[Reliability of ultrasonography for diagnosing acute appendicitis].

BACKGROUND Abdominal ultrasonography (US) is the most commonly used diagnostic tool for diagnosing acute appendicitis, which is one of the most common causes of acute surgical abdomen. In this study, we examined the reliability of US for diagnosing acute appendicitis. METHODS In this prospective study, we performed abdominal US on 235 patients admitted to our surgical emergency department during 2007 and diagnosed as acute surgical abdomen according to the physical examination and laboratory findings. These patients were surgically treated by appendectomy, and the materials were pathologically examined. RESULTS Two hundred thirty-five patients were admitted to this study. One hundred ninety-three of these patients (82.1%) were diagnosed as acute appendicitis, and 42 (17.9%) were diagnosed differently. One hundred thirty-three (88.67%) of 150 patients diagnosed as acute appendicitis on US examinations were also reported as acute appendicitis on histopathological examination. Sixty of 85 patients diagnosed differently on US examination were reported as acute appendicitis on histopathological examination. CONCLUSION The sensitivity of abdominal US for diagnosing acute appendicitis was determined as 69%. The specificity was calculated as 60%, positive predictive value as 0.89, negative predictive value as 0.30, and accuracy as 0.67. Abdominal US is a helpful diagnostic tool for diagnosing acute appendicitis. However, it should not be seen as superior to anamnesis and physical examination findings.