ObjectiveTo evaluate the utility of laboratory ultrasonographic and Doppler ultrasonographic findings in the differentiation of simple and complicated appendicitis.MethodsA prospective study was conducted, including pediatric patients who underwent surgery with the diagnosis of appendicitis.ResultsFifty patients, who were found to have appendicitis on ultrasonographic examination, were included. The mean age was found to be 12.80 ± 3.67 years, with 30% female and 70% male. The patients were histopathologically divided into two groups: simple appendicitis (Group 1, 41 patients, 82%) and complicated appendicitis (Group 2, 9 patients, 18%). CRP (C‐reactive protein) levels (p = 0.004) and periappendiceal fatty tissue thickness (PFI) (p < 0.005) were found to be statistically significantly higher in Group 2 compared to Group 1. The portal vein (PV) diameter and peak systolic velocity (PSV) values were significantly higher in the study group compared to the control group (p = 0.033, p = 0.001).ConclusionDoppler ultrasonographic examination did not significantly differentiate complicated from simple appendicitis. The CRP value is an independent risk factor in the diagnosis of complicated appendicitis, and the presence of a significant increase in mesenteric tissue thickness is one of the important criteria for differentiating complicated appendicitis from simple appendicitis.