Treatment for Appendicitis With Appendicolith by the Stone Size and Serum C-Reactive Protein Level.

INTRODUCTION:Appendicolith causes acute appendicitis. However, surgical indications for appendicolith-related acute appendicitis have not been established. We aimed to clarify the clinical features of appendicolith-associated appendicitis and determine an appropriate treatment strategy based on the initial presentation. MATERIALS AND METHODS:We retrospectively reviewed the records of 479 consecutive patients with acute appendicitis and verified the therapeutic strategy as per the appendicolith and clinical status. RESULTS:Appendicoliths were identified in 214 of 479 patients (44.6%) using computed tomography. Surgery was more frequently required in patients with appendicolith than in patients without appendicolith (82.7 versus 64.9%; P < 0.001). The stones were smaller and serum C-reactive protein (CRP) concentration was lower among patients with appendicoliths treated with medication alone than among those surgically treated (both P < 0.001). An appendicolith measuring ≤5 mm in diameter and CRP concentration ≤5.36 mg/dL were predictive of completion of nonsurgical therapy. CRP concentration >10 mg/dL and stone diameter of 10 mm were significantly associated with appendiceal perforation. CONCLUSIONS:Nonsurgical therapy could be considered for patients with appendicoliths measuring ≤5 mm in diameter and in cases where the serum CRP concentration is ≤5 mg/dL. An appendicolith measuring >10 mm in diameter or CRP concentration >10 mg/dL is an indication for surgery.