Nifedipine and methylprednisolone in facilitating ureteral stone passage: a randomized, double-blind, placebo-controlled study

Celecoxib in the management of acute renal colic: a randomized controlled clinical trial

OBJECTIVES

To evaluate the efficacy of celecoxib as an analgesic and medical expulsive agent in acute renal colic.

METHODS

A prospective randomized double-blind study was conducted on patients presenting with an obstructing ureteral calculus < 10 mm in largest diameter. Patients were randomized to 400 mg of celecoxib, followed by 200 mg every 12 hours for 10 days, or to placebo. Patients with a solitary kidney, renal insufficiency (CR > 1.8), urinary tract infection, or significant cardiovascular disease were excluded.

RESULTS

A total of 57 patients provided consent of which 53 completed the study. Four patients were excluded from the analysis because of stone passage or withdrawal of consent before the first dose of study medication. No significant difference was noted in the spontaneous stone passage rate (celecoxib 55.2%, placebo 54.2%) and between celecoxib and placebo with regard to days to stone passage (7.0 vs 9.0, P = .6) or size of stone passed (3.9 vs 4.6 mm, P = .18). No significant difference was noted in pain analog scores (2.6 vs 3.5, P = .71) or narcotic doses (13.2 vs 13.6, P = .74). Furthermore, a 25% decrease in narcotic use (or 19 mg based on placebo mean) was outside the 80% one-sided confidence interval for the change in mean narcotic use between the 2 groups. Thus, it is unlikely (< 20%) that we missed a clinically significant beneficial effect of celecoxib on narcotic consumption because of sample size.

CONCLUSIONS

Celecoxib does not facilitate stone passage or decrease narcotic requirements in patients with acute renal colic.

Recent advances in management of ureteral calculi

The management of patients with urinary tract stone disease has changed dramatically over recent years, with current treatment modalities focused on their minimal invasiveness. In this article we will discuss the recent advances in the field of urolithiasis management, with a focus on medical expulsive therapy, extra-corporeal shockwave lithotripsy and ureteroscopy.

Medical therapy to facilitate the passage of stones: what is the evidence?

CONTEXT

Medical expulsive therapy (MET) for urolithiasis has gained increasing attention in the last years. It has been suggested that the administration of alpha-adrenoreceptor antagonists (alpha-blockers) or calcium channel blockers augments stone expulsion rates and reduces colic events.

OBJECTIVE

To evaluate the efficacy and safety of MET with alpha-blockers and calcium channel blockers for upper urinary tract stones with and without prior extracorporeal shock wave lithotripsy (ESWL).

EVIDENCE ACQUISITION

A systematic review of the literature was performed in Medline, Embase, the Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews searched through 31 December 2008 without time limit. Efficacy and safety end points were evaluated in 47 randomised, controlled trials assessing the role of MET. Meta-analysis was conducted using Review Manager (RevMan) v.5.0 (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark).

EVIDENCE SYNTHESIS

Pooling of alpha-blocker and calcium channel blocker studies demonstrated a higher and faster expulsion rate compared to a control group (risk ratio [RR]: 1.45 vs 1.49; 95% confidence interval [CI]: 1.34-1.57 vs 1.33-1.66). Similar results have been obtained after ESWL (RR: 1.29 vs 1.57; 95% CI: 1.16-1.43 vs 1.21-2.04). Additionally, lower analgesic requirements, fewer colic episodes, and fewer hospitalisations were observed within treatment groups.

CONCLUSIONS

Pooled analyses suggest that MET with alpha-blockers or calcium channel blockers augments stone expulsion rates, reduces the time to stone expulsion, and lowers analgesia requirements for ureteral stones with and without ESWL for stones < or = 10 mm. There is some evidence that a combination of alpha-blockers and corticosteroids might be more effective than treatment with alpha-blockers alone. Renal stones after ESWL also seem to profit from MET. The vast majority of randomised studies incorporated into the present systematic review are small, single-centre studies, limiting the strength of our conclusions. Therefore, multicentre, randomised, placebo-controlled trials are needed.

Medical therapy of stone disease: from prevention to promotion of passage options

Medical therapy has been used for many years in the prevention of urinary stones. Medications directed at correcting urinary metabolic abnormalities responsible for promoting stone formation include thiazide diuretics, citrate salts, and allopurinol. All have proven to be efficacious. In addition, intake of citrate-rich juices, such as lemonade, may help to reduce urinary stone formation. More recently, there has been increasing interest in and use of medical therapy to aide in the passage of ureteral stones. Medical expulsive therapy (MET) has been shown to be cost effective compared with observation followed by treatment. Alpha-adrenergic receptor blockers are most commonly prescribed to promote passage of ureteral stones. They are able to facilitate stone passage, reduce time to passage, and decrease pain. Calcium-channel blockers also increase stone-passage rates. Steroids are useful adjuncts in MET.

Prospective randomized trial comparing efficacy of alfuzosin and tamsulosin in management of lower ureteral stones

OBJECTIVES

To study the efficacy of alfuzosin compared with tamsulosin in the management of lower ureteral stones.

METHODS

A total of 102 patients with stones <1 cm size and located in the lower ureter were enrolled in the present study and randomized into 3 equal groups. Group 1 patients (n = 34) received 0.4 mg tamsulosin daily, group 2 patients (n = 34) received 10 mg alfuzosin daily, and group 3 patients (n = 34) received placebo (control group). The patients were given 75 mg diclofenac injection intramuscularly on demand and were followed up for 4 weeks.

RESULTS

The average stone size for groups 1, 2, and 3 was comparable (6.17, 6.70, and 6.35 mm, respectively). Stone expulsion was observed in 28 of 34 patients (82.3%) in group 1, 24 of 34 patients (70.5%) in group 2, and 12 of 34 patients (35.2%) in group 3. The average expulsion time for groups 1, 2, and 3 was 12.3, 14.5, and 24.5 days, respectively. The results of both study groups (groups 1 and 2) were superior to those in the placebo group (P = .003 and P = .001, respectively), but the study failed to show any statistically significant differences between tamsulosin and alfuzosin (P = .25). Alfuzosin was associated with fewer side effects than tamsulosin, especially in terms of retrograde ejaculation.

CONCLUSIONS

Medical treatment of lower ureteral calculi with tamsulosin and alfuzosin resulted in a significantly increased stone expulsion rate, decreased expulsion time, and a reduced need for analgesic therapy.

Myth: nephrolithiasis and medical expulsive therapy

There is a medical myth that ureteral stones larger than 5 mm will not pass spontaneously and require urological intervention for removal. Recent findings indicate that medical expulsive therapy can facilitate spontaneous passage for stones up to 10 mm. For the management of ureteral stones, we recommend administering tamsulosin and a corticosteroid (deflazacort or prednisone) along with the standard therapy of analgesics, antibiotics and hydration.

Cost-Effectiveness of Medical Expulsive Therapy Using Alpha-Blockers for the Treatment of Distal Ureteral Stones

OBJECTIVE

Medical expulsive therapy (MET) has recently emerged as an efficacious and safe option for the initial management of ureteral stones. The objective of this study was to assess the cost-effectiveness of MET compared with conservative therapy for the treatment of ureteral stones using international cost data from the United States and four European countries.

MATERIAL AND METHODS

A decision analysis model was built with the use of TreeAge Pro 2004 software with linear success rate assumptions. The likelihood of spontaneous passage of ureteral stones according to their size and location was estimated with the use of data derived from a published meta-analysis. The estimated cost of ureteroscopy (URS) in the United States ($4973) was based on the mean cost of 121 consecutive cases performed at a large metropolitan hospital. URS costs for other countries were obtained from a published international survey. The cost of tamsulosin ($2.08 per day), currently the most commonly used medical expulsive agent, was estimated as a mean of the costs obtained from two national pharmacy chains. MET and conservative therapies were compared with the use of one-way and two-way sensitivity analyses.

RESULTS

In the United States, MET using tamsulosin resulted in a $1132 cost advantage over observation. MET maintained its cost advantage even in countries where the cost of URS is much lower than in the United States. Two-way sensitivity analysis showed that MET remained cost-effective even with very low rates of spontaneous passage, minimal benefit of MET, or low cost of URS.

CONCLUSION

MET is a cost-effective strategy for the management of distal ureteral stones--even those with a low rate of spontaneous passage--providing another incentive for initial "facilitated observation" before embarking on surgical intervention.

Pharmacological management of renal colic in the older patient

Renal colic affects up to 12% of the population. Initial management of most patients is expectant. Acute symptom management of renal colic is best accomplished with a combination of parenteral opioids and NSAIDs. The elderly patient with a kidney stone should be screened for contraindications to NSAID therapy, such as renal failure or previous peptic ulcer disease. Use of parenteral opioids is often necessary during the acute setting, and downward-adjusted doses and monitoring are necessary to prevent associated confusion and respiratory depression. Novel therapy with desmopressin may also be effective for symptom control at the initial presentation, without the adverse effects of opioids or NSAIDs. However, use of desmopressin in the elderly must be undertaken cautiously, given the potential adverse effects of this agent. Many small, distal ureteral stones are treated initially with watchful waiting for the first 2-4 weeks after presentation. The patient should have effective, non-parenteral analgesics for use at home. Included in these agents are oral or suppository NSAIDs and oral opioids. Medical expulsion therapy with alpha-adrenoceptor antagonists or calcium channel antagonists is efficacious. alpha-Adrenoceptor antagonists such as the alpha(1A/)(1)(D)-selective tamsulosin are well tolerated in the elderly and increase the rate of spontaneous stone passage by approximately 50% for small distal stones. These agents also appear to decrease the severity of renal colic. Corticosteroids and calcium channel antagonists are also effective but their use in the elderly is not recommended as first-line therapy.

Economics of stone management

Cost, in addition to efficacy and morbidity, has become an important factor in determining the best therapeutic modality for a variety of disease states. A comprehensive literature search finds that, in general, for staghorn calculi, percutaneous nephrostolithotomy is more cost-effective than shock wave lithotripsy (SWL) for stones greater than 2 cm in any dimension, while SWL may be cost-effective for smaller stones. For ureteral stones, observation is the least costly treatment strategy. Among surgical options, ureteroscopy is less costly than SWL. For single and recurrent stone formers, medical prophylactic strategies involving drug therapy are more costly than conservative therapy involving dietary measures alone. However, drug strategies yield fewer stone recurrences.

Pharmacological effect on pyeloureteric dynamics with a clinical perspective: a review of the literature

We searched to review experimental and clinical trials concerning the capabilities of impacting on the ureteric and pelvic activity by means of pharmacological stimulation. Ureteropyeloscopy may cause high renal pelvic pressure. The normal pressure is in the range of 5-15 mmHg whereas pressure of 410 mmHg has been measured during endoscopy. The threshold pressure for intrarenal reflux is about 35 mmHg. Studies in animals have revealed that high renal pelvic pressures may cause permanent damage to the renal parenchyma. Furthermore, it has been demonstrated that elevated pressures may entail an increased risk of several complications related to endourological procedures including bleeding, perforation and infection. In other words, means by which intrarenal pressure could be lowered during endourological procedures might be beneficial with respect to clinical outcomes. In vitro experiments support the existence of different receptors in the ureter and renal pelvis. The ureteric and pelvic responses to the corresponding neurotransmitters have been determined. It seems that alpha-adrenergic and cholinergic agents are stimulating whereas beta-adrenergic agents inhibit ureteric activity. The effect may depend on the mode of administration. Drugs exerting advantageous effects in the pyeloureter may cause undesirable systemic side effects when administered intravenously. In animal studies, renal pelvic pressure can be significantly lowered by topical administration of beta-adrenergic agonists without systemic side effects. In vivo human studies are necessary to clarify the exact dose-response relationship and the degree of urothelial absorption of a drug before clinical use may be adopted.

Nifedipine: Ureteral Stones

Off-Label Drug Uses — This Hospital Pharmacy feature is extracted from Off-Label DrugFacts, a quarterly publication available from Wolters Kluwer Health. Off-Label DrugFacts is a practitioner-oriented resource for information about specific FDA-unapproved drug uses. This new guide to the literature will enable the health care professional/clinician to quickly identify published studies on off-label uses and to determine if a specific use is rational in a patient care scenario. The most relevant data are provided in tabular form, so the reader can easily identify the scope of information available. A summary of the data—including background, study design, patient population, dosage information, therapy duration, results, safety, and therapeutic considerations—precedes each table of published studies. References direct the reader to the full literature for more comprehensive information prior to patient care decisions. Direct questions or comments regarding “Off-Label Drug Uses” to hospitalpharmacy@wolterskluwer.com .

A systematic review of medical therapy to facilitate passage of ureteral calculi

STUDY OBJECTIVE

Acute renal colic is a common presenting complaint to the emergency department. Recently, medical expulsive therapy using alpha-antagonists or calcium channel blockers has been shown to augment stone passage rates of moderately sized, distal, ureteral stones. Herein is a systematic evaluation of the use of medical expulsive therapy to facilitate ureteral stone expulsion.

METHODS

We searched the databases of MEDLINE, EMBASE, and the Cochrane Controlled Trials Register. Additional sources included key urologic journals and bibliographies of selected articles. We included studies that incorporated a randomized or controlled clinical trial design, patients older than 18 years, treatment in which an alpha-antagonist or calcium channel blocker was compared to a standard therapy group, and studies that reported stone expulsion rates. A random effects model was used to obtain summary risk ratios (RRs) and 95% confidence intervals (CIs) for stone expulsion rate.

RESULTS

A pooled analysis of 16 studies using an alpha-antagonist and 9 studies using a calcium channel blocker suggested that the addition of these agents compared to standard therapy significantly improved spontaneous stone expulsion (alpha-antagonist RR 1.59; 95% CI 1.44 to 1.75; number needed to treat 3.3 [95% CI 2.1 to 4.5]; calcium channel blocker RR 1.50; 95% CI 1.34 to 1.68; number needed to treat 3.9 [95% CI 3.2 to 4.6]) in patients with distal ureteral stones. Subgroup analysis of trials using concomitant medications (ie, low-dose steroids, antibiotics, and elimination of trials using an anticholinergic agent) yielded a similar improvement in stone expulsion rate. Adverse effects were noted in 4% of patients receiving alpha-antagonist and in 15.2% of patients receiving calcium channel blockers.

CONCLUSION

Our results suggest that "medical expulsive therapy," using either alpha-antagonists or calcium channel blockers, augments the stone expulsion rate compared to standard therapy for moderately sized distal ureteral stones.

Treatment Selection and Outcomes: Ureteral Calculi

The most important recent advances in the management of ureteral calculi have been the development of medical expulsive therapy to facilitate passage of ureteral stones, such that many calculi that would previously have required procedural treatment now exit the ureter with only pharmacologic treatment; and the improvements in ureteroscopic technology that have enabled retrograde ureteroscopy to become a first-line option for most ureteral stones. Shock wave lithotripsy still plays an important role for many ureteral calculi, particularly smaller ones, and the addition of percutaneous/antegrade ureteroscopy and laparoscopic ureterolithotomy rounds out the treatment options for large or impacted stones. Selection of treatment based upon factors such as size, location, and others will optimize outcome for patients who have ureteral calculi.

Examination of alpha 1 adrenoceptor subtypes in the human ureter

AIM

Urinary stone disease is a common condition affecting up to 12% of the population. Speedy elimination of ureterolithiasis in the lower part of ureters is reported with the alpha 1-blocker. This study was carried out to characterize the alpha 1 adrenoceptors (AR) subtype gene and protein expression in the proximal, medial, and distal regions of the human ureter with the aim of facilitating stone expulsion.

METHODS

The study was carried out on 20 volunteers. Proximal, medial and distal ureter specimens were obtained as discarded tissues after nephroureterectomy for renal pelvic or ureteral carcinoma. Proximal ureter specimens were obtained as discarded tissues after nephrectomy for renal carcinoma. Using ureter samples, real-time reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemical staining were performed.

RESULTS

The alpha 1d subtype mRNA was highly expressed in each ureteral region, accounting for about 54% of the total AR Messenger Ribonucleic Acid. In the proximal and medial ureter, the distribution of ARs was alpha 1d > or = alpha 1a > alpha 1b as well as that of the total ureter. The distal ureter expressed the highest amount of alpha 1d ARs. The alpha 1d subtype expression tended to be high compared with the alpha 1a subtype expression. In the distal ureter, the distribution of ARs was alpha 1d > alpha 1a > alpha 1b. Immunohistochemical staining revealed that expressions of alpha 1a-AR and alpha 1d-AR were higher than that of alpha 1b-AR.

CONCLUSIONS

According to our results, we should try the alpha 1d AR antagonist for the conservative expulsive therapy of distal ureteral stones in the highest region of alpha 1d subtype distribution.

Is There a Role for Tamsulosin in Shock Wave Lithotripsy for Renal and Ureteral Calculi?

PURPOSE

We evaluated the effect of the alpha-blocker tamsulosin on stone clearance, analgesic requirements and steinstrasse in shock wave lithotripsy for solitary renal and ureteral calculus.

MATERIALS AND METHODS

A prospective, double-blind, randomized placebo controlled study was performed during 1 year involving 60 patients with a solitary renal or ureteral calculus undergoing shock wave lithotripsy. The control group (30) received 0.4 mg tamsulosin and the study group (30) received placebo daily until stone clearance or for a maximum of 30 days. An oral preparation of dextropropoxyphene hydrochloride and acetaminophen was the analgesic used on an on-demand basis. The parameters assessed were stone size, position, clearance time, effect on steinstrasse and analgesic requirement.

RESULTS

The overall clearance rate was 96.6% (28 of 29) in the study group and 79.3% (23 of 29) in the control group (p = 0.04). With larger stones 11 to 24 mm the difference in the clearance rate was significant (p = 0.03) but not so with the smaller stones 6 to 10 mm (p = 0.35). The average dose of analgesic used was lower with tamsulosin than with controls, without statistical significance. Steinstrasse resolved spontaneously in the tamsulosin group whereas 25% (2 of 8) required intervention in the placebo group. There was no difference between the 2 groups with regard to age, stone size or location.

CONCLUSIONS

The alpha-blocker tamsulosin seemed to facilitate stone clearance, particularly with larger stones during shock wave lithotripsy for renal and ureteral calculus. It also appeared to improve the outcome of steinstrasse. Tamsulosin may have a potential role in routine shock wave lithotripsy.

Comparative Evaluation of Efficacy of Use of Tamsulosin and/or Tolterodine for Medical Treatment of Distal Ureteral Stones

OBJECTIVES

To evaluate the activity of the therapeutic agents (tamsulosin and/or tolterodine) used to accelerate the expulsion of stones and to reduce the probable complications during observation of the medical treatment of distal ureteral stones to allow spontaneous passage.

METHODS

A total of 120 patients with distal ureteral stones were included in the study. Patients with stones less than 10 mm and allowing urinary flow were included in the study. The patients were studied in four randomly divided groups. Group 1 patients received tamsulosin 0.4 mg/day, group 2 patients received tamsulosin 0.4 mg/day plus tolterodine 2 mg (twice a day), group 3 patients received tolterodine 2 mg (twice a day), and group 4 patients did not receive any medical treatment (control group).

RESULTS

Differences among the four groups in patient age and stone dimension were not statistically significant (P >0.05). The stone expulsion rates were greater (P <0.05) in groups 1 and 2 than in groups 3 and 4. A significant variation (P <0.05) regarding the time to stone expulsion was observed in groups 1 and 2.

CONCLUSIONS

In our study, the use of tamsulosin for the expulsion of distal ureteral stones was effective; however, the use of tolterodine provided no additional advantages.

Efficacy of expulsive therapy using nifedipine or tamsulosin, both associated with ketoprofene, after shock wave lithotripsy of ureteral stones

Extracorporeal shock wave lithotripsy (ESWL) is currently considered one of the main treatments for ureteral stones. Some studies have reported the effectiveness of pharmacologic therapies (calcium antagonists or alpha-blockers) in facilitating ureteral stone expulsion after ESWL. We prospectively evaluated the efficacy, after ESWL, of nifedipine on upper-middle ureteral stones, and tamsulosin on lower ureteral stones, both associated to ketoprofene as anti-edema agent. From January 2003 to March 2005 we prospectively evaluated 113 patients affected by radiopaque or radiolucent ureteral stones. Average stone size was 10.16 +/- 2.00 mm (range 6-14 mm). Thirty-seven stones were located in the upper ureter, 27 in the middle ureter, and 49 in the lower ureter. All patients received a single session of ESWL (mean number of shock waves: 3,500) by means of a Dornier Lithotripter S (mean energy power for each treatment: 84%). Both ultrasound and X-ray were used for stone scanning. After treatment, 63 of 113 patients were submitted to medical therapy to aid stone expulsion: nifedipine 30 mg/day for 14 days administered to 35 patients with upper-middle ureteral stones (group A1) and tamsulosin 0.4 mg/day for 14 days administered to 28 patients with stones located in the distal ureter (group A2). The remaining 50 patients were used as a control group (29 upper-middle ureteral stones-B1-and 21 lower ureteral stones-B2-), receiving only pain-relieving therapy. No significant difference in stone size between the groups defined was observed. Stone clearance was assessed 1 and 2 months after ESWL by means of KUB, ultrasound scan and/or excretory urography. A stone-free condition was defined as complete stone clearance or the presence of residual fragments smaller than 3 mm in diameter. The stone-free rates in the expulsive medical therapy group were 85.7 and 82.1% for the nifedipine (A1) and tamsulosin (A2) groups respectively; stone-free rates in the control groups were 51.7 and 57.1% (B1 and B2, respectively). Five patients (14.3%) in group A1, 5 (17.8%) in group A2, 14 (48.3%) in group B1 and 9 (42.8%) in group B2 were not stone-free after a single ESWL session and required ESWL re-treatment or an endoscopic treatment. Medical therapy following ESWL to facilitate ureteral stone expulsion results in increased 1- and 2-month stone-free rates and in a lower percentage of those needing re-treatment. The efficacy of nifedipine for the upper-mid ureteral tract associated with ketoprofene makes expulsive medical therapy suitable for improving overall outcomes of ESWL treatment for ureteral stones.

Medical Therapy of Urolithiasis

Nephrolithiasis treatment has become easier and less invasive with the development of extracorporeal shockwave lithotripsy (SWL) and endourologic techniques. However, medical therapy represents a well-established and complementary approach that can improve the efficacy of SWL and endourology. During recent decades, pharmacologic intervention has become more effective in stone disease: drugs can control the pain of renal colic, interfere at various levels in lithogenesis, and contribute to the expulsion of stones. It is well known that lithogenesis is a multifactorial process influenced by environmental-nutritional factors (low urinary volume, diet rich in animal protein, etc) and metabolic alterations; i.e., hypercalciuria, hyperuricosuria, and deficiency of stone-inhibiting factors (citrate, magnesium, glycosaminoglycans [GAGs]). Specific drugs such as citrate, allopurinol, and thiazide represent highly effective treatments for the promoting factors. Furthermore, recent findings suggest an interesting role for a phytotherapeutic agent, Phillantus niruri, and its inhibitory action on calcium oxalate crystallization related to the higher incorporation of GAGs into the calculi. Another step forward in medical management of stone disease is expulsive therapy. Many studies have proven the efficacy of medical expulsive therapy with nifedipine and alpha-blockers: their specific action on ureteral smooth muscle in association with anti-edema drugs accounts for their efficacy in expelling ureteral stones. In this paper, we provide an update on the medical treatment of stone disease, focusing our attention on what is known and what is new in renal colic and litholithic and expulsive medical therapy.

First Prize: Pharmacologic Manipulation of the Porcine Ureter: Acute Impact of Topical Drugs on Ureteral Diameter and Peristaltic Activity

BACKGROUND AND PURPOSE

Intraluminal application of pharmacologic agents for acute ureteral dilation may facilitate difficult ureteroscopy. We characterized the in-vivo effects of intraluminal application of verapamil and theophylline on ureteral peristalsis and diameter in a porcine model.

MATERIALS AND METHODS

Twenty-four female domestic pigs (35-40 kg) were incorporated into the study. We deployed a giant magneto resistive (GMR) sensor and electromagnetic (EMG) electrodes laparoscopically onto the ureteral surface for simultaneous measurement of the mechanical and electrical signals of ureteral peristalsis, respectively. The ureteral-luminal diameter was measured at three levels by digital retrograde pyelography and standardized to a 10-mm laparoscope. The results were calculated as change in peristalsis and ureteral diameter from baseline during the first hour after drug injection. We tested two smooth-muscle relaxants, verapamil (2 mg/kg) and theophylline (70 mg/kg), with saline and dimethylsulfoxide (DMSO; solvent) as controls. Six pigs were studied for each of the four groups. Hydration, anesthesia, and intra-abdominal pressure were standardized. The serum concentrations of the drugs were measured to determine systemic absorption.

RESULTS

During the first 10 minutes after intraluminal drug injection, theophylline caused a significant decrease in ureteral peristalsis (6.75 waves/10 minutes) compared with the control group (1.00/10 minutes; P = 0.02). This trend persisted for the next hour. However, there were no changes from baseline in ureteral width. Ureteral peristalsis and dilation remained similar after the saline and DMSO injections. Verapamil increased the diameter of the proximal ureter compared with the controls throughout the hour after drug injection. Fifteen minutes after the drug injection, the change in the ureteral diameter with verapamil was 1.38 mm (4.14F), while the control group showed a change of 0.27 mm (P = 0.03). At 1 hour, the width of the proximal ureter in the verapamil group had increased by 1.72 mm (5.16F), while the control group had changed by 0.55 mm (P = 0.03). There were no statistically significant changes in the widths of the mid or distal ureter. No ureteral dilation was observed in the other groups.

CONCLUSIONS

In the porcine model, intraluminal application of pharmacologic agents produced independent effects on ureteral dilation and peristalsis. Theophylline inhibited ureteral peristalsis, and verapamil produced acute proximal-ureteral dilation. The ability to alter ureteral diameter or peristaltic activity acutely may facilitate ureteroscopy.

Medical therapy to facilitate urinary stone passage: a meta-analysis

BACKGROUND

Medical therapies to ease urinary-stone passage have been reported, but are not generally used. If effective, such therapies would increase the options for treatment of urinary stones. To assess efficacy, we sought to identify and summarise all randomised controlled trials in which calcium-channel blockers or alpha blockers were used to treat urinary stone disease.

METHODS

We searched MEDLINE, Pre-MEDLINE, CINAHL, and EMBASE, as well as scientific meeting abstracts, up to July, 2005. All randomised controlled trials in which calcium-channel blockers or alpha blockers were used to treat ureteral stones were eligible for inclusion in our analysis. Data from nine trials (number of patients=693) were pooled. The main outcome was the proportion of patients who passed stones. We calculated the summary estimate of effect associated with medical therapy use using random-effects and fixed-effects models.

FINDINGS

Patients given calcium-channel blockers or alpha blockers had a 65% (absolute risk reduction=0.31 95% CI 0.25-0.38) greater likelihood of stone passage than those not given such treatment (pooled risk ratio 1.65; 95% CI 1.45-1.88). The pooled risk ratio for alpha blockers was 1.54 (1.29-1.85) and for calcium-channel blockers with steroids was 1.90 (1.51-2.40). The proportion of heterogeneity not explained by chance alone was 28%. The number needed to treat was 4.

INTERPRETATION

Although a high-quality randomised trial is necessary to confirm its efficacy, our findings suggest that medical therapy is an option for facilitation of urinary-stone passage for patients amenable to conservative management, potentially obviating the need for surgery.

A comparative in vitro study to determine the beneficial effect of calcium-channel and alpha(1)-adrenoceptor antagonism on human ureteric activity

OBJECTIVE

To compare the in vitro human ureteric muscle response to calcium-channel and alpha-adrenoceptor antagonists, to determine the promoting factor for stone passage. Clinical trials suggest that stone passage in renal colic can be promoted by ureteric relaxation using these agents, however nonsteroidal anti-inflammatory drugs appear to reduce ureteric activity in vitro but do not promote stone passage when used in clinical trials.

MATERIALS AND METHODS

Human ureteric muscle strips were used to record the effect that each drug had on muscle tone in vitro. The ureter was obtained at open nephrectomy or cystectomy. Potassium-enriched Krebs' solution was used to evoke maximal muscle tone, followed by adding each drug in increasing concentrations to determine the percentage reduction in tone. The drugs used to represent each group were nifedipine, 5-methylurapidil (5-MU) and diclofenac. In all, 201 ureteric strips were obtained from 39 patients.

RESULTS

At all drug concentrations, the in vitro relaxant effect of nifedipine and 5-MU was greater than that of diclofenac. At 10(-5) M the median reduction in proximal and distal ureteric tone to diclofenac, nifedipine and 5-MU were 18%, 5% and 47%, vs 57%, 33% and 65%, respectively.

CONCLUSION

Nifedipine and 5-MU produced greater ureteric relaxation in vitro than diclofenac; they predominantly relax distal ureter. This suggests that a reduction in ureteric muscle tone, as opposed to complete ablation of activity, might be the promoting factor for stone passage.

Corticosteroids and Tamsulosin in the Medical Expulsive Therapy for Symptomatic Distal Ureter Stones: Single Drug or Association?

OBJECTIVES

To assess the clinical role of corticosteroids in the medical expulsive therapy of symptomatic distal ureteral stones.

METHODS

Between January 2004 and September 2005, 114 patients with symptomatic distal ureteral stones with a >/=5mm diameter were enrolled in this prospective study and divided into four groups based on the urologist (of four) who treated them in the emergency unit. Group A (33 patients) received tamsulosin (0.4mg daily), group B (24 patients) received deflazacort (30mg daily), group C (33 patients) received both (0.4mg tamsulosin+30mg deflazacort daily), and control group D (24 patients) received only analgesics. The treatment duration was 10 d to prevent the side-effects of prolonged corticosteroid therapy. The end points were the expulsion rate, analgesic consumption, number of ureteroscopies, and safety.

RESULTS

The groups were comparable in terms of age, sex, and stone location. The stone diameter was 5.96+/-0.33mm for group A, 5.83+/-0.4mm for group B, 5.88+/-0.23mm for group C, and 5.71+/-0.5mm (p>0.05) for group D. The rates of expulsion for the four groups were 60%, 37.5%, 84.8%, and 33.3%, respectively. There was a significant difference between group C and the other groups (p<0.001). The mean analgesic consumption was 42.5+/-0.4mg for group A, 50+/-0.3mg for group B, 27.3+/-0.5mg for group C, and 81+/-0.33mg for group D, with a significant difference between group C and the other groups (p<0.001). During the treatment period, only two cases of drug side-effects related to tamsulosin (without any drop-outs) were recorded.

CONCLUSION

When the medical expulsive therapy for symptomatic distal ureteral stones is considered, the use of steroids (deflazacort) proves efficient only when administered together with alpha(1)-blockers (tamsulosin). In addition, tamsulosin used on its own as a medical expulsive therapy can be considered as an alternative treatment for those patients who are not suitable for steroid therapy, as it is generally efficient.

Physiologic Effect of Nifedipine and Tamsulosin on Contractility of Distal Ureter

BACKGROUND AND PURPOSE

Renal colic not only leads to significant morbidity but imposes a financial burden on society in lost productivity and healthcare dollars spent. Both tamsulosin and nifedipine can facilitate spontaneous stone passage in the distal ureter and reduce the associated colic. We evaluated the physiologic effect of these agents on the distal pig ureter.

MATERIALS AND METHODS

Bilateral ureters were removed en bloc with the bladder trigone from three pigs. Five-millimeter rings were taken from the intramural and distal ureter. Isometric tension recording was performed during both spontaneous and electrically stimulated contraction. Measurements of contractile interval and amplitude were taken in baseline buffer solution, nifedipine at 10(-6) g/L, and tamsulosin at 10(-6) g/L. Spontaneous contractile activity was also measured with phenylephrine at 10(-4) g/L followed by tamsulosin at 10(-6) g/L.

RESULTS

Under conditions of spontaneous contractility, phenylephrine decreased the contraction interval by 46%, an effect which was reversed by tamsulosin. Tamsulosin increased the baseline interval by 27% (P < 0.025) and decreased the amplitude by 7% (P > 0.1). Nifedipine blocked all contractile activity. Under stimulated contractility, tamsulosin had no effect on the interval and decreased the amplitude by 7% (P > 0.1). Nifedipine blocked all contractile activity.

CONCLUSIONS

We believe that both tamsulosin and nifedipine prevent the disorganized antiperistalsis associated with ureteral spasm while allowing some degree of antegrade fluid-bolus (stone) propagation. It is this mechanism of action that facilitates spontaneous passage and reduces associated renal colic when tamsulosin and nifedipine are used for the management of ureteral stone disease.

Incontinence after radical prostatectomy: surgical treatment options

PURPOSE OF REVIEW

Stress urinary incontinence is an uncommon finding in healthy men. Following radical prostatectomy, however, stress urinary incontinence is the most important complication influencing patient morbidity following surgery and influencing satisfaction, regardless of the surgical technique applied. Conservative treatment options centre at early restoration of bladder and pelvic floor function. When significant and bothersome stress urinary incontinence persists, even after six to 12 months active treatment follow-up, surgical restoration of continence seems advisable.

RECENT FINDINGS

Two themes emerge in reviewing the recent publications in this field. Implantation of the hydraulic artificial urinary sphincter is still the gold standard, particularly in severe cases. Alternatively, new techniques and other artificial materials are gaining favour, aiming at a large cohort of patients with less severe incontinence, which have been not treated or overtreated so far. Advances in both areas are covered within this review article in detail.

SUMMARY

For treatment of incontinence following prostatectomy, a large variety of surgical techniques are readily available and have proven to be helpful tools in making patients' uncomfortable lives much easier. In addition, the wide armamentarium of artificial materials and techniques may help to choose the proper surgical technique for every patients' needs.

Medical Expulsive Treatment of Distal-Ureteral Stones Using Tamsulosin: A Single-Center Experience

PURPOSE

To evaluate the efficacy of the addition of tamsulosin to our standard expulsive pharmacologic therapy for the treatment of distal-ureteral stones.

PATIENTS AND METHODS

A series of 96 patients referred to our department for the management of symptomatic distal-ureteral calculi were randomly divided into group 1 (N = 46) who received diclofenac (100 mg/daily) plus aescin (80 mg/daily) and group 2 (N = 50) who received the same therapy plus tamsulosin (0.4 mg/daily) for a maximum of 2 weeks. There were no differences between the groups with respect to age, sex, or stone size. The primary endpoint was the expulsion rate. Expulsion time, need for analgesics, need for hospitalization, and drug side effects were the secondary endpoints.

RESULTS

The expulsion rate was significantly higher in group 2 (90%) than in group 1 (58.7%; P = 0.01), and group 2 achieved stone passage in a shorter time (mean 4.4 v 7.5 days, respectively; P = 0.005). Lower analgesic use was found in group 2 (P = 0.003), as well as significantly fewer hospitalizations for recurrent colic (P = 0.01). Both groups experienced few side effects associated with expulsive therapy.

CONCLUSIONS

A conservative approach should be considered as an option in the management of uncomplicated distal-ureteral stones. Even if the best pharmacologic expulsive regimen remains to be established, the use of the selective alpha-blocker tamsulosin is recommended in this setting.

The use of tamsulosin in the medical treatment of ureteral calculi: where do we stand?

It has recently been demonstrated that specific adrenoceptors subtypes (alpha(1A)/alpha(1D)) are prevalent in the distal part of the ureter, a finding supporting the interesting results obtained by different groups with the use of tamsulosin in the treatment of distal ureteral calculi. We performed a prospective randomized study to evaluate the effects of the addition of tamsulosin on our standard pharmacological therapy for the treatment of selected ureteral stones. A total of 64 patients referred to our department for the management of symptomatic ureteral calculi were considered. Patients were randomly divided into two treatment groups: group A (n=32) who received diclofenac (100 mg/daily) plus aescin (80 mg/daily) and group B (n=32) who received the same therapy plus tamsulosin (0.4 mg/daily) for a maximum of 2 weeks. No significant differences were found between the groups for age, gender distribution and mean stone size measured in the single largest dimension at presentation. The stone expulsion rate was 60% (19/32 patients) for group A and 88% for (28/32) for group B with a mean expulsion time of 7.4+/-2.2 (range 3.5-12) and 4.8+/-2.7 days (range 1.8-10.5), respectively. Group B showed a significant advantage in terms of both expulsion rate (P=0.01) and expulsion time (P=0.005). Different analgesics from those used in the standard treatment regimen were required in ten patients in group A (31%) but only three patients in group B (9%). This difference was significant (P=0.003). Hospitalization for recurrent colic was needed in 21% of patients in group A (7/32) and in 9% in group B (3/32) (P=0.01). Only two patients in each group (6%) experienced minor side effects associated with the expulsive therapy. Our data confirm the efficacy of tamsulosin in the treatment of distal ureteral stones up to 1 cm. This selective alpha-blocker should therefore be included in the pharmacological regimen of patients when a conservative approach is considered in the treatment of ureteral lithiasis.

Medical-expulsive therapy for distal ureterolithiasis: randomized prospective study on role of corticosteroids used in combination with tamsulosin-simplified treatment regimen and health-related quality of life

OBJECTIVES

To assess the clinical efficacy of the addition of a corticosteroid drug to tamsulosin in the medical-expulsive therapy of distal ureterolithiasis.

METHODS

Sixty consecutive patients with a symptomatic distal ureteral stone were included in our study and randomized to one of two home treatment groups. Group 1 patients (n = 30) received tamsulosin (0.4 mg daily), and group 2 patients (n = 30) were treated with a corticosteroid drug (deflazacort, 30 mg daily) plus tamsulosin. The treatment duration was until stone expulsion or 28 days, whichever came first. The primary endpoint of the study was the stone expulsion rate. The secondary endpoints were the expulsion time; use of analgesics; number of emergency room admissions, hospitalizations, and workdays lost; drug side effects; and quality of life of the patients (EuroQol questionnaire, EQ-5D) during treatment.

RESULTS

The two groups had a similar expulsion rate (90% for group 1 and 96.7% for group 2; P = 0.612), but the expulsion time was significantly reduced in group 2 patients (P = 0.036). During the treatment period, we did not observe significant differences between the two groups in the number of emergency room visits or hospitalizations, analgesic use, number of workdays lost, or incidence of drug side effects. The quality of life of the patients during therapy, as determined using the EQ-5D, was similar in both groups.

CONCLUSIONS

The use of a corticosteroid drug in association with tamsulosin seemed to induce more rapid stone expulsion. In addition, tamsulosin alone as medical-expulsive therapy for distal ureteral calculi had excellent expulsive effectiveness.

Nonsurgical Management of Urolithiasis: An Overview of Expulsive Therapy

Although minimally invasive stone therapies such as shockwave lithotripsy, ureteroscopy, and percutaneous nephrolithotomy are efficacious, these techniques are not free of risks and are relatively expensive. Watchful waiting may be appropriate in patients without infection whose pain can be controlled with oral medication but is associated with pain, uncertainty, potential risks to renal function, and time lost from work. Hydroxyprogesterone, prostaglandin synthetase inhibitors, calcium-channel blockers such as nifedipine, alpha-1 blockers such as tamsulosin, and corticosteroids may have some beneficial effect. Future studies are likely to provide additional data in support of their use.

RANDOMIZED TRIAL OF THE EFFICACY OF TAMSULOSIN, NIFEDIPINE AND PHLOROGLUCINOL IN MEDICAL EXPULSIVE THERAPY FOR DISTAL URETERAL CALCULI

PURPOSE

Recent studies show the interesting efficacy of different drug combinations for the spontaneous expulsion of distal ureteral stones. We performed a randomized, prospective study to assess and compare the efficacy of 3 drugs as medical expulsive therapy for distal ureteral calculi.

MATERIALS AND METHODS

A total of 210 symptomatic patients with distal ureteral calculi greater than 4 mm were randomly allocated to home treatment with phloroglucinol, tamsulosin or nifedipine (groups 1 to 3, respectively). Each group was given a corticosteroid drug and antibiotic prophylaxis with an injectable nonsteroidal anti-inflammatory drug was also used on demand. The primary end point was the expulsion rate and the secondary end points were expulsion time, analgesic use, need for hospitalization and endoscopic treatment as well as the number of workdays lost, quality of life and drug side effects

RESULTS

The expulsion rate was significantly higher in group 2 (97.1%) than in groups 1 (64.3%, p <0.0001) or 3 (77.1%, p <0.0001). Group 2 significantly achieved stone passage in a shorter time than the other 2 groups and showed a significantly decreased number of hospitalizations as well as a better decrease in endoscopic procedures performed to remove the stone. The control of renal colic pain was significantly superior in group 2 compared with the other groups, resulting in fewer workdays lost. Group 3 showed lower analgesic use and decreased workdays lost compared with group 1. No difference in side effects was observed among the groups.

CONCLUSIONS

Medical expulsive therapy should be considered for distal ureterolithiasis without complications before ureteroscopy or extracorporeal lithotripsy. The use of tamsulosin in this treatment regimen produced stone expulsion in almost all cases in a short time, allowing complete home patient treatment.

Tamsulosin treatment increases clinical success rate of single extracorporeal shock wave lithotripsy of renal stones

OBJECTIVES

To design a randomized, no-treatment, controlled, prospective study to determine whether the administration of tamsulosin, as adjunctive medical therapy, increases the efficacy of one extracorporeal shock wave lithotripsy (ESWL) session to treat renal stones and decreases the use of analgesic drugs after the procedure.

METHODS

A total of 130 patients underwent a single ESWL session to treat solitary radiopaque renal stones 4 to 20 mm in diameter. After treatment, all patients were randomly assigned to receive our standard medical therapy alone (controls) or in association with 0.4 mg tamsulosin daily for a maximum of 12 weeks. All 130 patients were followed up for 3 months or until an alternative treatment was given.

RESULTS

Of the 130 patients, 78.5% of those receiving tamsulosin and 60% of controls had achieved clinical success at 3 months (P = 0.037). When we stratified patients according to stone size, for those with a stone size larger than 10 mm, the success rate was significantly greater in the tamsulosin group (P = 0.028). Renoureteral colic occurred in 76.9% of patients treated with standard therapy but in only 26.1% of those receiving tamsulosin (P < 0.001). The mean cumulative diclofenac dose was 375 mg per patient in the tamsulosin group and 675 mg per patient in the control group (P < 0.001).

CONCLUSIONS

The results of our study have demonstrated that tamsulosin therapy, as an adjunctive medical therapy after ESWL, is more effective than lithotripsy alone for the treatment of patients with large renal stones and is equally safe. In addition, our results also indicated that adjunctive treatment with tamsulosin could decrease the use of analgesic drugs after ESWL.

Urologic diseases in America project: urolithiasis

PURPOSE

We quantified the burden of urolithiasis in the United States by identifying trends in the use of health care resources and estimating the economic impact of the disease.

MATERIALS AND METHODS

The analytical methods used to generate these results have been described previously.

RESULTS

The rate of national inpatient hospitalizations for a diagnosis of urolithiasis decreased by 15% and hospital length of stay decreased from 2.6 to 2.2 days between 1994 and 2000. Rates of hospitalization were 2.5 to 3-fold higher for Medicare beneficiaries with little change between 1992 and 1998. Almost 2 million outpatient visits for a primary diagnosis of urolithiasis were recorded in 2000. Hospital outpatient visits increased by 40% between 1994 and 2000 and physician office visits increased by 43% between 1992 and 2000. In the Medicare population hospital outpatient and office visits increased by 29% and 41%, respectively, between 1992 and 1998. The distribution of surgical procedures remained relatively stable through the 1990s. Shock wave lithotripsy was the most commonly performed procedure, followed closely by ureteroscopy. Overall the total estimated annual expenditure for individuals with claims for a diagnosis of urolithiasis was almost $2.1 billion in 2000, representing a 50% increase since 1994.

CONCLUSIONS

The cost of urolithiasis is estimated at almost $2 billion annually and it appears to be increasing with time despite a shift in inpatient to outpatient treatment and the emergence of minimally invasive treatment modalities, perhaps because the prevalence of stone disease is increasing.

Nifedipine versus tamsulosin for the management of lower ureteral stones

PURPOSE

We evaluate and compare the effectiveness of 2 different medical therapies during watchful waiting in patients with lower ureteral stones.

MATERIALS AND METHODS

A total of 86 patients with stones less than 1 cm located in the lower ureter (juxtavesical or intramural tract) were enrolled in the study and were randomly divided into 3 groups. Group 1 (30) and 2 (28) patients received daily oral treatment of 30 mg deflazacort, (maximum 10 days). In addition group 1 patients received 30 mg nifedipine slow-release (maximum 28 days) and group 2 received 1 daily oral therapy of 0.4 mg tamsulosin (maximum 28 days), Group 3 patients (28) were used as controls. Statistical analyses were performed using Student's test, ANOVA test, chi-square test and Fisher's exact test.

RESULTS

The average stone size for groups 1 to 3 was 4.7, 5.42 and 5.35 mm, respectively, which was not statistically significant. Expulsion was observed in 24 of 30 patients in group 1 (80%), 24 of 28 in group 2 (85%) and 12 of 28 in group 3 (43%). The difference in groups 1 and 2 with respect to group 3 was significant. Average expulsion time for groups 1 to 3 was 9.3, 7.7 and 12 days, respectively. A statistically significant difference was noted between groups 2 and 3. Mean sodium diclofenac dosage per patient in groups 1 to 3 was 19.5, 26, and 105 mg, respectively. A statistical significant difference was observed between groups 1 and 2 with respect to group 3.

CONCLUSIONS

Medical treatments with nifedipine and tamsulosin proved to be safe and effective as demonstrated by the increased stone expulsion rate and reduced need for analgesic therapy. Moreover medical therapy, particularly in regard to tamsulosin, reduced expulsion time.

Efficacy of Tamsulosin in the Medical Management of Juxtavesical Ureteral Stones

PURPOSE

We evaluated the efficacy of the alpha1-adrenergic antagonist tamsulosin for conservative expulsive therapy in patients with ureteral colic due to juxtavesical stones.

MATERIALS AND METHODS

A total of 60 consecutive symptomatic patients with stones located in the juxtavesical tract of the ureter were randomly divided into group 1--30 who received oral floroglucine-trimetossibenzene 3 times daily and group 2--30 who received 0.4 mg tamsulosin daily. The 2 groups received 30 mg deflazacort daily for 10 days plus cotrimoxazole 2 times daily for 8 days and 75 mg diclofenac injected intramuscularly on demand. Ultrasound followup and medical visits were performed weekly for 4 weeks. Stone passage rate and time, analgesic use, hospitalization and endoscopical intervention were evaluated. Statistical analysis was performed using the Student t test.

RESULTS

The stone expulsion rate was 70% for group 1 and 100% for group 2. Mean stone size was 5.8 and 6.7 mm, respectively (p = 0.001). Mean expulsion time was 111.1 hours for group 1 and 65.7 hours for group 2 (p = 0.020). The mean number of diclofenac injections was 2.83 for group 1 and 0.13 for group 2 (p <0.0001). Ten group 1 patients were hospitalized, of whom 9 underwent ureteroscopy, compared with none in group 2 (p <0.0001 and 0.001, respectively).

CONCLUSIONS

Tamsulosin used as a spasmolytic drug during renal colic due to juxtavesical calculi increased the stone expulsion rate and decreased expulsion time, the need for hospitalization and endoscopic procedures, and provided particularly good control of colic pain.

Pharmacological profile of KUL-7211, a selective beta-adrenoceptor agonist, in isolated ureteral smooth muscle

Since, in the human ureter, both beta(2)- and beta(3)-adrenoceptors mediate adrenergic-stimulation-induced relaxation, selective beta(2)-/beta(3)-adrenoceptor agonists might prove clinically useful for relieving ureteral colic and promoting stone passage. We evaluated the beta-adrenoceptor subtype selectivity and ureteral-relaxing efficacy of (-)-2-[4-(2-[[(1S,2R)-2-hydroxy-2-(4-hydroxyphenyl)-1-methylethyl]amin] ethyl)phenyloxy]acetic acid (KUL-7211), a new beta-adrenoceptor agonist, in vitro. In rat isolated organs, its selectivities, for inhibition of spontaneous uterine contraction (mediated via beta(2)-adrenergic stimulation) and inhibition of colonic contraction (via beta(3)-adrenergic stimulation) versus increase in atrial rate (via beta(1)-adrenergic stimulation), were 56.3 and 242.2, respectively. KUL-7211 relaxed 80-mM-KCl-induced tonic contractions in both rabbit (pD(2) value: 5.86 +/- 0.13, whose ureteral relaxation is mediated via beta(2)-adrenergic stimulation) and canine (pD(2) value: 6.52 +/- 0.16, via beta(3)-adrenergic stimulation) isolated ureters in a concentration-dependent manner. These KUL-7211-induced relaxing effects were antagonized by ICI-118,551 (selective beta(2)-adrenoceptor antagonist, pK(B) value: 8.91 +/- 0.24) in the rabbit ureter and by bupranolol (non-selective beta-adernoceptor antagonist, pK(B) value: 6.85 +/- 0.12) in the canine ureter. KUL-7211 also reduced the spontaneous rhythmic contraction in a canine ureteral spiral preparation in a concentration-dependent manner, the pD(2) value being 6.83 +/- 0.20. These data clearly demonstrate that KUL-7211 selectively stimulates both ureteral beta(2)- and beta(3)-adrenoceptors and potently relaxes ureteral smooth muscle. KUL-7211 may be a novel and useful medication for relieving ureteral colic and promoting stone passage in urolithiasis patients.

Modification of ureteral motility and promotion of urine flow around an intraureteral obstruction by CL-316243, phenylephrine, and furosemide in dogs

The aim of this study was to evaluate the effects of a beta3-adrenoceptor (AR) agonist (CL-316243), an alpha1-AR agonist (phenylephrine), and a loop diuretic (furosemide) on the spontaneous rhythmic contractions of the isolated canine ureter and on an acute ureteral obstruction produced by inflation of a balloon catheter in anesthetized dogs. In the isolated ureter, CL-316243 concentration dependently reduced both the amplitude and frequency of the rhythmic contractions (pD(2): 7.19 +/- 0.33), whereas phenylephrine significantly enhanced both variables (pD(2): 5.26 +/- 0.09) and furosemide reduced them only slightly. In the acute ureteral obstruction model, the intraureteral pressure (IUP) gradually rose to reach a plateau of 58.9 mm Hg after inflation of a balloon catheter within the lower ureter. Intravenous administration of CL-316243 (0.3 microg/kg) significantly reduced the elevated IUP and the resumed urine flow (UF), leading to a sustained reduction in the IUP. In contrast, the IUP continued to increase above the plateau level for 10 minutes after phenylephrine administration (10 microg/kg) and for 30 minutes after furosemide administration (1,000 microg/kg). In the phenylephrine group, the UF resumed when the IUP reached 75.8 mm Hg, and thereafter the IUP gradually decreased in parallel with the increase in the UF. From these results, we conclude that in dogs, CL-316243 reduces the IUP by allowing the UF to resume as a result of a relaxation of ureter at the obstruction site, whereas with phenylephrine, the reduction in the IUP is secondary to a resumption in the UF resulting from an induced contraction of ureter that causes an increase in hydrostatic pressure above the obstruction site.