Medical Expulsive Therapy of Single Distal Ureteral Stones

Medical Expulsive Therapy of Single Distal Ureteral Stones. A Randomised, Double-blind and Placebo-controlled Study

Current therapeutic options for ureteral stones include active intervention as well as conservative "watch and wait" approaches. Endoscopic treatment of ureteral stones has a high success rate and reliably results in immediate stone removal However, surgical as well as anaesthetic risks are not negligible and serious complications are possible. For many patients, a conservative treatment is an appealing option. Watchful waiting, however, not always results in stone clearance and may be associated with recurrent renal colics. The therapeutic potential of alpha-blockers for ureteral stone disease has been investigated prompted by the detection of alpha-receptors in ureteral smooth muscle cells. Blocking of such receptors, which are predominantly located in the distal part of the ureter results in relaxation of the ureteral wall and modulation of peristaltic activity. This mechanism has been proposed to facilitate stone passage for ureteral calculi. Numerous clinical trials have revealed a significant improvement of the stone expulsion rate using the alpha-blocker tamsulosin. Most of these studies were randomised but none were performed in a double-blind and placebo-controlled fashion. Therefore, the objective of this trial was to evaluate the efficacy of medical expulsive therapy with tamsulosin in a randomised, double-blind, placebo-controlled setting.

The primary end point was the number of patients per group experiencing stone expulsion until day 21, as confirmed by low-dose abdominal computed tomography (CT).

The patient-defined time of stone expulsion was considered the event for time to stone passage. Patients with unnoticed stone expulsion were censored at the date of last positive stone status, and those who discontinued the therapy were censored at the date of last medication intake. Kaplan-Meier estimates were computed for time to stone passage.

Oral diclophenac (up to 3x50 mg pills) as first-line and oral metamizole (up to 8x 500mg pills)as second-line on-demand analgesics were prescribed. All patients were requested to record the required amount of pills per day

All patients kept a diary to record the score of every painful episode on a 10-cm visual analogue scale (0= no pain at all; 10= strongest pain one can imagine).

The number of participants requiring active treatment was recorded. Shock wave lithotrypsy (SWL), ureterorenoscopy (URS) or insertion of an ureteral catheter were considered as active treatment.

Inclusion criteria: patients with a single 2 to 7mm ureteral stone below the common iliac vessels Exclusion criteria: presence of multiple ureteral stones renal insufficiency (glomerular filtration rate below 60 ml/min) urinary tract infection a solitary kidney pregnancy history of ureteral surgery or previous endoscopic procedure hypersensitivity to tamsulosin current alpha-blocker, calcium-antagonist or corticosteroid medication

Hermanns T, Sauermann P, Rufibach K, Frauenfelder T, Sulser T, Strebel RT. Is there a role for tamsulosin in the treatment of distal ureteral stones of 7 mm or less? Results of a randomised, double-blind, placebo-controlled trial. Eur Urol. 2009 Sep;56(3):407-12. doi: 10.1016/j.eururo.2009.03.076. Epub 2009 Apr 3.