Colonic Diverticulitis Location Affects the Diagnostic Accuracy of Point-of-Care Ultrasound: A Multicenter, 10-Year Study

Abstract

Point-of-care ultrasound (PoCUS) has high sensitivity and specificity in diagnosing uncomplicated colonic diverticulitis in Western patients. Evidence regarding the accuracy of PoCUS in Asian patients in which diverticulitis frequently occurs in the right-side colon is lacking. This multicenter, 10-y study was aimed at evaluating the diagnostic accuracy of PoCUS in various locations of uncomplicated diverticulitis among Asians. A convenience sample of patients with suspected colonic diverticulitis who had undergone computed tomography (CT) were eligible. Patients undergoing PoCUS before CT were included. The primary outcome was the diagnostic accuracy of PoCUS in the various locations, compared with the final diagnosis made by the expert physicians. The sensitivity, specificity, positive predictive value and negative predictive value were computed. The logistic regression model was used to investigate the possible factors related to the accuracy of PoCUS. A total of 326 patients were included. The overall accuracy of PoCUS was 92% (95% confidence interval [CI]: 89.1%-95.0%) and was lower in the cecum (84.3%, 95% CI: 77.8%-90.8%), compared with other locations (p < 0.0001). Nine of 10 false positives had the final diagnosis of appendicitis: 5 had an outpouching structure whose origin in the cecum could not be traced and 4 had elongated "diverticula." Moreover, body mass index was negatively associated with the accuracy of PoCUS in cecal diverticulitis (odds ratio: 0.79, 95% CI: 0.64-0.97) after adjusting for other covariates. Point-of-care ultrasound exhibits high diagnostic accuracy in diagnosing uncomplicated diverticulitis in the Asian population. However, the accuracy varies according to location, and was relatively low in the cecum.