Pituitary Apoplexy: Don’t Miss the Diagnosis!

Pituitary apoplexy is a rare and potentially lethal endocrine and neurosurgical emer-gency. It is often misdiagnosed or diagnosed late in its course.1 The purpose of this issue of Endocrinology Rounds is to review the pathophysiology of pituitary apoplexy and discuss how to confirm the diagnosis in a timely manner. A case presentation Ms GL is a 45-year-old woman with a past history of hypertension and obesity. One day, she abruptly develops the worst headache of her life and is rushed to the hospital by her family. She has a significantly decreased level of consciousness (Glasgow Coma Scale 7) and is febrile at 40°C. A computed tomography (CT) scan of her head reveals a large pituitary adenoma, but no signs of hemorrhage. Because she is very obese, a lumbar punc-ture and magnetic resonance imaging (MRI) scan cannot be performed. She is treated empirically for sepsis/meningitis with antibiotics. All cultures ultimately come back negative. A cortrosyn adrenocorticotropic hormone (ACTH) stimulation test is done and, at 60 minutes, her cortisol level is 530 µmol/L (the time “0 ” sample was lost). A morning cortisol several days later is only 19 µmol/L and stimulates to only 117 µmol/L, with a