S4492 An Unexpected Neuroendocrine Cause of Persistent Nausea and Vomiting

Introduction: Chronic nausea is a common presenting symptom in gastroenterology clinic, which can be challenging as the etiology is not always gastroenterological. The differential includes metabolic and neurologic disorders such as Meniere's disease, migraines, thyroid dysfunction, and intracranial lesions. A thorough work-up is essential to avoid delays in diagnosis. Case Description: A 40-year-old woman with a history of metabolic dysfunction-associated steatotic liver disease, gastroesophageal reflux disease, class 2 obesity, pre-diabetes, and uterine fibroids was referred for persistent nausea for several years. She reported excessive belching, epigastric pain, and heartburn, with minimal improvement after a 4-week proton pump inhibitor trial. Additionally, she had a 2-month history of 2 to 6 daily episodes of watery, non-bloody diarrhea. In the past 3 weeks, she experienced bilious, non-bloody emesis several times a week, primarily in the morning while fasting and unrelated to meals. She also developed intractable frontal headaches and dizziness. The endoscopic work-up was unrevealing. A recent computed tomography of the head without contrast showed no focal findings. Subsequent magnetic resonance imaging of the brain revealed a prominent T1 hyperintense signal within the pituitary gland, concerning for subacute hemorrhage associated with pituitary apoplexy. The patient was admitted for urgent neurosurgical evaluation. Additional history revealed irregular menstrual cycles, occasional spontaneous bilateral white nipple discharge, and weight gain. Further testing revealed normal thyroid studies, prolactin of 4.58, growth hormone of <0.1, cortisol of 3.11, estradiol of 22.6, and plasma renin activity of 0.681. Neurosurgery recommended against surgical intervention, and steroid replacement was initiated for secondary adrenal insufficiency. After resolution of the nausea, vomiting, and headaches with intravenous hydrocortisone, she was discharged on an oral steroid regimen. Discussion: This case illustrates an atypical presentation of pituitary apoplexy with predominant gastrointestinal symptoms in the absence of classic visual or severe neurological deficits, causing secondary adrenal insufficiency. It highlights the importance of maintaining a broad differential diagnosis, especially in cases with chronic symptoms with limited symptomatic improvement with first-line treatments. Gastroenterologists should maintain a low threshold for ordering brain imaging, especially when there is clinical suspicion for a central etiology of symptoms.