She went to the hospital early the next morning and was seen by the emergency department physician, who consulted me after the patient's imaging report was obtained. On examination, the patient had a regular heart rate and rhythm, and her abdomen was soft with mild to moderate diffuse abdominal tenderness. Laboratory evaluation revealed a normal complete blood cell count, including a white blood cell count of 5900/μL (to convert to ×109 per liter, multiply by 0.001). Her amylase level was normal at 44 IU/L (to convert to microkatals per liter, multiply by 0.0167) and her lactic acid level was normal at 19.8 mg/dL (reference range, 4.5-19.8 mg/dL; to convert to millimoles per liter, multiply by 0.111). Prothrombin time was elevated at 21.9 seconds, with an international normalized ratio of 2.1. Concerned about an abdominal catastrophe, the emergency department physician ordered an abdominal computed tomographic scan without oral contrast (Figure 1).