[Ultrasound first in acute appendix? Unnecessary laparotomies can often be avoided]

Acute appendicitis is one of the most common causes of acute abdomen. Prospective studies have shown the overall accuracy of the clinical diagnosis to be not more than 70-78% in suspected appendicitis, with a correspondingly high rate of 20-25% unnecessary laparotomies. High-resolution ultrasonography (US) is a readily available, radiation-free noninvasive diagnostic modality that enables visualization of the inflamed appendix and a variety of relevant diseases in the differential diagnostic work-up. Prospective studies have shown that the overall accuracy of US in acute appendicitis ranges between 86 and 87% (sensitivity 75-92%, specificity 92-100%), with positive and negative predictive values of 89-96%, respectively. In experienced hands, US has significantly improved the diagnostic accuracy in suspected appendicitis, while halving the negative laparotomy rate to 8-15%. Since, however, a low percentage of false-negative US explorations due, for example, to accumulation of bowel gas or obesity, final therapeutic decisions be based on a careful consideration of US findings together with history, symptoms and clinical findings.