Editing AUA: Stone Surgery (2016) (section)

==== Conservative treatment ====
* '''Observation'''
** '''<span style="color:#ff0000">Patients with uncomplicated [any location] ureteral stones <10 mm should be offered observation; </span>[different than 2015 CUA Ureteric Calculi guidelines which suggest intervention for stone >5mm]'''
*** A trial of spontaneous passage is reasonable in patients amenable to conservative therapy with distal ureteral stones <10 mm in whom pain is well controlled and there are no signs of infection or high-grade obstruction.
**** The smaller the stone and the more distally in the ureter the stone is located, the greater the likelihood of spontaneous passage
**** The control arms of RCTs evaluating tamsulosin as MET show that ≈50% of patients with distal ureteral calculi <10 mm in size will spontaneously pass their stones
* '''Medical expulsive therapy'''
**'''<span style="color:#ff0000">Patients with uncomplicated distal ureteral stones <10mm should be offered medical expulsive therapy (MET) with α-blockers </span>[same as 2015 CUA Ureteric Calculi Guidelines]'''
***Ureteral contractility is mediated by both α and β adrenoreceptors in the ureteral wall. Stimulation of α1-receptors promotes contraction of ureteral smooth muscle, leading to more vigorous and frequent peristalsis. α1-antagonists have the potential to inhibit ureteral spasm and uncontrolled contraction, theoretically reducing pain and promoting spontaneous stone passage.
****'''In patients with <10 mm distal ureteral stones, spontaneous stone passage rates improves with α-blockers compared to no treatment (ARR: 23%, 77% α-blockers vs. 54% placebo or no treatment)'''
*****A recent RCT ('''SUSPEND trial''') from the United Kingdom compared tamsulosin (0.4 mg daily), nifedipine (30 mg daily) and placebo (1:1:1) in patients with ≤10 mm ureteral calculi. Unlike most MET trials, the '''primary outcome in this trial was absence of need for additional intervention at 4 weeks rather than radiographic evidence of stone passage.''' There was no difference between groups for the primary outcome. The results of this trial were not incorporated into this Panel’s meta-analysis.
*****Pickard, Robert, et al. "Medical expulsive therapy in adults with ureteric colic: a multicentre, randomised, placebo-controlled trial." The Lancet 386.9991 (2015): 341-349.
***Calcium channel blockers
****Suppress smooth muscle contraction by inhibiting the influx of extracellular calcium into smooth muscle cells
****Insufficient supporting data for the utilization of this agent for MET.
***Patients should be informed that '''medications for MET are prescribed off-label'''
**'''<span style="color:#ff0000">MET can be considered an option in patients with an uncomplicated middle or proximal ureteric calculi <10mm; [2015 CUA Ureteric Calculi Guidelines do not explicitly describe role of MET in these locations]'''
*** No benefit of therapy based on the few α-blocker trials that included patients with middle and proximal ureteral calculi; therefore, use of MET for stones in the middle and proximal ureter could not be specifically endorsed. However, because of the low side effect profile of α-blockers and the demonstrated efficacy of α-blockers in patients with <10 mm stones in any location of the ureter, a trial of α-blockers in a patient with middle or proximal ureteric calculi <10mm, can be considered an option, despite the lack of demonstrable benefit
* '''<span style="color:#ff0000">In most patients, definitive stone treatment should be offered if observation +/- MET is not successful after 4-6 weeks and/or the patient/clinician decide to intervene sooner</span>'''
** '''<span style="color:#ff0000">Indications to proceed with surgical intervention (3):</span>'''
**# '''<span style="color:#ff0000">Pain</span>''': recurrent renal colic requiring repeated visits to the emergency department or hospital admission for parenteral analgesia
**# '''<span style="color:#ff0000">Worsening renal function</span>'''
**# '''<span style="color:#ff0000">Infection:</span>''' evidence of urinary tract sepsis
** A 6-week interval is recommended to reduce the potential for permanent damage. A previous study has also indicated that most stones destined to pass spontaneously will do so within 6 weeks. As such, there seems little benefit in continuing MET beyond this time interval.