We present the case of a gallbladder-abscess cavity fistula in a 46-year-old male with walled-off pancreatic necrosis (WOPN). A step-up approach was used for two months, which consisted of a minimally invasive necrosectomy followed by postoperative percutaneous lavages with two drainage tubes. The range of the abscess was significantly reduced, as shown by the computerized tomography scan (Fig. 1). However, a substantial amount of odorless, pale yellow, feculent fluid (almost 1,000 ml daily) was discharged from the drainage tubes over the following days, without lavages.