Introduction: In the United States there is debate regarding the appropriate first test for new-onsetrenal colic, with non-contrast helical computed tomography (CT) receiving the highest ratings fromboth Agency for Healthcare Research and Quality and the American Urological Association. This isbased not only on its accuracy for the diagnosis of renal colic, but also its ability to diagnose othersurgical emergencies, which have been thought to occur in 10-15% of patients with suspected renalcolic, based on previous studies. In younger patients, it may be reasonable to attempt to avoidimmediate CT if concern for dangerous alternative diagnosis is low, based on the risks of radiationfrom CTs, and particularly in light of evidence that patients with renal colic have a very high likelihoodof having multiple CTs in their lifetimes. The objective is to determine the proportion of patients witha dangerous alternative diagnosis in adult patients age 50 and under presenting with uncomplicated(non-infected) suspected renal colic, and also to determine what proportion of these patientsundergo emergent urologic intervention.
Methods: Retrospective chart review of 12 months of patients age 18-50 presenting with “flankpain,” excluding patients with end stage renal disease, urinary tract infection, pregnancy and trauma.Dangerous alternative diagnosis was determined by CT.
Results: Two hundred and ninety-one patients met inclusion criteria. One hundred and fifteenpatients had renal protocol CTs, and zero alternative emergent or urgent diagnoses were identified(one-sided 95% CI [0-2.7%]). Of the 291 encounters, there were 7 urologic procedures performedupon first admission (2.4%, 95% CI [1.0-4.9%]). The prevalence of kidney stone by final diagnosiswas 58.8%.
Conclusion: This small sample suggests that in younger patients with uncomplicated renal colic, thebenefit of immediate CT for suspected renal colic should be questioned. Further studies are neededto determine which patients benefit from immediate CT for suspected renal colic, and which patientscould undergo alternate imaging such as ultrasound. [West J Emerg Med. 2015;16(2):269–275.]