Medical Journal of The Islamic Republic of Iran (MJIRI)

 Abstract

 Background: Misdiagnosis of the acute appendicitis may increase the rate of negative

 appendectomies, which involve a huge waste of resources and are sometimes

 associated with severe complications. Furthermore, false negative result of ultrasonography

 (US) could lead to perforation of appendix. Since ultrasonography is still

 the most common imaging technique used in Iranian appendicitis patients, the study focused

 on evaluate the accuracy of ultrasonograghy in an educational hospital in Iran.

 Methods: We retrospectively reviewed the results of ultrasonograghy in 270 patients

 who referred to Rasoul-e-Akram hospital in Tehran, Iran, between April 2002

 and October 2004 with acute abdominal symptoms suggestive of appendicitis. The

 results of ultrasonography were compared with the histopathologic reports of biopsies

 as a gold standard. In data analysis Chi-square, independent t-test and Mann-

 Whitney U-test were performed.

 Results: The accuracy of ultrasonograghy in acute appendicitis was 60.4% and

 the rate of negative appendectomy was 17.4%. Diagnostic values of US were calculated

 as the sensitivity of 55.4% [95% confidence interval (CI)=48.6-62], specificity

 of 72.3% (95%CI=57.1-83.9), positive predictable value (PPV) of 90.4% (95%CI=

 83.9-94.6) and negative predictable value (NPV) 25.6% (95%CI=18.6-34).

 Conclusion: Although the results of our study implied that the diagnostic values

 of ultrasonography were not considerable, but it is still the only imaging techniques

 available for patients in Iran. In reference to the low NPV, using an alternative technique

 such as abdominal CT scan is recommended. More attention must be paid on

 the signs and symptoms related to acute appendicitis in such patients especially in

 teaching hospitals.