CT imaging history for patients presenting to the ED with renal colic--evidence from a multi-hospital database

Background: Patients with renal colic have a 7% chance of annual recurrence. Previous studies evaluating cumulative Abbreviations: computed tomography (CT) exposure for renal colic patients were typically from single centers.

Methods: This was an observational cohort study. Inner-city ED patients with a final diagnosis of renal colic were prospectively identified (1/10/16-10/16/16). Authors conducted structured electronic record reviews from a 6-hospital system encompassing over 192,000 annual ED visits. Categorical data analyzed by chi-square; continuous data by t-tests. Primary outcome measure was the proportion of study group patients with prior history CT abdomen/pelvis CT.

Results: Two hundred thirteen patients in the study group; 59% male, age 38+/- 10 years, 67% Hispanic, 62% prior stone history, flank pain (78%), dysuria (22%), UA (+) blood (75%). 60% (95% CI = 53-66%) of patients received an EDCV CT; hydronephrosis seen in 55% (95% CI = 46-63%), stone in 90%(95% CI = 83-94%). No significant differences observed in the proportion of EDCV patients who received CT with respect to: female vs. male (62% vs. 56%; p = 0.4), mean age (37+/- 9 years vs. 39+/- 11 years; p = 0.2), and Hispanic vs. non-Hispanic white (63% vs.63%; p = 0.96). Patients with a prior stone history were more likely than those with no history to receive an EDCV CT (88% vs. 16%; p < 0.001). 118 (55%; 95% CI = 49-62%) of patients had at least one prior CT, 46 (22%; 95% CI = 16-28%) had ≥3 prior CTs; 29 (14%; 95% CI = 10-19%), ≥ 10 prior CTs. Patients who did not receive an EDCV CT had a significantly higher mean prior number of CTs than those who had EDCV CT (5.1+/- 7.7 vs 2.2+/- 4.9; p < 0.001). Patients with prior stone were more likely to receive only U/S during EDCV (33% vs. 15%; p = 0.003).

Conclusions: Within our EDCV cohort of renal colic patients, 55% had at least one prior CT. The mean number of prior CTs was lower for patients receiving CT on EDCV, and Ultrasound (US) alone was used more often in patients with prior stone history vs. those with no prior history.