New morphological findings in so-called negative appendectomies.

Appendices of children operated on because of clinical signs of acute appendicitis and presenting normal histological findings were revised by means of special assays. These findings were then compared with appendectomies during abdominal surgery, catarrhal and early phlegmonous appendicitis. We found pathological changes of the epithelium and the lymphatic tissue in more than two thirds of the specimens originally classified as normal. Therefore the term of "negative appendectomy" has to be redefined.