[Sonography of acute appendicitis. A 5-year prospective study of 2074 patients. 2]

High-resolution real-time ultrasound (US) with a 5 MHz transducer has proved to be an important method in the diagnosis of acute appendicitis. In a prospective study we examined 2074 unselected patients with suspected appendicitis to assess the diagnostic and epidemiological value of US. According to the clinical diagnosis females aged 10 to 30 represented the majority of suspected cases. Appendicitis was most often proved in male patients aged 15-30 years. The prevalence of acute appendicitis in childhood is lower (7%) than in elderly patients (33%). US enables the diagnosis of acute appendicitis with a sensitivity of 91%, a specificity of 98% and an overall accuracy of 97%. For differential diagnosis US demonstrates other diseases that mimic acute appendicitis. Thus it is possible to reduce the negative appendectomy rate particularly in children by revealing mesenteric lymphadenitis or terminal ileitis and in young women by directing attention to gynecological diseases.