterial blood pressure was unchanged (1.6 +/- 1.7 mm. Hg). Calculated renal vascular resistance decreased (-0.8 +/- 0.2 mm. Hg per minute per kg./ml., p < 0.05 versus vehicle). After injection of 0.5 mg./kg. BQ-610 in 6 animals renal blood flow increased (2.3 +/- 0.7 ml. per minute per kg., p < 0.05) and mean arterial blood pressure decreased (-2.7 +/- 0.3 mm. Hg, p < 0.05 versus vehicle). Calculated renal vascular resistance decreased but this difference was not statistically significant (-0.7 +/- 0.3 mm. Hg per minute per kg./ml., p < 0.07). A dose of 1 mg./kg. BQ-123 in 2 animals decreased renal vascular resistance markedly. Infusion of a prostaglandin synthesis inhibitor (1 mg./kg. per minute meclofenamic acid) did not alter the decrease in renal vascular resistance after endothelin-1 (-0.7 +/- 0.4 mm. Hg per minute per kg./ml). In contrast, during infusion of a nitric oxide synthesis inhibitor (1.5 mg./kg. per minute N-omega-nitro-L-arginine) endothelin-1 increased renal vascular resistance (1.2 +/- 0.2 mm. Hg per minute per kg./ml., p < 0.001). CONCLUSIONS: Endothelin-1 is a vasodilator in the fetal renal circulation, which acts primarily via endothelin-b receptors. Ongoing activity of endothelin-a receptors contributes to renal vascular tone in fetal lambs. The vasodilatory effects of endothelin-1 in the fetal lamb renal circulation are mediated via the nitric oxide system and not via prostanoids.

Lower urinary tract function in ambulatory children with spina bifida.

OBJECTIVE: To investigate lower urinary tract function in ambulatory children with myelomeningocele. PATIENTS AND METHODS: The urological course of 45 children with myelomeningocele who walked either independently (19 children) or with ankle-foot orthotics (26 children) was reviewed. Follow-up ranged from 9 months to 13.5 years (mean 4.75 years). RESULTS: A normal pattern of voiding was observed both clinically and during urodynamic evaluation in only three of the 45 children, with the remainder displaying neurogenic lower urinary tract dysfunction. The independent walkers and those with orthotics did not differ in the spectrum of lower urinary tract dysfunction or other variables. Those patients with persistent incontinence underwent an initial urodynamic evaluation when older (mean 3.7 years versus 6.4 weeks in those who were continent). CONCLUSION: Ambulatory children with myelomeningocele suffer the full spectrum of lower urinary tract dysfunction. Given the potential danger of untreated lower urinary tract dysfunction, ambulatory children with myelomeningocele should receive the same diagnostic and therapeutic attention as their peers with more overt neurological deficits.

The prune-belly syndrome: current insights.

The prune-belly syndrome comprises a constellation of well-established physical findings, yet the cause and management remain controversial. This review focuses on the current understanding of its pathogenesis and characterizes the fetal and neonatal diagnosis and management. Other associated anomalies are discussed to understand better the factors affecting treatment and prognosis as these patients grow into childhood and beyond.

Contradictory renal function measured with mercaptoacetyltriglycine diuretic renography in unilateral hydronephrosis.

PURPOSE: We studied apparently supranormal renal function in hydronephrotic kidneys, as measured by 99mtechnetium mercaptoacetyltriglycine renography. MATERIALS AND METHODS: We retrospectively reviewed the clinical history, ultrasonography and renography of 29 children. RESULTS: Of the 29 children 7 had greater than 50% relative function in the hydronephrotic kidney. This finding was independent of patient age, gender, degree of hydronephrosis or obstructive pattern. Of these 7 cases 6 occurred on the right side (p < 0.05 versus a large registry). CONCLUSIONS: In most cases supranormal renal function is caused by a technical problem, likely the inadequate background subtraction of mercaptoacetyltriglycine in the liver.

Renal preservation despite 35 days of partial bladder obstruction in the fetal lamb.

To determine whether the increase in renal blood flow and preservation of renal function that we demonstrated after 10 days of chronic partial bladder obstruction in the third trimester fetal lamb also occur after earlier longer obstruction, we modified our preparation and studied the effects of 35 days of obstruction begun during the second trimester. Partial bladder obstruction was created in 10 fetal lambs at 90 days of gestation (term equals 147 days). At repeat surgical intervention 28 days later vascular catheters and a left renal artery flow transducer were placed, and catheters were externalized. We then studied renal blood flow and function at gestational ages 120 days and 125 days after 30 days and 35 days of obstruction, respectively. Tissue was obtained for histology at the time of sacrifice. Eight control fetal lambs without obstruction were studied in a similar way. Bilateral hydroureteronephrosis was noted in all fetal lambs after partial obstruction, whereas the kidneys and bladders of the control animals had a normal appearance. Renal blood flow was higher in the obstructed fetal lambs than in controls (20.2 +/- 4.9 versus 10.2 +/- 0.9 ml. per minute per kg., p < 0.05 after 30 days and 17.1 +/- 2.7 versus 9.7 +/- 0.9 per minute per kg., p < 0.05 after 35 days). There was no evidence of decreased renal function by any parameter and, in fact, glomerular filtration rate and urine volume were increased after 30 days of obstruction (1.59 +/- 0.32 versus 0.69 +/- 0.07 ml. per minute per kg., p < 0.05 and 15.7 +/- 4.3 versus 5.2 +/- 0.8 ml. per hour per kg., p < 0.05, respectively). Histological studies demonstrated normal architecture of the kidneys but thinned cortex. We conclude that the physiological responses of the fetus are such that partial lower urinary tract obstruction in our preparation results in a prolonged increase in renal blood flow and preservation of renal function.

The physiology of gastrocystoplasty: once a stomach, always a stomach.

To determine the physiology of acid secretion after gastrocystoplasty with the body of the stomach we performed a prospective standardized 3-day study in 13 children (median age 12.5 years) who had undergone bladder augmentation/replacement (median postoperative period 2 years). Urinary pH and titratable acid, and serum gastrin levels were measured after gastric distention with a meal and bladder distention with urethral filling at baseline and after medication with a histamine-2 receptor antagonist or an anticholinergic agent. Five children underwent cystoscopy and biopsy of the gastric and native segments of the gastrocystoplasty. In the fasting state pH was neutral, there was no titratable acid in the urine and serum gastrin level was normal in all cases. After a meal urinary acid secretion and serum gastrin level increased markedly. After each medication half of the patients demonstrated marked inhibition of urinary acid secretion after a meal while response was partial in the remainder. In none of the patients was there significant alteration in the pattern of gastrin secretion. Bladder distention did not result in urinary acid secretion or gastrin secretion. The cystoscopic and histological appearance of the native bladder and stomach segment of the gastrocystoplasty in the 5 patients was normal. We conclude that the gastric body segment used in gastrocystoplasty continues to secrete acid as though it were part of the stomach. The secretion of acid in the urine can be decreased with histamine-2 receptor antagonist or anticholinergic medication.

Urine concentration and enuresis in healthy preschool children.

OBJECTIVES: To determine whether children concentrate their urine overnight and to assess the correlation between specific gravity of a first morning urine specimen and the results of a questionnaire concerning bedwetting, voiding habits, and continence in 47 healthy children aged 3 to 6 years. DESIGN: A prospective observer-blinded consecutive sample. SETTING: Two San Francisco, Calif., preschools. PARTICIPANTS: Forty-seven children attending preschool during the study period. MEASUREMENTS/MAIN RESULTS: Forty of 47 children had a urine specific gravity greater than 1.020. None of these children wet the bed during this study, although four (11%) of 36 had a history of bedwetting. Furthermore, seven children with a urine specific gravity of 1.015 or lower had a history of bedwetting and wet the bed during this study. A voiding frequency of six or more times per day, by history, was associated with a 3:1 relative risk of bedwetting but did not segregate children with primary enuresis from those with secondary enuresis. CONCLUSIONS: Our results indicate that healthy children aged 3 to 6 years are able to concentrate their urine. In addition, urine specific gravity was an accurate predictor of the presence of nocturnal enuresis in this group of children. Our results suggest that a specific gravity of the first morning urine specimen should be correlated with appropriate history before extensive diagnostic evaluation or empiric therapy is performed in children with nocturnal enuresis.

Fetal lower urinary tract physiology: in vivo studies.

Fetal lower urinary tract function is under continuous maturation throughout gestation and is an integrated neurophysiologic event by late gestation. Preliminary in vivo study suggests that peripheral and central nervous system regulation of micturition occurs in utero, and that these events can be modulated pharmacologically and through external stimulation. Normal bladder function in utero is essential to normal development of the entire fetus, and in utero modulation of bladder dysfunction may be feasible as our understanding and diagnostic acumen increase.

Urodynamic and clinical follow-up of 28 children after gastrocystoplasty.

OBJECTIVES: To determine the efficacy of gastrocystoplasty in creating a large and compliant urinary reservoir. PATIENTS AND METHODS: Twenty-eight children (14 boys, 14 girls), with a median age of 9 years (range 4-17), were evaluated before and for a median of 2 years and 5 months after gastrocystoplasty. Evaluation included urodynamic and renal function studies and a survey of their post-operative complications and their sense of well-being. Renal function was assessed by ultrasound and serum creatinine, and electrolytes were measured. RESULTS: After gastrocystoplasty bladder size increased, compliance improved, hydronephrosis decreased or was stable, and renal function remained stable. There were minimal complications and the children's subjective impression of their well-being was markedly improved. CONCLUSION: Gastrocystoplasty, using our surgical technique, is a reliable method of creating a large and compliant urinary reservoir. Advantages include the absence of clinical urinary tract infections, the absence of mucus and the preservation of renal function. Complications, such as haematuria, dysuria and hypochloraemic alkalosis, might be avoided by excluding the antrum from the gastrocystoplasty, maintaining the child on a normal salt-containing diet, employing catheterization or buffering the urine in children with normal urethral sensation.

Pediatric ureteropelvic junction obstruction treated with retrograde endopyelotomy.

OBJECTIVES: To determine the feasibility of retrograde endopyelotomy in the management of pediatric ureteropelvic junction (UPJ) obstruction. METHODS: We treated 2 boys aged 4 and 6 years with the Acucise endopyelotomy device for symptomatic ureteropelvic junction obstruction. The Acucise device was placed over a Lunderquist guide wire with fluoroscopic guidance only and routine Double J catheters were left in situ for 6 weeks after the procedure. The morbidity of the treatment and the short-term outcome were assessed. RESULTS: There were no acute complications and short-term follow-up results were satisfactory as determined by intravenous urography and diuretic renography. CONCLUSIONS: Ureteropelvic junction obstruction in children may be treated by retrograde endopyelotomy with the Acucise device. The principal potential advantage of this procedure is reduced morbidity. Our findings suggest that further evaluation is warranted.

Role of nitric oxide in fetal lower urinary tract function.

We studied the role of nitric oxide (NO) in normal function of the lower urinary tract in fetal lambs. Fetal surgery was performed in pregnant ewes at 118 days' gestation (term 145-days) to place arterial, venous, and double-lumen urachal catheters. Five animals had a catheter secured in the distal urethra (to measure voided volume), and six underwent ligation of the urethra. Urodynamic studies were performed via the urachal catheter under baseline conditions, during systemic blockade of NO synthesis with N omega-nitro-L-arginine, and with systemic NO stimulation by L-arginine 48 hours postoperatively. Nitric oxide blockade caused an 88% mean increase in bladder capacity (volume to initiation of voiding) (p < 0.001) and a 5.8-fold increase in mean postvoid residual volume (p < 0.0001) despite normal maximal bladder pressures, suggesting inadequate sphincteric relaxation. Qualitatively, NO inhibition increased the presence of low-level bladder contractions and caused a trend toward decreased bladder compliance. Increase of NO substrate by L-arginine infusion restored baseline findings if performed after N omega-nitro-L-arginine. Stimulation of NO by L-arginine infusion caused continuous efflux of the infusate secondary to a persistently open sphincter. In conclusion, NO is active in the function of the lower urinary tract in the fetal lamb and appears to influence both sphincter and detrusor activity.