SAT-109 Pituitary abscess presenting as persistent headache in a patient with migraine

Abstract Disclosure: S. Stefan: None. S. Regmi: None. B.Y. Wong: None. Introduction: Pituitary abscess is a rare, but serious intrasellar infection accounting for approximately 1% of all pituitary lesions with a mortality rate that can range from 4.5% to 8%. Clinical presentation is often nonspecific and can include symptoms such as headache, visual deficits and endocrine abnormalities like hypopituitarism. Fever and other signs of systemic infections are less common. We present a case of pituitary abscess from Methicillin Sensitive Staphylococcus aureus (MSSA) that resulted in pan-hypopituitarism and AVP deficiency. Case presentation: A 62-year-old woman with a history of obesity, hyperlipidemia, prediabetes and migraine disorder presented with worsening fatigue and weakness. Symptoms began 8 months prior to presentation and included fatigue, headaches, poor appetite and unexplained weight loss. She was treated for suspected migraine headaches without relief. She denied visual disturbances. On physical exam, she was afebrile and normotensive. MRI pituitary showed a 2 cm centrally hypoenhancing intrasellar lesion with slightextension into the suprasellar cistern, suggestive of necrotic pituitary adenoma or pituitary abscess. Laboratory evaluation was notable for pan-hypopituitarism: cortisol 1.4 (4-20 ug/dL), ACTH 5.1 (7.2-63.3 pg/mL), TSH0.47 (0.3-4.2 uU/mL), FT4 0.4 (0.6-1.5 ng/dL), and FSH 3.1 (<150mIU/mL). WBC count was normal. She was started on hydrocortisone and levothyroxine. Patient underwent trans-sphenoidal pituitary resection, and purulent material was encountered intra-operatively. Tissue culture grew MSSA. She was treated with intravenous ceftriaxone for 6 weeks. There was resolution of her headaches after surgery and antibiotic therapy. However, there was persistent hypopituitarism and AVP deficiency post-operatively. Conclusion: Pituitary abscess is a rare condition. Studies show over half of the cases are culture negative. Staphylococcus aureus is the most commonly identified organism and accounts for about 7.9% of cases. Imaging and laboratory studies usually do not distinguish between adenomas and abscesses, and most patients are diagnosed at the time of surgical exploration. This case highlights the importance of considering intrasellar lesions including pituitary abscess in patients presenting with persistent headaches unresponsive to standard treatment. Prompt recognition and management are crucial to reduce morbidity and mortality associated with this condition. Presentation: Saturday, July 12, 2025