RESUMEN
BACKGROUND: Retroperitoneal abscesses are rare complications of intraabdominal infectious processes and can progress to necrotizing infections. Necrotizing pancreatitis occurs in 10-25% of patients that require hospital admission for pancreatitis, is associated also with a 25% mortality rate, and may lead to formation of a retroperitoneal abscess. CASE REPORT: We report a case of a 63-year-old woman with a recently resolved case of pancreatitis who presented to the Emergency Department (ED) with a painful nodule on her left flank for 3 weeks, rapidly progressing over the last 12 h. In the ED, examination revealed an expanding area of erythema over the left flank with sepsis. Computed tomography scan revealed necrotizing pancreatitis with retroperitoneal abscess tracking to the abdominal wall, resulting in necrotizing fasciitis. She was taken emergently to the operating room with a good outcome. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Acute pancreatitis is common, with a minority of cases resulting in parenchymal necrosis, which can lead to retroperitoneal infections. Rarely, necrotizing fasciitis can present on the abdominal wall as a complication of intraabdominal or retroperitoneal infections. The emergency provider should be aware of these complications that may lead to necrotizing infections and a potentially indolent course.