Tu1575 Conservative Treatment and Interval Appendectomy for Acute Appendicitis

BACKGROUND Conservative treatment for acute appendicitis (AA) is gradually being adopted as valuable therapeutic choice. Interval appendectomy (IA) after conservative treatment is controversial. OBJECTIVE To clarify the success and recurrence rate of conservative treatment for acute appendicitis, and necessity of IA Patients and Methods We reviewed 503 patients with AA between 2006 and 2013. RESULTS In 503 patients, of which 122 patient undergone emergency appendectomy within 3 days after admission, remaining 381 patients underwent conservative treatment. In 381 patients taken conservative treatment, the success rate of conservative treatment was 98%. Nine patients (2%) were required appendectomy because of progressive disease despite of conservative treatment. After conservative treatment 95 patients (27%) were diagnosed as a recurrent AA at median follow-up 18 months. The predictor for recurrence after conservative treatment was the only following multiple episodes of AA (p=0.002, HR 2.1, 95%CI [1.56-41.1]). The abscess formation and appendicolith did not predict the disease recurrence. At the recurrent AA, 37 of 95 (39%) patients underwent appendectomy including IA. The morbidity of appendectomy for recurrent disease was 5%. Especially the morbidity of IA for recurrent disease was 0%. CONCLUSIONS The success rate of conservative treatment was very high and the risk of recurrence after conservative treatment was 27%. The morbidity of appendectomy for recurrent disease was low (5%). The conservative treatment may be an effective alternative to emergency appendectomy. The routine IA is probably not warranted following successful management of AA, but IA should be required to patients with multiple episodes of AA. Morbidity rate of appendectomy by timing of operation