Unsuccessful Medical Expulsive Therapy: A Cost to Waiting?

To compare clinical outcomes between patients with ureteral stones who underwent an unsuccessful trial of medical expulsive therapy (MET) and patients who did not attempt MET.

We reviewed the clinical records of all potential candidates for MET who were referred from the emergency department to a subspecialty stone clinic.

Of 348 potential candidates, 133 patients (38%) went directly to surgery (NMET) and 215 patients (62%) initiated MET. In the latter group, MET was unsuccessful in 45 patients (21%) (UMET). Stone symptoms were the primary rationale for surgery in 20 (44%) UMET patients and 69 (52%) NMET patients. The UMET patients were more likely to be younger and have smaller, more distal stones than NMET patients. All stones were cleared by ureteroscopy. The average interval from stone clinic assessment to surgery was longer in the UMET patients (17 days) than in the NMET patients (1 day; P <.001). The UMET patients underwent more preoperative computed-tomography scans (2.1) than did the NMET patients (1; P <0.001). There were no differences between the 2 groups in the residual stone burden, pre- or postoperative repeat visits to the emergency department, or repeat surgery.

In this population, we did not observe any detrimental impact of an unsuccessful trial of MET (beyond the additional time and imaging costs). If more confident and effective symptom control could be achieved, expansion of utilization and duration of MET may be a path to improved patient outcomes and cost control.