CT Use Reduction In Ostensive Ureteral Stone (CURIOUS).

Area of Science:

• Urology
• Emergency Medicine
• Radiology

Background:

• Computed tomography (CT) is widely used for ureteral stones, but most patients presenting with flank pain do not require hospitalization.
• Hydronephrosis on ultrasound predicts stone presence and complications, though its absence doesn't rule out stones.
• A need exists for a sensitive rule to identify clinically significant ureteral stones.

Purpose of the Study:

• To develop and validate a clinical decision rule to predict clinically important ureteral stones in emergency department patients.
• To identify patients at low risk for ureteral stones, potentially reducing the need for CT scans.

Main Methods:

• Retrospective cohort study of 4000 adult patients undergoing CT for suspected ureteral stones.
• Recursive partition analysis was used to create a clinical decision rule.
• The rule's performance was evaluated using sensitivity, specificity, and predictive values with a 2% risk threshold.

Main Results:

• The final model included hydronephrosis, hematuria, and prior stone history.
• The rule achieved a sensitivity of 95.5% and a negative predictive value of 99.3% for clinically important stones.
• The area under the receiver operating characteristic curve was 0.81, indicating good predictive ability.

Conclusions:

• The developed clinical decision rule can identify low-risk patients, potentially decreasing CT utilization by 63% with a minimal miss rate of 0.4%.
• Further prospective studies are needed to validate the rule's application in broader clinical settings.
• The rule shows promise for optimizing diagnostic strategies in suspected ureteral stone cases.