Clinical Research Directory

Inclusion Criteria: * Age from 5 to \<15 years-old * Diagnosis of first episode of acute uncomplicated appendicitis confirming the diagnosis: * an increase in the calibre of the appendix, measured at more than 6 mm in diameter and non-compressibility * free fluid, echogenic fat, regional hyperemia * performed in hospital or reviewed by local radiologist investigators if performed outpatient. * Surgery expected within 24 hours after diagnosis * Parental good understanding of the monitoring French instructions * Free and informed consent, signed by both holders of parental authority/legal representative, with the accord of the minor patient. * Affiliation to the health insurance plan Exclusion Criteria: * Ultrasound or CT scan showing one or several stercoliths, a plastron, an abscess or peritonitis * Non-visualization of the appendix at ultrasound or CT scan * Situations contraindicating surgery or anesthesia (patient for whom surgery and anesthesia would pose a life-threatening risk) * Patients who have already received antibiotic therapy for acute appendicitis * Known immunodepression, ongoing immunosuppressive treatment, diabetes * Severe hematologic disorders (such as bone marrow failure, blood clotting disorders) * History of proved allergy to Penicillin * History of proved allergy to amoxicillin and/or clavulanic acid * History of a severe immediate hypersensitivity reaction (e.g. anaphylaxis) to another beta-lactam agent (e.g. a cephalosporin, carbapenem or monobactam). * History of jaundice/hepatic impairment due to amoxicillin/clavulanic acid * History of allergy to any of the excipients listed in section 6.1 of each SmPC. * On going antibiotherapy : previous antibiotherapy have to be stopped at least 48h before inclusion * Parental refusal of research protocol * Impossibility of home follow-up after discharge from hospital * Pregnancy/ breastfeeding * Simultaneously participation in another research study involving medicinal products * Mental state rendering the person giving consent incapable of understanding the trial * Parents being a relative of the investigator or a relative of someone from the team directly involved in the trial, including assistant doctors, pharmacists, nurses, and trial coordinators * Renal insufficiency with creatinine clearance \< 30mL/min * Presence of an appendicolith