5th April 2024

A 66-year-old retired seamstress presents to her GP complaining of new bruising

A 66-year-old retired seamstress presents to her GP complaining of new bruising, headaches and constant fatigue. Tests at the GP surgery reveal a BP of 178/99 mmHg and a BM glucose of 22.5 mmol/L.

Subsequent tests reveal a significantly raised evening cortisol level. The GP arranges an overnight dexamethasone suppression test. After giving 1 mg of dexamethasone at 11pm, the early morning cortisol remains raised. The GP repeats the test but gives 8mg of dexamethasone at 11pm. The following morning cortisol remains significantly elevated. What is the most likely underlying cause of the patient’s symptoms?

Select the SINGLE most appropriate option from the list below. Select ONE option only.