Medical expulsive therapy for ureteral stones: where do we go from here?

Despite two decades of clinical use, the effectiveness of medical expulsive therapy (MET) for the noninvasive management of patients with ureteral stones has, in the past year, been called into in question. The primary aim of MET is to expedite stone passage, although it has also shown effectiveness in reducing time to stone passage, thus reducing the incidence of colic episodes, improving stone clearance and improving patients' quality of life. At least 11 systematic reviews and meta-analyses have been published showing clinical benefits of MET; however, the results of these analyses have been challenged by data from two randomized controlled, multicentre trials with large patient cohorts, thus providing higher quality evidence that MET is ineffective in patients with ureteral stones. Results of the various systematic reviews and meta-analyses have suggested that MET is effective, however, such analyses incorporate the biases and limitations of smaller cohort studies, resulting in their conclusions being based upon lower-quality evidence. Evidence for the use of MET for small (<5 mm) distal ureteral stones has weakened based on clinical trial data published in 2015. However, MET might remain effective in the management of larger ureteral stones (>5 mm).