A girl with gastric distension and hyperamylasemia

A 3-year-old girl was admitted with abrupt onset of acute severe abdominal pain and drowsiness, without vomiting or diarrhoea. No history of abdominal trauma was reported. On admission, she was moaning, her heart rate was 161 bpm, blood pressure was 108/72 mm Hg, capillary refill time was <2 s and she was apyrexial. On physical examination, there was marked abdominal distension, with generalised abdominal tenderness without peritoneal signs. Blood tests showed hyperamylasemia (780 IU/L), neutrophilia (white cell count 14×10^9/L; neutrophil 11.9×10^9/L) and hyperglycaemia (155 mg/dL–8.6 mmol/L). A supine plain abdominal X-ray showed a huge gastric bubble (figure 1). A nasogastric tube was inserted, and 500 mL of non-bilious fluid and 150 mL of gas were suctioned, with prompt improvement of symptoms. Figure 1 Huge gastric bubble; patient lying supine. 1. Which of the following is the most common cause of hyperamylasemia …