title: Annular pancreas: a cause of gastric outlet obstruction in a 20-year-old patient.
abstract: BACKGROUND
  Annular pancreas is a congenital anomaly that consists of a ring of pancreatic tissue partially or completely encircling the descending portion of the duodenum. It is formed due to the failure of the ventral bud to rotate, thus it elongates and encircles the upper part of the duodenum. It can present in a wide range of clinical severities, and can affect neonates to the elderly, making it difficult to diagnosis. Although diagnosis of annular pancreas can be made pre-operatively by upper GI series, upper GI endoscopy, or CT scan, 40% of diagnoses require surgery for confirmation.
  
  
  METHODS
  We report the case of a 20-year-old woman presenting with history of vomiting and weight loss since childhood. We present the clinical characteristics, surgical management in the form of bypass procedure done through a duodenojujenostomy, and follow-up of the patient.
  
  
  CONCLUSIONS
  Annular pancreas occasionally presents in adults. Variable presentations have been described in the literature, including pancreatic neoplasm, pancreatitis, obstructive jaundice, duodenal obstruction, and peptic ulcer diseases. Most studies of these lesions are single case reports or small series, which do not allow a surgeon to accumulate extensive experience; therefore, reliance on the combined experience of others in recognition and appropriate management has been the norm.
authors.affiliation: Department of General Surgery, King Faisal Specialist Hospital and Research Center (Gen Org) Jeddah Branch, Jeddah, Saudi Arabia.
authors.forename: Raha
authors.initials: R
authors.lastname: Alahmadi
authors.affiliation: Department of General Surgery, King Faisal Specialist Hospital and Research Center (Gen Org) Jeddah Branch, Jeddah, Saudi Arabia.
authors.forename: Saud
authors.initials: S
authors.lastname: Almuhammadi
mesh_terms: D000714:Anastomosis, Surgical / Q000379:methods; D003937:Diagnosis, Differential; D004386:Duodenum / Q000601:surgery; D016099:Endoscopy, Gastrointestinal; D005260:Female; D015390:Gastric Bypass / Q000379:methods; D017219:Gastric Outlet Obstruction / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery; D006801:Humans; D007583:Jejunum / Q000601:surgery; D010179:Pancreas / Q000002:abnormalities* / Q000601:surgery; D010182:Pancreatic Diseases / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D014057:Tomography, X-Ray Computed; D055815:Young Adult