Background: Ever since the first appendectomy has been performed, surgery has been the standard of care for acute appendicitis, with antibiotic therapy being reserved for special situations. Recent studies have shown the feasibility of antibiotic therapy for uncomplicated appendicitis. Methods: This clinical therapeutic review is based both on author expertise and a selective literature survey in PubMed based on the term ‘appendicitis', combined with the terms ‘acute', ‘complicated', ‘conservative', ‘non-operative', ‘therapy', ‘surgery', and ‘strategy'. According to these search results as well as to the treatment guidelines from the American College of Surgeons, Society for Surgery of the Alimentary Tract, Society of American Gastrointestinal and Endoscopic Surgeons, European Association of Endoscopic Surgery, and World Society of Emergency Surgery, we present an interdisciplinary treatment concept. Results: Approximately 90% of patients treated with antibiotics are able to avoid surgery during the initial admission. The other 10% that fail to respond to antibiotics require a rescue appendectomy. Recurrence rates of non-operated patients within 1 year are as high as 20-30%. Conclusion: In uncomplicated appendicitis without risk factors for failure of non-operative management, a shared decision based on the patient's preferences should be made. In cases with risk factors, appendectomy is still the treatment recommended. If the diagnosis is uncertain or clinical symptoms are rather mild, antibiotic therapy should be started. In complicated appendicitis, management depends on the clinical state, with either immediate surgery or primarily antibiotic therapy and combined with drainage of abscess, being followed by interval appendectomy in some cases.

Keywords:
Abdominal infections, Acute appendicitis, Antibiotic therapy, Complicated appendicitis, Laparoscopic surgery
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2018
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