Factors Affecting the Outcome of Medical Treatment in Cats with Obstructive Ureteral Stones Treated with Tamsulosin: 70 Cases (2018-2022)

Simple Summary

Other than surgical approaches the treatment options for feline ureterolithiasis are limited compared to those of human medicine. After various studies on ureteral muscle relaxation drugs, tamsulosin has been used as a treatment for distal ureteral stones in human medicine. However, the available clinical veterinary data on the efficacy of drugs that relax the ureter are limited. Thus, this study aimed to investigate the factors affecting the outcome of tamsulosin treatment for feline ureterolithiasis. With tamsulosin treatment, the ureteric stone passage was confirmed in 22 out of 70 cats, with a success rate of 31.43%. Negative factors with statistical significance for stone passage in this study were high baseline creatinine levels, female sex, proximal location of stones, and large diameter stones. The results of this study suggest that tamsulosin can be considered for the treatment of ureterolithiasis in cats with small distal ureteral stones. In addition, this study serves as an important reference for determining whether medical treatment of feline ureteral obstruction using tamsulosin can be attempted.

Abstract

The incidence of diseases associated with feline ureteral obstruction is increasing; however, non-surgical treatment options are limited. This study evaluated the outcome of medical treatment in cats with obstructive ureteral stones treated with tamsulosin and identified potential factors predicting spontaneous stone passage. We retrospectively reviewed 70 client-owned cats treated at the Western Referral Animal Medical Center, Seoul, Korea, from 2018 to 2022. All the cats had obstructive ureterolithiasis and were treated using tamsulosin. The baseline characteristics of the cats, stone diameter and location, and stone passage outcomes were analyzed. Stone passage occurred in 22 cats; the remaining 48 cats showed no change in stone locations. Sex, creatinine, and diameter and location of stones were potential risk factors associated with successful stone passage, but age, weight, and side of the stone were not. No serious adverse events related to tamsulosin treatment were observed. This is the first study to identify the risk factors predictive of the spontaneous stone passage of cats with obstructive ureterolithiasis after tamsulosin treatment. Tamsulosin could be an alternative treatment for ureteral obstruction in male cats with smaller distal ureteral stones and low baseline serum creatinine levels. These findings could help develop guidelines for treating feline ureterolithiasis.

Alpha-blockers as medical expulsive therapy for ureteral stones

BACKGROUND

Ureteral colic is a common reason for patients to seek medical care. Alpha-blockers are commonly used to improve stone passage through so-called medical expulsive therapy (MET), but their effectiveness remains controversial. This is an update of a 2014 Cochrane review; since that time, several large randomised controlled trials (RCTs) have been reported, making this update relevant.

OBJECTIVES

To assess effects of alpha-blockers compared with standard therapy for ureteral stones 1 cm or smaller confirmed by imaging in adult patients presenting with symptoms of ureteral stone disease.

SEARCH METHODS

On 18 November 2017, we searched CENTRAL, MEDLINE Ovid, and Embase. We also searched ClinicalTrials.gov and the WHO Portal/ICTRP to identify all published/unpublished and ongoing trials. We checked all references of included and review articles and conference proceedings for articles relevant to this review. We sent letters to investigators to request information about unpublished or incomplete studies.

SELECTION CRITERIA

We included RCTs of ureteral stone passage in adult patients that compared alpha-blockers versus standard therapy.

DATA COLLECTION AND ANALYSIS

Two review authors screened studies for inclusion and extracted data using standard methodological procedures. We performed meta-analysis using a random-effects model. Primary outcomes were stone clearance and major adverse events; secondary outcomes were stone expulsion time, number of pain episodes, use of diclofenac, hospitalisation, and surgical intervention. We assessed the quality of evidence on a per-outcome basis using the GRADE approach.

MAIN RESULTS

We included 67 studies with 10,509 participants overall. Of these, 15 studies with 5787 participants used a placebo.Stone clearance: Based on the overall analysis, treatment with an alpha-blocker may result in a large increase in stone clearance (risk ratio (RR) 1.45, 95% confidence interval (CI) 1.36 to 1.55; low-quality evidence). A subset of higher-quality, placebo-controlled trials suggest that the likely effect is probably smaller (RR 1.16, 95% CI 1.07 to 1.25; moderate-quality evidence), corresponding to 116 more (95% CI 51 more to 182 more) stone clearances per 1000 participants.Major adverse events: Based on the overall analysis, treatment with an alpha-blocker may have little effect on major adverse events (RR 1.25, 95% CI 0.80 to 1.96; low-quality evidence). A subset of higher-quality, placebo-controlled trials suggest that alpha-blockers likely increase the risk of major adverse events slightly (RR 2.09, 95% CI 1.13 to 3.86), corresponding to 29 more (95% CI 3 more to 75 more) major adverse events per 1000 participants.Patients treated with alpha-blockers may experience shorter stone expulsion times (mean difference (MD) -3.40 days, 95% CI -4.17 to -2.63; low-quality evidence), may use less diclofenac (MD -82.41, 95% CI -122.51 to -42.31; low-quality evidence), and likely require fewer hospitalisations (RR 0.51, 95% CI 0.34 to 0.77; moderate-quality evidence), corresponding to 69 fewer hospitalisations (95% CI 93 fewer to 32 fewer) per 1000 participants. Meanwhile, the need for surgical intervention appears similar (RR 0.74, 95% CI 0.53 to 1.02; low-quality evidence), corresponding to 28 fewer surgical interventions (95% CI 51 fewer to 2 more) per 1000 participants.A predefined subgroup analysis (test for subgroup differences; P = 0.002) suggests that effects of alpha-blockers may vary with stone size, with RR of 1.06 (95% CI 0.98 to 1.15; P = 0.16; I² = 62%) for stones 5 mm or smaller versus 1.45 (95% CI 1.22 to 1.72; P < 0.0001; I² = 59%) for stones larger than 5 mm. We found no evidence suggesting possible subgroup effects based on stone location or alpha-blocker type.

AUTHORS' CONCLUSIONS

For patients with ureteral stones, alpha-blockers likely increase stone clearance but probably also slightly increase the risk of major adverse events. Subgroup analyses suggest that alpha-blockers may be less effective for smaller (5 mm or smaller) than for larger stones (greater than 5 mm).

Tamsulosin for treatment of unilateral distal ureterolithiasis: a systematic review and meta-analysis

OBJECTIVES

The lifetime prevalence of ureterolithiasis is approximately 13% for men and 7% for women in the United States. Tamsulosin, an α-antagonist, has been used as therapy to facilitate the expulsion of lithiasis. Whether it is a good treatment for distal lithiasis remains controversial. We conducted a systematic review and meta-analysis to evaluate the effect of tamsulosin on the passage of distal ureterolithiasis.

METHODS

A systematic search was conducted using MEDLINE, EMBASE, and Cochrane Central. Trial eligibility was evaluated by two investigators. All randomized controlled trials (RCTs) comparing tamsulosin to standard therapy or placebo for the treatment of a single distal ureterolithiasis ≤ 10 mm in adult patients with renal colic confirmed by radiographic imaging were included. Data extraction was conducted in duplicate. Primary outcome was the expulsion rate, and secondary outcomes were the mean time for ureterolithiasis expulsion, analgesic requirements, and side effects. Mantel-Haenszel random effect models were used, and heterogeneity was assessed using I² statistics. Data were presented with relative risks (RRs).

RESULTS

The search strategy identified 685 articles, of which 22 studies were included. Combined results suggested a benefit for the expulsion of ureterolithiasis (≤ 10 mm) when tamsulosin was used compared to a standard treatment (RR 1.50 [95% CI 1.31-1.71], I²  =  70%). A decrease in the average time of expulsion of the ureterolithiasis of 3.33 days in favour of tamsulosin was observed (95% CI -4.23, -2.44], I²  =  67%).

CONCLUSION

Tamsulosin increases the rate of spontaneous passage of distal ureterolithiasis (≤ 10 mm).

Alpha-blockers as medical expulsive therapy for ureteral stones

BACKGROUND

Urinary stone disease is one of the most common reasons for patients visiting a urology practice, affecting about 5% to 10% of the population. Annual costs for stone disease have rapidly increased over the years and most patients with ureteral colic or other symptoms seek medical care. Stone size and location are important predictors of stone passage. In most cases medical expulsive therapy is an appropriate treatment modality and most studies have been performed with alpha-blockers. Alpha-blockers tend to decrease intra-ureteral pressure and increase fluid passage which might increase stone passage. Faster stone expulsion will decrease the rate of complications, the need for invasive interventions and eventually decrease healthcare costs. A study on the effect of alpha-blockers as medical expulsive therapy in ureteral stones is therefore warranted.

OBJECTIVES

This review aimed to answer the following question: does medical treatment with alpha-blockers compared to other pharmacotherapy or placebo impact on stone clearance rate, in adult patients presenting with symptoms of ureteral stones less than 10 mm confirmed by imaging? Other clinically relevant outcomes such as stone expulsion time, hospitalisation, pain scores, analgesic use and adverse effects have also been explored.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 9 July 2012 through contact with the Trials Search Co-ordinator using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE and EMBASE, handsearching conference proceedings, and searching the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs), comparing alpha-blockers with other pharmacotherapy or placebo on ureteral stone passage in adult patients were included.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study quality and extracted data. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) and 95% CI for continuous outcomes. Reporting bias was investigated using funnel plots. Subgroup analysis was used to explore possible sources of heterogeneity. Sensitivity analysis was performed removing studies of poor methodological quality.

MAIN RESULTS

Thirty-two studies (5864 participants) were included. The stone-free rates were significantly higher in the alpha-blocker group (RR 1.48, 95% CI 1.33 to 1.64) when compared to standard therapy. Stone expulsion time was 2.91 days shorter with the use of alpha-blockers (MD -2.91, 95% CI -4.00 to -1.81). Use of alpha-blockers reduced the number of pain episodes (MD -0.48, 95% CI -0.94 to -0.01), the need for analgesic medication (diclofenac) (MD -38.17 mg, 95% CI -74.93 to -1.41) and hospitalisation (RR 0.35, 95% CI 0.13 to 0.97). Patients using alpha-blockers were more likely to experience adverse effects when compared to standard therapy (RR 2.74, 95% CI 1.38 to 5.45) or placebo (RR 2.73, 95% CI 1.50 to 4.96). Most adverse effects were mild of origin and did not lead to cessation of therapy, and several studies reported no adverse events in either the treatment or control group.In 7/32 studies patients and doctors were both blinded. In the other studies blinding was not described in the methods or no blinding had taken place. Two studies described incomplete data and only one study showed a relatively high number of patients who withdrew from the study. These factors limited the methodological strength of the evidence found.

AUTHORS' CONCLUSIONS

The use of alpha-blockers in patients with ureteral stones results in a higher stone-free rate and a shorter time to stone expulsion. Alpha-blockers should therefore be offered as part of medical expulsive therapy as one of the primary treatment modalities.

Impact of tamsulosin on ureter stone expulsion in korean patients: a meta-analysis of randomized controlled studies

Purpose

Using meta-analysis, the study's aim was to evaluate the efficacy of tamsulosin, an alpha-blocker, in the treatment of ureteral stones with or without shockwave lithotripsy (SWL) in Korean patients.

Materials and Methods

Relevant randomized controlled studies published through June 2011 were identified in a search of MEDLINE, KoreaMed, and the Korean Medical Database. No language restriction was applied. Only randomized controlled trials conducted with Korean patients were eligible for the analysis. The primary outcome assessed was the stone clearance rate. Two reviewers independently assessed the quality of the study and extracted the data. Meta-analysis was conducted by using R, version 2.13.0.

Results

A total of 6 articles were selected as being suitable for evaluation. Pooling of the trials demonstrated a 43% higher expulsion rate for tamsulosin treatment compared to a control group (risk ratio [RR], 1.43; 95% confidence interval [CI]: 1.24 to 1.65). Similar results were obtained in all subgroup analyses according to stone location (upper: RR, 1.31; 95% CI, 1.02 to 1.68, lower: RR, 1.50; 95% CI, 1.20 to 1.88) or concomitant SWL (yes: RR, 1.38; 95% CI, 1.14 to 1.68, no: RR, 1.48; 95% CI, 1.21 to 1.83).

Conclusions

This meta-analysis of randomized controlled studies provides a high level of evidence supporting the suggestion that treatment with tamsulosin augments the stone expulsion rate for ureter stones with or without SWL in a Korean population. However, a high-quality, large-scale, multicenter, randomized controlled trial is warranted to fully support this hypothesis.

Tamsulosin for ureteral stones: a systematic review and meta-analysis of a randomized controlled trial

BACKGROUND/AIMS

To evaluate the efficacy of tamsulosin as a medical expulsive therapy of ureteral stones.

METHODS

We searched PubMed, EMBASE, the Cochrane Library, and ISI-Science Citation Index up to December 2011. All randomized controlled trials were identified in which patients were randomized to receive either tamsulosin or standard therapy with/without placebo for ureteral stones. Outcome measures assessed were overall stone expulsion rate (primary) and expulsion time, and the number of pain episodes (secondary). Three authors independently assessed study quality and extracted data. All data were analyzed using RevMan 5.0.

RESULTS

Twenty-nine trials with a total of 2,763 patients met the inclusion criteria. The pooled analysis showed a 19% improvement in stone clearance with tamsulosin. According to the doses of tamsulosin, the pooling effects of tamsulosin were analyzed, with a higher expulsion rate obtained than in controls. Compared with calcium channel blockers, there was a higher stone expulsion rate in tamsulosin. In addition, a shorter expulsion time, fewer colic episodes and adverse effects were observed.

CONCLUSIONS

Tamsulosin is a safe and effective medical expulsive therapy choice for ureteral stones. It should be recommended for most patients with distal ureteral stones before stones are 10 mm in size. In future, high-quality multicenter, randomized and placebo-controlled trials are needed to evaluate the outcome.

Effects of alfuzosin with methylprednisolone for spontaneous expulsion and pain control of lower ureteral stone

The aim of this study is to evaluate the efficacy of alfuzosin with methylprednisolone on expulsion and pain control of lower ureteral stones <10 mm in size. Between June 2005 and June 2007, 113 patients with lower ureteral stones <10 mm in size were enrolled in the study. The patients were divided into a control group (group I) and medical expulsive therapy group (group II). Group I (n = 66) received oral analgesics daily and group II (n = 47) received the same analgesics along with 10 mg alfuzosin and 8 mg methylprednisolone for 4 weeks orally once a day. The treatment was continued until stone expulsion or to a maximum of 4 weeks. All patients were allowed 25 mg pethidine hydrochloride intramuscular injections if needed for suboptimal pain control. The average stone size was 6.15 mm in group I and 5.42 mm in group II. Of the 113 patients, 80 became stone free (70.7%). Group II had significantly higher stone free rates (82.9 vs. 62.1%, p = 0.014), fewer expulsion times (mean 4.4 vs. 7.3 days, p = 0.001), and mean number of intramuscular analgesic injections (0.8 vs. 2.1) compared to group I. Alfuzosin with methylprednisolone treatment seems safe and effective for lower ureteral stones <10 mm in size as demonstrated by the increased stone free rate, earlier expulsion, and reduced additional analgesic therapy.

Tamsulosin versus Alfuzosin in the Treatment of Patients with Distal Ureteral Stones: Prospective, Randomized, Comparative Study

Purpose

We evaluated and compared the efficacy of tamsulosin and alfuzosin in the medical treatment of symptomatic, uncomplicated distal ureteral stones.

Materials and Methods

A total of 87 patients with distal ureteral stones of ≤10 mm were randomly divided into 3 groups. Group I patients (n=29) received 0.4 mg tamsulosin daily, group II patients (n=30) received 10 mg alfuzosin daily, and group III patients (n=28) were not given tamsulosin or alfuzosin. Patients in all groups received Diclofenac sodium regularly for 1 week and then on demand. Follow-up was done on a weekly basis for 30 days.

Results

The mean stone size was comparable in the 3 groups (4.97±2.24, 5.47±2.13, and 5.39±1.81 mm, respectively). The stone expulsion rate was 86.2%, 76.6%, and 50% in groups I, II, and III, respectively. The difference in groups I and II with respect to group III was significant (p=0.0028 and 0.035). The mean expulsion time for groups I to III was 7.52±7.06, 8.26±7.34, and 13.90±6.99 days, respectively. The expulsion time was significantly shorter in groups I and II than in group III (p=0.0097 and 0.026). Patients taking tamsulosin and alfuzosin had fewer pain attacks than did group III patients (1.24±0.57 vs. 1.43±0.67 vs. 1.75±1.17). Only 3 cases of drug side effects, 2 in group I and 1 in group II, were recorded.

Conclusions

The use of tamsulosin or alfuzosin for the medical treatment of lower ureteric stones proved to be safe and effective. Moreover, tamsulosin did not have any significant benefits over alfuzosin.

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.

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.