USMLE题库Endocrinology1-10.pptx

Endocrinology 题库 Q 1 A 50-year-old male presents to the emergency room with a sudden severe headache, double vision, and bitemporal hemianopsia. He says that he’s had decreased libido and mild headaches for a few months. As you are presenting to your attending，he develops cardiovascular collapse and dies，despite aggressive resuscitation. Autopsy will most likely reveal which of the following? Rupture of berry aneurysm Pituitary hemorrhage Pulmonary embolism Ischemic necrosis of pituitary Acute congestive glaucoma Temporal arteritis A 1: Correct answer: B The patient described in the vignette most likely had pituitary apoplexy, which is acute bleeding in to a preexisting pituitary adenoma. Pituitary apoplexy is a medical emergency; without treatment, prognosis is poor. Symptoms will be bimodal; acute and chronic. The long-standing symptoms of a pituitary tumor will be present for months, as with this mans headache and decreased libido; accompanying these chronic symptoms will be an acute presentation, as with the severe headache and visual disturbances in this patient. Signs of meningeal irritation can also be seen in pituitary apoplexy, mimicking a subarachnoid hemorrhage. A careful physical exam can differentiate a subarachnoid hemorrhage from a sellar mass with suprasellar extension (pituitary tumor) by the presence of bitemporal hemianopsia, present only in the latter. Patients suffering from pituitary apoplexy develop cardiovascular collapse because ACTH deficiency leads to adrenocortical insufficiency. An urgent neurosurgical consultation and treatment with glucocorticoids are required. (Choice A) The rupture of berry aneurysm can present similarly to pituitary apoplexy, including signs of meningeal irritation and cranial nerve palsy. As discussed previously, these conditions can be differentiated by bitemporal hemianopsia, which is specific to pituitary lesions. An MRI of the brain will be very sensitive in diagnosing either condition. (Choice C) Pulmonary