Acute appendicitis remains the most common abdominal surgical emergency in children, with complications such as abscess or appendiceal mass or phlegmon. We hereby report the case of a 10 year –old girl with 17 days of symptomatology consisting of abdominal pain, fever, vomiting and diarrhea. Physical examination revealed the presence of a tender mass over the right lower abdomen, and the diagnosis of appendiceal phlegmon was made. Ultrasonography demonstrated two large appendiceal abscess. Medical management was chosen, using intravenous antibiotics and CT-guided percutaneous drainage with satisfactory results. Literature review reveals two management options: inmediate surgical treatment or initial non-surgical treatment, according to the patient´s condiction. We recommend initial non-surgical treatment for patients with appendiceal abscess or mass, followed by elective appendectomy, to prevent recurrence; the elective operation is associated with low morbidity and mortality.