Secondary bladder neck obstruction in patients with urethral valves: Treatment with phenoxybenzamine

Efficacy and safety of tamsulosin as a medical expulsive therapy for stones in children

OBJECTIVES

To evaluate the efficacy of tamsulosin for promoting ureteric stone expulsion in children, based on the confirmed efficacy of tamsulosin as a medical expulsive therapy in adults.

PATIENTS AND METHODS

From February 2010 to July 2013, 67 children presenting with a distal ureteric stone of <1 cm as assessed on unenhanced computed tomography were included in the study. The patients were randomised into two groups, with group 1 (33 patients) receiving tamsulosin 0.4 mg and ibuprofen, and group 2 (34) receiving ibuprofen only. They were followed up for 4 weeks. Endoscopic intervention was indicated for patients with uncontrolled pain, recurrent urinary tract infection, hypersensitivity to tamsulosin and failure of stone passage after 4 weeks of conservative treatment.

RESULTS

Sixty-three patients completed the study. There were no statistically significant differences between the groups in patient age, body weight and stone size, the mean (SD) of which was 6.52 (1.8) mm in group 1 vs. 6.47 (1.79) mm in group 2 (P = 0.9). The mean (SD) time to stone expulsion in group 1 was 7.7 (1.9) days, vs. 18 (1.73) days in group 2 (P < 0.001). The analgesic requirement (mean number of ketorolac injections) in group 1 was significantly less than in group 2, at 0.55 (0.8) vs. 1.8 (1.6) (P < 0.001). The stone-free rate was 87% in group 1 and 63% in group 2 (P = 0.025).

CONCLUSIONS

Tamsulosin used as a medical expulsive therapy for children with ureteric stones is safe and effective, as it facilitates spontaneous expulsion of the stone.

Posterior urethral valve: Prognostic factors and renal outcome

OBJECTIVE

The aim was to study the outcome of posterior urethral valve (PUV) cases treated by stepladder protocol and the prognostic factors affecting the outcome.

MATERIALS AND METHODS

Hospital records of all PUV patients treated by stepladder protocol between January 1992 and December 2013 were reviewed. The studied parameters were: Age at presentation, serum creatinine, types of surgical intervention, vesicoureteral reflux (VUR) on initial voiding cystourethrogram (VCUG), renal cortical scars, plasma renin activity (PRA), and glomerular filtration rate (GFR).

RESULTS

Of 396 PUV patients treated during the study period, 152 satisfied study criteria. The age at presentation ranged from 2 days to 15 years (mean 31.3 months). The mean follow-up period was 5 years (range: 2-18 years). Primary endoscopic valve ablation was the most common initial procedure. Chronic renal failure was seen in 42.7% patients at the last follow-up. Serum creatinine at presentation, initial PRA levels, initial GFR, and PRA levels at last follow-up were significant predictors of final renal outcome. Age at presentation (<1 vs. >1 year), presence/absence of VUR on initial VCUG and renal cortical scars had no significant correlation with ultimate renal function.

CONCLUSION

Our study confirms the high prognostic significance of initial serum creatinine, PRA levels and GFR in cases with PUV. PRA also holds promise in long-term follow-up of these patients as a marker of progressive renal damage.

Primary bladder neck obstruction in men, women, and children

The understanding of the presentation, diagnosis, and treatment of primary bladder neck obstruction (PBNO) has evolved over the last 20 years. It was first identified 70 years ago, but the etiology is still unclear. There are multiple theories as to the etiology, including muscular and neurological dysfunction and fibrosis. Over the years, many voiding parameters and cut points and nomograms have been presented for diagnosis of nonneurogenic functional bladder outlet obstruction in young men. Until recently, there was a paucity of data on PBNO in women and children. Videourodynamics provide an accurate diagnosis of PBNO but for some patients are an invasive option. Treatments vary from watchful waiting to alpha-blockade to surgery, depending on the severity of symptoms, urodynamic findings, and response to medical therapy. This paper reviews the theories on etiology, incidence, presentation, and diagnostic evaluation, and briefly discusses treatment options for PBNO.

Effect of choline ester analogues, noradrenaline and nifedipine on normal and hypertrophied human urinary bladder detrusor muscle

1. Acetylcholine, bethanechol, carbachol and propionylcholine were all agonists of normal human detrusor smooth muscle. The order of potency was found to be carbachol > acetylcholine > bethanachol > propionylcholine. 2. In hypertrophied detrusor smooth muscle carbachol was more potent than acetylcholine, but hypertrophied detrusor preparations were less sensitive to carbachol than normal detrusor smooth muscle. 3. Noradrenaline had no direct effect on either normal or hypertrophied detrusor muscle, but it had a reversible inhibitory effect on the spontaneous contractile activity of normal detrusor preparations. Hypertrophied detrusor preparations usually lacked such spontaneous activity. 4. In calcium-free saline, agonist-induced responses of both normal and hypertrophied detrusor muscle were dramatically reduced indicating that choline ester activity in the muscles was strongly dependent upon extracellular calcium. 5. Nifedipine at 10(-5) mol l-1 inhibited acetylcholine responses and K(+)-induced contractures of both normal and hypertrophied detrusor muscles. Acetylcholine-induced responses of normal detrusor preparations were much more sensitive to inhibition by nifedipine than were the responses of hypertrophied detrusor muscle. 6. The properties and densities of both the muscarinic cholinoreceptors and calcium channels appear to have been altered by the hypertrophic response secondary to benign prostatic hyperplasia.

Evolution of upper urinary tract and renal function in patients with posterior urethral valves

From January 1972 to June 1993, 166 patients with posterior urethral valves (PUV) were treated in our surgical department, 59 with a milder form of PUV (upper urinary tract [UUT] complication rate 29%) and 107 with a severer form (UUT complication rate 96.3%). Only the latter group was studied for long-term (mean 9.3 years) evaluation of the UUT and renal function. A temporary vesicostomy was the primary treatment in 25 patients. Indications for temporary diversion were very young age and/or low birth weight, severe and bilateral UUT complications, and severe renal damage. All the other patients were treated by primary endoscopic valve fulguration. After removal of the lower urinary tract obstruction, vesicorenal reflux (VRR) resolved spontaneously or was ameliorated in 59.2% of the renal units. Spontaneous normalization or evident amelioration were found at long-term follow-up in nearly 70% of dilated, non-refluxing ureters. Ureteral reimplantation was performed on 41 of the 202 dilated or refluxing ureters (surgical rate 20.3%). The surgical failure rate requiring reoperation was 5% (2/41). The prerequisite for successful reimplantation was a large-capacity, stable, and compliant bladder. Ten nephroureterectomies were carried out for unilateral, massive VRR and renal dysplasia; 1 late nephrectomy was performed for arterial hypertension. The evolution of renal function showed statistically significant overall improvement, which was more evident in patients diagnosed and treated in the 1st month of life (P = 0.000) than in those treated between 1 and 12 months (P = 0.004) or after 1 year of age (P = 0.025). Renal function considerably improved in the vesicostomy group (P = 0.000). Thirteen patients (12.4%) are now either dead (2) or have end-stage renal disease (6) or chronic renal insufficiency evolving toward end-stage renal disease (5); 5 of these 13 were treated by vesicostomy in the first days or months of life, and at presentation the glomerular filtration rate (GFR) was less than 25 ml/min . 1.73 m(2). Determination of basic GFR and, even more, functional renal reserve is relevant in predicting the long-term evolution. In the author's opinion, vesicostomy is the procedure of choice in very ill newborns or infants. Aggressive management with early surgical reconstruction is rarely justified, because frequently UUT complications resolve spontaneously or clearly improve, and their surgical treatment has limited and very precise indications.

Evolution of urodynamic patterns in posterior urethral valves

A retrospective, long-term urodynamic study was performed in order to follow the evolution of the urodynamic patterns in 55 unselected patients previously affected by posterior urethral valves (PUV). The mean maximum cystometric capacity (MCC) values progressively increased over time and, on long-term follow-up, were just above 2 standard deviations (SD). The mean compliance values were clearly reduced in the first urodynamic studies after valve ablation, and only after a mean of 5 years follow-up did they approach the lower limits of normal. The small compliance and capacity (SCC) group showed two trends of evolution: a more numerous subgroup tended toward progressive normalization while a second subgroup (<20%) showed mean compliance values below normal limits, with reduced (-2 SD) MCC persisting at long-term follow-up. The number of patients in this group decreased over time. In contrast, we were able to show a significant increase in patients with myogenic failure. In this group scheduled voiding using the Valsava maneuver in conjunction with a regimen of double or triple micturition was usually succesful in modifying the course, normalizing MCC, reducing residual urine, and also eliminating incontinence. Finally, initial urodynamic investigations in the fulguration and vesicostomy groups showed a much higher percentage of SCC bladders in the latter group (83.5% vs. 35%). However, at long-term examinations the urodynamic parameters were nearly identical in both groups, showing that temporary bladder defunctionalization does bot adversely affect future detrusor activity. No direct relationship between urodynamic abnormalities and renal insufficiency could be shown, however, the majority of patients with reduced glomerular filtration rates still showed urodynamic dysfunction at long-term follow-up. In the authors' opinion, serial urodynamic investigations in association with serial evaluation of the evolution of upper urinary tract and renal function are mandatory for correct PUV management and provide useful guidelines for avoiding incorrect treatment and obtaining better long-term results.

Urodynamic evaluation of dysfunctional bladder neck obstruction in men

Dysfunctional bladder neck obstruction in young men has received increasing interest in recent years. The urodynamic characteristics of this disorder include elevated voiding pressure, normal reflex relaxation of the urethral rhabdosphincter, increased pressure gradient between the membranous urethra and the bladder, and inadequate radiographic bladder neck opening during detrusor activity. The functional changes occurring at the internal sphincter in 3 patients with dysfunctional bladder neck obstruction are described herein. It is demonstrated that the obstruction may result from either an active dyssynergic bladder neck contraction or failure of bladder neck relaxation. While the pathophysiology of dysfunctional bladder neck obstruction is uncertain possible mechanisms are discussed.

The bladder in boys with posterior urethral valves: a urodynamic assessment

Urodynamic evaluation was performed on 8 of 62 boys (13 per cent) with persistent voiding difficulties after fulguration of posterior urethral valves. All had varying degrees of incontinence when evaluated. The striated muscle component of the external urethral sphincter was intact in each child. Five different types of bladder function were noted in the 8 children. Three boys had had a prior Y-V plasty of the bladder neck to improve upper and lower urinary tract emptying, which may have contributed to the subsequent incontinence. One additional boy had significant bladder neck obstruction requiring a unilateral bladder neck incision to improve voiding. Appropriate treatment plans were instituted based on the urodynamic findings of the bladder, bladder neck and external sphincter areas, and 6 of the 8 children are now completely continent.

Disorders of micturition: neuropharmacologic basis and results of drug therapy

The clinical use of various pharmacologic agents in problems of micturition is based on the new concepts of intrinsic urethrovesical innervation, presence and regional predominance of autonomic neuroreceptors, and experimental evidence of the effects of various drugs on the bladder and the urethra. A new concept, relating to the processes that control bladder filling and emptying, is coming into being and replacing the traditional concept based on anatomic grounds alone. On the basis of the published data, and from personal experience both experimental and clinical, pharmacologic agents singly or in combination can be effectively and safely used in various problems of micturition such as incontinence (enuresis, stress incontinence in women, postprostatectomy, urgency incontinence), and functional outflow obstruction caused by neurologic or non-neurologic disease processes.