Streptococcus constellatus is a Gram-positive commensal bacterium of the oropharyngeal, gastrointestinal and urogenital flora. It can cause abscesses in different parts of the body, especially in immunocompromised patients. We present the clinical case of a 33-year-old female patient with a previous history of one anastomosis gastric bypass, among others. The patient was hospitalized two years after surgery for peritonitis secondary to a perforation in the biliopancreatic loop, underwent laparoscopic surgery and was hospitalised for two weeks. Fifteen days after being discharged from the hospital, she went to the emergency service for abdominal pain and fever. An abdominal and pelvic computerized tomography (CT) scan showed a multiloculated pelvic collection with thickened and hypercapillary walls.