Imaging in Suspected Renal Colic: Systematic Review of the Literature and Multispecialty Consensus

Study objective: Renal colic is common and computed tomography (CT) is frequently used when the diagnosis of kidney stone is suspected. CT is accurate but exposes patients to ionizing radiation and has not been shown to alter either interventional approaches or hospital admission rates. This multiorganizational transdisciplinary collaboration seeks evidence-based, multispecialty consensus on optimal imaging across different clinical scenarios in patients with suspected renal colic in the acute setting. Methods: In conjunction with the American College of Emergency Physicians (ACEP) Emergency Quality Network, we formed a 9-member panel with 3 physician representatives each from ACEP, the American College of Radiology, and the American Urology Association. A systematic literature review was used as the basis for a 3-step modified Delphi process to seek consensus on optimal imaging in 29 specific clinical scenarios. Results: From an initial search yielding 6,337 records, there were 232 relevant articles of acceptable evidence quality to guide the literature summary. At the completion of the Delphi process consensus, out of the 29 scenarios agreement was rated as perfect in 15 (52%), excellent in 8 (28%), good in 3 (10%), and moderate in 3 (10%). There were no scenarios in which at least moderate consensus was not reached. CT was recommended in 7 scenarios (24%), with ultrasonography in 9 (31%) and no further imaging needed in 12 (45%). Conclusion: Evidence and multispecialty consensus support ultrasonography or no further imaging in specific clinical scenarios, with reduced-radiation-dose CT to be used when CT is needed for patients with suspected renal colic.