The Usefulness of Computed Tomography for Patients with Equivocal Acute Appendicitis

ABSTRACT

PURPOSE: We wanted to determine the usefulness of computed tomography (CT) for patients with clinically-suspected but equivocal acute appendicitis, and we wanted to evaluate the differences of the sensitivity and specificity of CT according to the period of time from onset of the signs and symptoms to the performance of CT. METHODS: A retrospective study was done on 273 patients who visited our hospital for acute abdominal pain from Jan. 2003 to Dec. 2005, and they could not be excluded as suffering from acute appendicitis by their symptoms nor signs. RESULTS: Forty-three (15.8%) of the 273 patients did not undergo operation because their condition was not diagnosed as acute appendicitis and 190 patients were diagnosed as acute appendicitis by CT. The other 40 patients underwent diagnostic laparotomy because acute appendicitis could not be confirmed and any other diagnosis could not be made. The patients were classified into 6 groups according to the period of time from the onset of symptoms and signs to the performance of CT. The sensitivity of CT after 48 hours was statistically significantly increased as compared to performing CT before 48 hours (92.3% vs. 75.8%, respectively; P=0.023). CONCLUSION: Forty-three (15.8%) of the patients with clinically- suspected but equivocal acute appendicitis avoided unnecessary laparotomy by undergoing CT. The sensitivity was increased for diagnosing acute appendicitis by CT when it was performed after 48 hours from the onset of symptoms and signs, but caution may be needed during interpretation because of the false positives (2 patients;4.7%) could due to secondary change of other diseases