Low-Dose CT for Right Colonic Diverticulitis an Alternate Diagnosis of Appendicitis

Leesburg, VA, April 8, 2021According to an open-access article in ARRS’ American Journal of Roentgenology (AJR), IV contrast-enhanced 2-millisievert CT (2-mSv CT) is comparable to conventional-dose CT (CDCT) for the diagnosis of right colonic diverticulitis.

“By mitigating concern of missed diagnosis of right colonic diverticulitis, our results further support the use of low-dose CT for suspected appendicitis,” wrote first author Hae Young Kim from the department of radiology at Korea’s Seoul National University Bundang Hospital. “To our knowledge,” Kim et al. maintained, “this is the first study to formally measure the diagnostic performance of CT for right colonic diverticulitis.”

Kim and colleagues’ large pragmatic randomized controlled trial data included 3,074 patients (1,672 women, 1,402 men) aged 15–44 years old (median, 28 years) from 20 hospitals, randomized into 2-mSv (n = 1,535) or CDCT (median, 7-mSv; n = 1,539) groups from December 2013 to August 2016. A total of 161 radiologists prospectively issued CT reports, suggesting alternative diagnoses in 976 (2-mSV CT) and 924 (CDCT) patients. 

In the intention-to-treat analysis, the between-group differences were minute with narrow 95% confidence intervals for most endpoints related to right colonic diverticulitis: test-positives (0.2%; p = .93), test-negatives (0.5%; p = .67), sensitivity (0.0%; p > .99), and specificity (0.2%; p = .66). The characteristics and disposition of test-positive patients were similar between the two groups.
“We believe our results reflect what can be expected in real-word conditions, owing to the pragmatic nature of the trial design, whereby we tried to deliver the intervention with the actual resources used in daily clinical practice,” the authors of this AJR article added.

Founded in 1900, the American Roentgen Ray Society (ARRS) is the first and oldest radiological society in North America, dedicated to the advancement of medicine through the profession of radiology and its allied sciences. An international forum for progress in medical imaging since the discovery of the x-ray, ARRS maintains its mission of improving health through a community committed to advancing knowledge and skills with an annual scientific meeting, monthly publication of the peer-reviewed American Journal of Roentgenology (AJR), quarterly issues of InPractice magazine, AJR Live Webinars and Podcasts, topical symposia, print and online educational materials, as well as awarding scholarships via The Roentgen Fund®.