Accuracy of Patient Reported Stone Passage for Patients With Acute Renal Colic Treated in the Emergency Department

Abstract

Objective: To study patients who initially presented to the Emergency Department with acute renal colic to determine if patient-reported stone passage detects stone expulsion as accurately as follow-up computed tomography (CT) scan.

Methods: This is a secondary analysis of a multi-center prospective trial of patients diagnosed by a CT scan with a symptomatic ureteral stone <9 mm in diameter. Patient-reported stone passage, defined as capture or visualization of the stone, was compared to CT scan-confirmed passage performed 29-36 days after initial presentation.

Results: Four-hundred-three patients were randomized in the original study and 21 were excluded from this analysis because they were lost to follow-up or received ureteroscopic surgery. Of the 382 remaining evaluable patients, 237 (62.0%) underwent a follow-up CT scan. The mean (standard deviation) diameter of the symptomatic kidney stone was 3.8 mm (1.4). In those who reported stone passage, 93.8% (91/97) demonstrated passage of the symptomatic ureteral stone on follow-up CT. Of patients who did not report stone passage, 72.1% (101/140) demonstrated passage of their stone on follow-up CT.

Conclusions: For patients who report capture or visualization of a ureteral stone, a follow-up CT scan may not be needed to verify stone passage. For patients who do not capture their stone or visualize stone passage, imaging should be considered to confirm passage.

Figure 1.

Participant Flow Diagram