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

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.

We retrospectively reviewed the records of 479 consecutive patients with acute appendicitis and verified the therapeutic strategy as per the appendicolith and clinical status.

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.

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.