Patient: Male, 51Final Diagnosis: Oxidised cellulose retainSymptoms: Abdominal pain • nausea • vomitingMedication: —Clinical Procedure: Laparoscopic abdominal exploration and drainageSpecialty: SurgeryObjective:Challenging differential diagnosisBackground:Bleeding is a major intraoperative complication during surgical procedures. When conventional methods such as ligature and diathermocoagulation are ineffective for bleeding management, hemostatic agents should be used. Oxidized cellulose is one of the major hemostatic agents used worldwide. Oxidized cellulose is often left in situ after hemostasis because of its high level of reabsorption that lasts up to 8 weeks. However, 38 cases of retaining-associated complications are reported in the literature.Case Report:A 51-year-old male patient presented in our emergency department with acute abdominal pain, nausea, and vomiting. The patient had been admitted in our department for laparoscopic cholecystectomy for acute cholecystitis 25 months previously. Abdominal ultrasound and CT scan showed the presence of a cystic circular mass, with homogeneous fluid content, close to the surgical clips of the previous surgery, resembling a “neo-gallbladder”. Laparoscopic abdominal exploration and drainage were performed. Histological examination reported protein-based amorphous material with rare lymphocytes and macrophages. Culturing was negative for bacterial growth. The patient was discharged uneventfully on the 4th postoperative day. The primary surgical report was evaluated with evidence of application of Gelita-Cel® Standard for hemostatic purposes. Results of 12-month follow-up were normal.Conclusions:Herein, we report the first case of a complication associated with the use of Gelita-Cel® Standard. We reviewed the literature to better define the purpose and limits of oxidized cellulose use as a hemostatic agent. Despite the fundamental role of oxidized cellulose as a hemostatic agent, we provide some practical suggestions to prevent the reported severe complications and surgical overtreatments.