Most urologic professional societies recommend “medical expulsive therapy” for ureterolithiasis, with an expectation of increased stone expulsion, improved time-to-passage, and reduced need for analgesia.
As I’ve covered before – breaking down a pro-tamulosin Cochrane Review – the evidence in support of this practice is junk. David Newman, Anand Swaminathan, and Salim Rezaie agree. The last time I posted, I posited there was probably some small benefit to a subgroup of patient with renal colic, but, alas, we would probably never have high-quality evidence.
I was wrong.
This study in The Lancet tested MET by randomizing patients with CT-confirmed ureterolithiasis to three arms – placebo, nifedipine, or tamulosin. The randomization algorithm balanced the arms between stone size and stone location. The primary outcome was need for urologic intervention at 4 weeks, with secondary outcomes of patient-reported time to stone passage and pain medication use.
With 1,167 patients randomized – 31 of which were excluded or lost to follow-up – there was no difference in need for urologic intervention between groups: 20% placebo, 19% tamulosin, 20% nifedipine. Secondary outcomes – measured by follow-up questionnaire – were likewise similar, with no differences detected in the number of pain medication nor days until stone passage.
Now, urologic intervention is a rather imprecise surrogate outcome for evaluating the efficacy of MET for promoting stone passage. And, only 62% of patients returned the surveys regarding the secondary outcomes of subjective stone passage and analgesic use. This is high-quality evidence, but hardly infalliable. The authors also state no subgroup showed benefit – which is not entirely true. MET was slightly beneficial (86% vs. 82%) for patients with lower ureteral tract stones, with a p-value of 0.099. Giving into the tyranny of p-values, yes, there’s no benefit – but using the p-value akin to a likelihood ratio, judged against the larger context of other (albeit, low-quality) trials showing benefit, I would not find it unreasonable to contest the totality of these authors’ conclusion.
Regardless, the empiric use of tamulosin has simply been an urban legend taken one step too far. Short of large stones in the lower urinary tract, the benefit is fleeting at best – and the magnitude of the benefit may be too low to matter.
“Medical expulsive therapy in adults with ureteric colic: a multicentre, randomised, placebo-controlled trial”