SUN-426 A Case of Pseudo-Apoplexy: An Unexplored Mechanism of Acute Pituitary Failure

A 70-year old male came in with a 2-week history of drowsiness, generalized body weakness, anorexia, occasional nausea and vomiting that started with a sudden onset of headache during his flight from Michigan, USA to the Philippines without any history of trauma. His headache resolved upon arrival in Manila, however, weakness persisted and he had repeated hyponatremia on hospital consults with essentially normal physical and neurologic findings. Hormonal work-up was done and revealed panhyopituitarism. All symptoms resolved within 2 days of initiating hydrocortisone at physiologic dose. Cranial MRI confirmed presence of a pituitary mass (1.7 x 1.7 x 1.5 cm) with pituitary apoplexy for which the patient underwent endoscopic transsphenoidal transpterygoid surgery. However, histopathology report showed a rathke’s cleft cyst without findings of hemorrhage or infection. Evidences of the dynamic nature of rathke’s cleft cysts have all been clinical, circumstantial and scarce due to the difficulty in diagnosis and documentation. However, cases of acute hypopituitarism in the absence of hemorrhage, infarct, infection or trauma, suggests another pathophysiology of disease that has not yet been extensively reported. This case supports a mechanism of either cyst expansion with encroachment on neighboring structures and/or cerebral edema potentially triggered by changes in atmospheric pressure with international commercial flights flying at approximately 30,000 ft. At higher altitudes, lower partial pressure of oxygen causes relative cerebral hypoxia. Consequently, vascular permeability increases due to the upregulation of vascular endothelial growth factors promoting cerebral edema. This has previously been reported with manifestations more commonly known as acute mountain sickness (AMS) and high altitude cerebral edema (HACE) when associated with life-threatening neurologic deterioration. For patients already with intracranial space occupying lesions, development of minimal edema becomes significant. A slight Increase in mass size or volume of cerebrospinal fluid in smaller spaces such as the sella, are more likely to display symptoms. Therefore, caution should be advised for patients with known intracranial masses who are not to undergo surgery and are planning to travel or stay at high altitudes. Furthermore, rathke’s cleft cysts should be considered as a differential diagnosis to apoplexy-like presentations, especially in those patients who have relatively benign or non-persistent symptoms easily resolving with hormone replacement.