Study for Clinical Utility of Ultrasound as a Diagnostic Tool in Diverticulitis with Right Lower Quadrant Pain

Ahn, Ji Young; Ryu, Seok Yong; Kim, Hong Yong

Abstract

PURPOSE
Colonic diverticulitis with right lower quadrant pain presents clinical symptoms and signs indistinguishable from those of appendicitis. This study was conducted to evaluate the clinical features, the laboratory findings, and the usefulness of sonography as a diagnostic tool forcolonic diverticulitis.
METHODS
A total of 561 patients with acute right lower quadrant pain was referred for ultrasound (US) examination. The US studies were performed with a 4.0-to 8.0-MHzlinear transducer and an 8.0-to 5.0-MHz convex transducerusing the graded compression method. Thirty-seven (37)patients were finally diagnosed to have diverticulitis. We retrospectively evaluated the age distribution, the sex ratio, the clinical symptoms, the duration of illness before hospital adimission, and the US findings for those 37 patients.
RESULTS
The average age of the patients was 33+/-16.1 years old. The ratio of males to females was 1.1 : 1. The mean duration of illness prior to seeking medical attention was 49.2+/-9.3 hours. Nausea, vomiting, and anorexia were seen in 29.7%, 10.8%, and 27.0% of the patients, respectively. Sonography detected 30 patients with diverticulitis with 2 false positive and 7 false negative results. The most typical sonographic feature of an inflamed diverticulum was a round or oval-shaped hypoechoic structure (86.5%) protruding from the colonic wall. Regional pericolic or peridiverticular fat thickening was noted in 81.1% of the patients, and segmental colon wall thickening in 70.8%. US examination yielded a sensitivity of 81.1%, a specificity of 99.6%, an overall accuracy of 98.4%, a positive predictive value of 93.7%, and a negative predictive value of 98.7%.
CONCLUSION
This study will be useful in the diagnosis of right colonic diverticulitis, in particular, by using abdominal sonograms in patients who have atypical clinical symptoms or signs of appendicitis.