MRCP2-1048

MRCP2-1048

A 23-year-old female with a history of type 1 diabetes mellitus presents with a six-month history of weight loss, anorexia, and fatigue. Her diabetes was previously well controlled with insulin, but she has noticed a decrease in insulin requirement and has experienced hypoglycemic attacks. She has also lost approximately 7 Kg in weight and has been amenorrheic for the last three months. On examination, she is thin with a pulse rate of 70 beats per minute and a blood pressure of 110/70 mmHg with a postural drop. Which investigation is most appropriate for this patient?