Efficacy of phosphodiesterase type 5 inhibitors for the treatment of distal ureteral calculi: A systematic review and meta-analysis

Drugs to affect the smooth musculature of the human ureter - an update with integrated information from basic science to the use in medical expulsion therapy (MET)

PURPOSE

Urolithiasis and symptomatic ureterolithiasis represent diseases known to be on the increase in most westernized countries. The present article aims to give an overview on some drug principles assumed to target signalling systems involved in modulating ureter smooth muscle contractility and to present background to their potential use or prospects in ureter stone disease.

METHODS

The article reviews drugs that have been evaluated over the last decades in vitro, in vivo and/or in clinical settings with regard to their properties to achieve spontaneous passage of (distal) ureteral stones and relieve colic pain. Among these drugs are alpha- and beta-adrenoceptor antagonists, calcium channel blocking agents, Rho kinase inhibitors, nitric oxide (NO) donor drugs, selective inhibitors of cyclic nucleotide phosphodiesterase enzymes (PDEs), as well as potassium channel openers.

RESULTS

Based on the recent scientific information on agents targeting different pathways, antagonists of alpha 1-adrenoceptors, inhibitors of the PDE isoenzymes PDE4 and PDE5 (affecting cyclic AMP- or NO/cyclic GMP-mediated signals that facilitate relaxation of ureter smooth muscle), as well as the combination of certain drugs (for example, PDE5/PDE4 inhibitor plus alpha 1-AR antagonist) seem to be intriguing pharmacological approaches to medical expulsion therapy (MET) in the overall population of patients.

CONCLUSION

While NO donors, calcium channel antagonists and potassium channel openers may be limited for further development for medical expulsion therapy (MET) due to their systemic effects and a lack of effect on stone clearance, Rho kinase inhibitors should be explored further as a future pharmacological principle in ureteral stone disease.

Efficacy and Safety of Boldine Combined with Phyllanthus niruri and Ononis spinosa in Medical Expulsive Therapy for Distal Ureteral Stones with Renal Colic: A Single-Center, Retrospective Cohort Study

Background and Objectives: This study aimed to compare the effects and safety of boldine combined with Phyllanthus niruri and Ononis spinosa plus tamsulosin vs. tamsulosin alone in medical expulsive therapy (MET) for distal ureteral calculi. Materials and Methods: This retrospective cohort study was conducted on 159 renal colic patients with distal ureteric stones (≤10 mm). Patients aged between 18 and 70 years or older with distal ureteral (below the sacroiliac joint) stones ≤10 mm (defined by the largest diameter in three planes) confirmed by urinary ultrasonography and/or native computed tomography (CT). Patients were divided into two groups: A and B. Patients in Group A received tamsulosin 0.4 mg plus boldine combined with Phyllanthus niruri and Ononis spinosa, while those in Group B received tamsulosin 0.4 mg. The rate of stone expulsion, duration of stone expulsion, the dose and the duration of nonsteroidal anti-inflammatory drugs (NSAIDs), analgesic use, and adverse effects of drugs were recorded. Results: No differences were reported in demographic profiles between the two groups. The stone expulsion rate in Group A (84.8%) was higher in comparison to Group B (52.5%); the mean time of stone expulsion was 16.33 ± 4.75 days in Group A and 19.33 ± 6.42 days in Group B. The mean requirement time of analgesia was significantly less in Group A, 2.42 ± 2.56, than in Group B, 6.25 ± 3.05. Drug-related adverse effects (headache, dizziness, nausea, vomiting, postural hypotension, backache, and running nose) were comparable between the two groups. Conclusions: Tamsulosin plus boldine combined with Phyllanthus niruri and Ononis spinosa as medical expulsion therapy is more effective for distal ureteric stones with less need for analgesics and a shorter stone expulsion time than tamsulosin alone.

Pooled-analysis of tadalafil and tamsulosin for ureteral calculi

Objective

Urolithiasis is a common urological diseases and affects the daily life of patients. Medical expulsive therapy has become acceptable for many parents. We conducted a meta-analysis to determine the efficacy and safety of tadalafil compared with tamsulosin for treating distal ureteral stones less than 10 mm in length.

Methods

Related studies were identified via searches of the PubMed, Embase, and Cochrane Library databases. All the articles that described the use of tadalafil and tamsulosin for treating distal ureteral stones were collected.

Results

A total of 14 studies were included in our meta-analysis. Our results revealed that tadalafil enhanced expulsion rate [odds ratio (OR) = 0.68, 95% confidence interval (CI): 0.47 to 0.98, p = 0.04]; reduced expulsion time [mean difference (MD) = 1.22, 95% CI (0.13, 2.30), p = 0.03]; lowered analgesia use [MD = 38.66, 95% CI (7.56, 69.77), p = 0.01] and hospital visits [MD = 0.14, 95% CI (0.06, 0.22), p = 0.0006]. According to our subgroup analysis, either tadalafil 5 mg or 10 mg did not promote expulsion rate and accelerate expulsion time compared with tamsulosin. But patients receiving 5 mg tadalafil decreased analgesia usage [MD = 101.04, 95% CI (67.56, 134.01), p < 0.00001].

Conclusion

Compared with tamsulosin, tadalafil demonstrates a higher expulsion rate and less expulsion time for patients with distal ureteral stones less than 10 mm with a favorable safety profile.

Efficacy of mirabegron for ureteral stones: a systematic review with meta-analysis of randomized controlled trials

Background: Medical expulsive therapy demonstrates efficacy in managing ureteral stones in patients amenable to conservative interventions. This meta-analysis aims to evaluate the effectiveness of mirabegron in the treatment of ureteral stones. Methods: From conception to November 2023, we examined PubMed databases, the Cochrane Library, Embase, Ovid, Scopus, and trial registries for this systematic review and meta-analysis. We chose relevant randomized controlled trials (RCTs) evaluating the efficacy of mirabegron as an expulsive treatment for ureteral stones. The Cochrane risk of bias method was used to assess the quality of the evidence. Outcome measures, which included the stone expulsion rate (SER), expulsion time, and pain episodes, were analyzed using RevMan 5.4 and Stata 17. Results: Seven RCTs (N = 701) had enough information and were ultimately included. In patients with ureteral stones, mirabegron-treated patients had a substantially higher SER [odds ratio (OR) = 2.57, 95% confidence interval (CI) = 1.41-4.68, p = 0.002] than placebo-treated patients. Subgroup analysis revealed that mirabegron was superior to placebo in patients with small ureteral stones (OR = 2.26, 95% CI = 1.05-4.87, p = 0.04), with no heterogeneity between studies (p = 0.54; I2 = 0%). Mirabegron patients had a higher SER than the control group for distal ureteral stones (DUSs) (OR = 2.48, 95% CI = 1.31-4.68, p = 0.005). However, there was no difference in stone ejection time or pain episodes between groups. Conclusion: Mirabegron considerably improves SER in patients with ureteral stones, and the effect appears to be more pronounced for small and DUSs. Nevertheless, mirabegron treatment was not associated with improved stone expulsion time or pain management.

Tamsulosin vs. Tadalafil as medical expulsive therapy for distal ureteral stones: a systematic review and meta-analysis

PURPOSE

Medical expulsive therapy (MET) is recommended for distal ureteral stones from 5 to 10 mm. The best drug for MET is still uncertain. In this review, we aim to compare the effectiveness of tadalafil and tamsulosin for distal ureteral stones from 5 to 10 mm in terms of stone expulsion rate (SER), stone expulsion time (SET) and the side effect profile.

MATERIALS AND METHODS

A comprehensive literature search was conducted on MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Scopus and Web of Science, from inception until April 2023. Only randomized controlled trials were included in the analysis.

RESULTS

Eleven publications with 1,330 patients were included. We observed that tadalafil has a higher SER (OR 0.55, CI 95% 0.38;0.80, p=0.02, I2=52%) and the same efficacy in SET (MD 1.07, CI 95% -0.25; 2.39, p=0.11, I2=84%). No differences were found when comparing side effects as headache, backache, dizziness, and orthostatic hypotension.

CONCLUSION

Tadalafil has a higher stone expulsion rate than tamsulosin as a medical expulsive therapy for patients with distal stones from 5 to 10 mm without differences in side effects.

Is low-dose tadalafil better than tamsulosin? A randomized controlled trial in shockwave lithotripsy for solitary upper tract calculi

OBJECTIVE

To ascertain whether low-dose tadalafil (5 mg) is more efficient than tamsulosin (0.4 mg) in facilitating calculus expulsion in those receiving extracorporeal shockwave lithotripsy for solitary upper urinary tract calculi.

PATIENTS AND METHODS

This was a triple-blinded, prospective, superiority, randomized controlled, single-centre trial. A total of 250 patients with solitary renal or ureteric calculus measuring 6-24 mm were randomized (1:1) to receive either 0.4 mg tamsulosin or 5 mg tadalafil daily for 30 days or until calculus clearance, whichever was earlier.

RESULTS

There was no difference in the primary outcome, namely, calculus expulsion rate at 30 days (tamsulosin vs tadalafil, n (%) 99 [81.1%] vs 98 [80.3%] respectively, 95% confidence interval = 0.8% [-9.0, 10.7], P = 0.874). Similarly, a lack of difference was also noted in the secondary outcome, number of days to expulsion (tamsulosin vs tadalafil, geometric mean [SD] 13.59 [2.39] vs 13.74 [2.39] respectively, P = 0.928). Four patients discontinued the drug due to adverse drug reactions in the tadalafil group.

CONCLUSIONS

Low-dose tadalafil is not superior to tamsulosin in improving calculus expulsion when used as an adjunct to shockwave lithotripsy. In this study, we also noted that tadalafil was less tolerated.

Effect of tamsulosin versus tamsulosin plus tadalafil on renal calculus clearance after shock wave lithotripsy: An open-labelled, randomised, prospective study

Objectives

To compare the efficacy of tamsulosin versus tamsulosin plus tadalafil in achieving clearance of fragments after shock wave lithotripsy (SWL) to treat renal calculi.

Methods

Between January 2016 to December 2017, 140 patients with solitary, non-branched, non-lower calyceal renal calculus and measuring less than 20 mm and treated with SWL were randomized to tamsulosin (group A) or tamsulosin plus tadalafil (group B). Therapy was given for a period of 4 weeks. Stone clearance rate, analgesic requirement, occurrence of steinstrasse, need for auxiliary procedures (endoscopic treatment), and adverse effects of drugs were recorded.

Results

The overall clearance rate was 72.5% (50/69) in the group A and 90.1% (64/71) in the group B (p=0.007). For stones up to 12 mm, the difference in the clearance rate was significant (p=0.039) while it was not so for stones larger than 12 mm (p=0.151). There was no statistically significant difference between the two groups with regards to analgesic requirement (p=0.94), occurrence of steinstrasse (p=0.101), need for auxiliary procedures (p=0.76), and adverse effects of the drugs (p=0.148).

Conclusion

Our study shows that adjunctive medical expulsive therapy with tamsulosin and tadalafil achieves better clearance rate than tadalafil alone in patients receiving SWL for renal stones.

Efficacy of Tamsulosin plus Tadalafil versus Tamsulosin as Medical Expulsive Therapy for Lower Ureteric Stones: A Randomized Controlled Trial

Introduction

Urolithiasis is one of the common disorder with which about 1/5^th is found in the ureter, of which 2/3^rd is seen in the lower ureter. Medical expulsive therapy is one of the routine modalities of treatment which uses various drugs acting on the ureter smooth muscle by different mechanism. We aim to compare the efficacy of combination vs. single drug.

Methods

This randomized controlled trial was done in 176 consecutive patients over a period of six months (March 2019 to August 2019) in Department of Urology and Kidney Transplant Surgery, Tribhuvan University Teaching. Participants were divided into two groups (Group A, tamsulosin plus tadalafil, and Group B, tamsulosin) from computer-generated random numbers. Therapy was continued for a maximum of 3 weeks. Stone expulsion rate, time to stone expulsion, analgesic use, number of colic and emergency room visits for pain, early intervention, and adverse effects of drugs were recorded.

Results

Among 176 patients who were enrolled in study, 7 were lost to follow-up, and 5 people required immediate intervention. There was a significant higher stone passage rate in group A than group B (64 vs. 50; P=0.025) and shorter expulsion time (1.66 vs. 2.32 weeks P=0.001) and less number of emergency room visits and colic episodes. No significant side effects were noted during study.

Conclusion

Tamsulosin plus Tadalafil is more effective than tamsulosin with early passage of stone and decreased number of colic episodes and emergency visits without significant side effects for lower ureteric calculi of 5 mm to 10 mm.

Therapeutic targeting of 3',5'-cyclic nucleotide phosphodiesterases: inhibition and beyond

Phosphodiesterases (PDEs), enzymes that degrade 3',5'-cyclic nucleotides, are being pursued as therapeutic targets for several diseases, including those affecting the nervous system, the cardiovascular system, fertility, immunity, cancer and metabolism. Clinical development programmes have focused exclusively on catalytic inhibition, which continues to be a strong focus of ongoing drug discovery efforts. However, emerging evidence supports novel strategies to therapeutically target PDE function, including enhancing catalytic activity, normalizing altered compartmentalization and modulating post-translational modifications, as well as the potential use of PDEs as disease biomarkers. Importantly, a more refined appreciation of the intramolecular mechanisms regulating PDE function and trafficking is emerging, making these pioneering drug discovery efforts tractable.

Efficacy and safety of phosphodiesterase type 5 inhibitors for the treatment of distal ureteral calculi of 5 to 10 mm in size: A systematic review and network meta-analysis

To evaluate the Efficacy and safety of phosphodiesterase type 5 inhibitors as a medical therapy for distal ureteral calculi by means of a systematic review and network meta-analysis (NMA). We searched the Embase, Medline, and the Cochrane Central Register of Controlled Trials for randomised controlled trials (RCTs) published before May, 2017. Stone passage rate as the primary outcome. We used random effects model for pairwise meta-analyses and Bayesian random effects model for NMA. We evaluated the quality of evidence by the GRADE framework for each network estimate. Five RCTs (861 patients) comparing four different interventions. The results of NMA showed that compared with tamsulosin alone, tamsulosin combined with tadalafil group was associated with significantly higher stone passage rate (odds radio [OR] 2.55, 95% credible intervals [Crl] 1.11 to 5.89). When considering stone expulsion rate, compared with tamsulosin, silodosin was ranked best (OR 3.58, 95% Crl 1.13 to 11.91), followed by tamsulosin combined with tadalafil (OR 2.55, 95% Crl 1.11 to 5.89) and tadalafil alone (OR 1.86, 95% Crl 0.95 to 4.25). No significant difference was found considering safety profiles between any interventions. This meta-analysis indicates that tamsulosin combined with tadalafil is an effective treatment option for ureteral stones with a low occurrence of side effects. Clinicians should take all known safety and compliance of patients into account when choosing an optimal strategy. Since sample size of included studies, further RCTs are strongly encouraged to address the clinical question.

Meta-analysis of the efficacy of sexual intercourse for distal ureteric stones

OBJECTIVE

This meta-analysis was performed to evaluate the efficacy of sexual intercourse for treatment of distal ureteral stones.

METHODS

Randomized controlled trials (RCTs) of sexual intercourse for treatment of distal ureteral stones were searched using PubMed, EMBASE, and the Cochrane Controlled Trials Register.

RESULTS

Three RCTs comprising 240 patients were included in the meta-analysis, which showed that sexual intercourse was effective in treating distal ureteral stones. The expulsion rate of distal ureteral stones at the second week (odds ratio [OR] = 6.61, 95% confidence interval [CI]: 3.66 to 11.94), expulsion rate of distal ureteral stones at the fourth week (OR = 4.00, 95% CI: 2.09 to 7.64), and number of analgesic injections (mean difference [MD] = -0.79, 95% CI: -1.51 to -0.08) indicated that sexual intercourse was more effective than placebo. However, the mean expulsion time of distal ureteral stones (MD = -3.98, 95% CI: -8.77 to 0.81) showed no difference between sexual intercourse and placebo.

CONCLUSIONS

Compared with placebo, sexual intercourse exhibited greater efficacy for the treatment of distal ureteral stones, whilst potentially alleviating pain.

On medical treatment for ureteral stone expulsion

There is evidence that α-adrenoceptor (α-AR) antagonists facilitate the passage of ureteric stones, but the mechanism behind this effect has not been established. If one accepts that it is the friction between a ureteral stone and the mucosa that hampers the passage of the stone, and that the passage traumatizes the mucosa, the aim of treatment must be to reduce this friction. Elevated pressure above an obstructing stone results in an increase in tension in the wall of the upper urinary tract, including the tension at stone level, which causes an increase in friction and ureteric colic. Reducing pressure, by low but adequate fluid intake, non-steroidal anti-inflammatory drugs (NSAIDs), or α-AR antagonists that reduce the friction and give pain relief, seems to be rational. When the stone is pressed downwards by a high pressure the mucosa forms a bar ahead of the stone. These factors reduce the ureteral lumen and hamper the passage of both urine and the stone. The swelling can be reduced by NSAIDs. Filling of the ureter ahead of the stone reduces the friction between the stone and the ureteral mucosa. Evacuation of the urine ahead of the stone by effective peristaltic activity increases this friction. α-AR antagonists that reduce peristalsis may therefore be used to reduce the friction and consequently allow the stones to pass more often and earlier. For very early stone expulsion, a combination of NSAIDs and α-AR antagonists may be useful. There is no evidence that spasm influences the passage of ureteral stones.

Risks of flexible ureterorenoscopy: pathophysiology and prevention

Currently, indications for flexible ureterorenoscopy (fURS) are expanding, mainly due to technological advancements. Although data from clinical series definitely presents fURS as a safe procedure, serious complications including sepsis and ureteral lesions do occur. These complications seem to be a result of the unique elements of fURS, ureteral access and irrigation, pushing normal upper urinary tract physiology into pathophysiological processes, including intrarenal/pyelo-veneous backflow and ureteral contractions, potentially resulting in septic, haemorrhagic and ureteral lesional complications. Knowledge on normal upper urinary tract physiology are crucial for understanding how these harmful effects of fURS may be avoided or minimized. The pathophysiology of intrarenal pressure increases and ureteral access will be discussed as a basis for understanding preventive measures. Role of antibiotics, ureteral access sheaths, safty guidewires, pain medication, prestenting and pharmacologic modulation of pyeloureteral dynamics are reviewed from a pathophysiological perspective.

Sexual intercourse as a new option in the medical expulsive therapy of distal ureteral stones in males: a prospective, randomized, controlled study

PURPOSE

To investigate the effect of sexual intercourse on the spontaneous passage of distal ureteral stones 5-10 mm in size.

METHODS

A total of 190 male patients with distal ureteral stones were randomly divided into three groups. Patients in group 1 were administered tamsulosin 0.4 mg/day (n = 60). Patients in group 2 were asked to have sexual intercourse at least three times a week (n = 66). Patients in group 3 received standard medical therapy alone and acted as the controls (n = 64). The expulsion rate was controlled after 2 and 4 weeks. Differences between the groups were analyzed statistically by the Chi-square and Student's t test. p < 0.05 was considered as statistically significant.

RESULTS

The mean ages of the patients in groups 1, 2, and 3 were 34.4 ± 13.5 (18-60), 38.6 ± 14.1 (18-63), and 36.92 ± 12.4 (18-59) years, respectively (p > 0.05). The mean stone size was 7.09 ± 1.4 mm in group 1, 7.01 ± 1.4 mm in group 2, and 7.1 ± 1.3 mm in group 3 (p > 0.05). Spontaneous passage rates in groups 1, 2, and 3 were 81.6, 81.8, and 51.5%, respectively, and it was significantly higher in group 1 (p = 0.0394) and group 2 (p = 0.0350). There was no significant difference between groups 1 and 2 (p = 0.9925). The analgesic needs in groups 1, 2, and 3 were found to be 1.3 ± 0.4, 1.2 ± 0.6, and 1.4 ± 0.4 times, respectively, and were significantly lower in the sexual intercourse group than in the control group (p = 0.0276).

CONCLUSIONS

Tamsulosin and sexual intercourse increase the spontaneous passage of distal ureteral stones 5-10 mm in size. At least three sexual intercourses per week seem to be at least as effective as tamsulosin. Sexual intercourse also reduces the need for analgesics in ureteric colic due to ureteral stones.