30th April 2024

A 40-year-old woman presents with a 48-hour history of severe, constant right upper quadrant abdominal pain that worsens with movement.

A 40-year-old woman presents with a 48-hour history of severe, constant right upper quadrant abdominal pain that worsens with movement. She reports nausea and has had a fever of 38.2°C. She has a history of intermittent episodes of similar but milder pain over the past year, usually after eating fatty meals. On examination, there is marked tenderness in the right upper quadrant, and she exhibits a positive Murphy’s sign. Her BMI is 30 kg/m^2.

Which investigation is first-line for confirming the diagnosis?