Medical Expulsive Therapy for Urinary Stones: Future Trends and Knowledge Gaps

Medical expulsive therapy (MET) for ureteral stones has become a controversial area due to the contradictory results of high-quality trials and meta-analyses.

We aimed to review the literature to evaluate the value of and future directions for MET for ureteral stone disease.

A literature search of the MEDLINE database and the Cochrane Library was conducted to collect articles about MET for ureteral calculi published up to 28 October 2018. A total of 524 articles were screened. Sixty-nine publications that met the inclusion criteria for this review were chosen. Among the primary research articles on MET with stone clearance as the primary outcome, seven responded to high-quality requirements of Cochrane Collaboration's tool for assessing the risk of bias in randomised trials.

The vast majority of randomised, double-blind, placebo-controlled trials without a high or an unclear risk of bias did not find a benefit of MET for increased ureteral stone passage rates. This is in contrast to results of meta-analyses that are skewed by low-quality trials.

The strength of evidence for the benefit of MET in ureteral stones is low, even for distal ureteral stones >5 mm. In the absence of further high-quality data, individual clinicians are required to decide for themselves whether to believe high-quality single trials or meta-analyses.

We evaluated the value of and future directions for medical expulsive therapy (MET) for ureteral stone disease. We found that outcomes varied between studies. Individual clinicians are required to decide for themselves which studies to believe. Alpha-blockers as MET may retain a role in a selective group of well-counselled patients with larger stones who understand the side effects and off-label use.