Left psoas abscess due to duodenal fistula as a late complication of necrotizing pancreatitis treated by endoscopic approach.

Gastrointestinal fistulas can be a complication of severe acute pancreatitis, and their incidence is low and sporadically reported in the literature. The most frequently reported site is in the colon, followed by duodenal fistulas. Psoas abscess is a rare condition. Iliopsoas abscesses are classified as primary or secondary. Secondary abscesses develop by spreading infection from contiguous anatomical structures, such as the gastrointestinal tract. We present the case of a recurrent left psoas abscess secondary to a duodenal fistula as a late complication of necrotizing pancreatitis resolved by endoscopic treatment.