It wasn’t so long ago that there was absolute consensus on the use of medical expulsive therapy (MET) for the treatment of ureterolithiasis. The 2007 American Urological Association/European Association of Urology combined guidelines decreed the use of alpha-blockers the law of the land for ureteral stones managed by observation.1 Even as recently as 2014, the Cochrane review on the topic was unequivocally in favor of alpha-blockers for MET for ureterolithiasis.2
Now, the evidence has virtually turned on its head.
This comes as no surprise to those who have been following the tale spun by those disavowing the use of tamsulosin. The foundational medical evidence reads like a classic setup for medical reversal. When the 2014 Cochrane review was conducted, it identified 32 studies evaluating the use of MET for ureterolithiasis. Of these, only seven studies had adequate blinding to treatment for physicians and patients. Only six studies reported a mechanism for blinding group allocation. Another eight studies reported outcomes not matching their methods. Most trials involved fewer than 100 patients, were conducted in the Balkans and southeast Asia, and included sponsorship bias. Only two trials were of high-quality and prospectively registered, and these two were among those failing to show a benefit for MET.
The Latest Evidence
However, since that most recent Cochrane review, three significant, high-quality trials assessing the utility of tamsulosin for ureterolithiasis have been published. The first, published in The Lancet in 2015, tested three arms: nifedipine, tamsulosin, and placebo.3 The primary outcome was eventual need for urological intervention, not radiological stone passage. Across all three groups, approximately 20 percent of all participants ultimately underwent urological intervention, with no reliable difference between the groups. Secondary outcomes, such as use of pain medication and days until stone passage, however, relied upon patient self-reporting and were returned in only 62 percent of patients. No differences in the secondary outcomes for analgesic use, time to stone passage, and health status were seen between the three groups.
The next trial, published in the Annals of Emergency Medicine, specifically required follow-up imaging to assess for stone passage.4 Unfortunately, only 78 percent of those enrolled returned for the required 28-day scan, reducing the study’s statistical power. Stone passage was 87 percent in the tamulosin arm versus 82 percent with placebo, with the bulk of the observed difference coming from patients for whom stone size was greater than 5 mm. While there are threats to internal validity with this study and potential subgroups with benefit, these results still further erase the certainty of benefit associated with tamsulosin.