The non-visualized appendix and secondary signs on ultrasound for pediatric appendicitis in the community hospital setting

Abstract

Secondary signs of appendicitis on ultrasound may aid with diagnosis in the setting of a non-visualized appendix (NVA). This role has not been shown in the community hospital setting. All right lower quadrant ultrasounds performed in children for clinical suspicion of appendicitis over a 5-year period in a single community hospital were evaluated. Secondary signs of inflammation including free fluid, ileus, fat stranding, abscess, and lymphadenopathy were documented. Patients were followed for 1year for the primary outcome of appendicitis. These data were analyzed to determine the utility of secondary signs in the diagnosis of acute appendicitis when an NVA is reported. Six hundred and seventeen ultrasounds were reviewed; 470 of these had an NVA. Of NVAs, 47 (10%) of patients were diagnosed with appendicitis. Sensitivity and specificity of having at least one secondary were 38.3% and 80%, respectively. The positive and negative predictive values of having at least one secondary sign were 17.3% and 92%, respectively. These data suggest that the absence of secondary signs has a strong negative predictive value for appendicitis in the community hospital setting; however, the full utility of secondary signs may be limited in this setting.