Pancreatitis and pancreatic disorders — structured clinical encounter

An eight-year-old boy with epilepsy on valproate for three years presents to the emergency department with a two-day history of severe constant epigastric pain radiating to the back, nausea and vomiting. On examination he is tachycardic with marked epigastric tenderness but no guarding. His serum lipase is six times the upper limit of normal and an abdominal ultrasound shows an enlarged, oedematous pancreas with no gallstones. You are the paediatric registrar working through the diagnosis, the early management, the action regarding valproate, and the follow-up plan.