MON-049 Hormonal Havoc: When Sweet Turns Sour- A case Report of Growth Hormone Secreting Macroadenoma Driving Uncontrolled Type 2 Diabetes Mellitus

Abstract Disclosure: B. Zaidan: None. S. Khalid: None. M. Pennant: None. Introduction: Acromegaly, a rare endocrine disorder caused by excess growth hormone (GH), is typically due to a pituitary adenoma. It is associated with metabolic, cardiovascular, and neurological complications, including a 20-50% prevalence of type 2 diabetes mellitus (T2DM) (1,2). Pituitary apoplexy, occurring in 2-12% of adenoma cases, results from hemorrhage or infarction and can sometimes normalize hormone secretion (3). This case report details a 64-year-old woman with uncontrolled T2DM and acromegaly who experienced significant diabetes improvement following pituitary apoplexy. Case Presentation: A 64-year-old female with a past medical history of uncontrolled type 2 diabetes mellitus (T2DM) presented to the emergency room with new-onset headache, nausea, vomiting and MRI of the brain revealed a 3.4 cm seller/suprasellar mass exerting mass effect on the optic chiasm consistent with pituitary macroadenoma. She recalled experiencing increasing show and ring size. Hormonal work up at the time revealed IGF-1 elevated at 557 ng/mL (normal range: 41 - 279 ng/mL), ACTH 8 pg/mL (range 6-60 pg/mL), Free T4 1.2 ng/dL (0.8-1.8) and cortisol level of 11.8 mcg/dL. A week later she was noted to have diplopia and marked right abduction deficit indicative of CN VI palsy. MRI at the time revealed increase size of the mass with cavernous sinus invasion, mass effect of optic chiasm and new internal foci of T1 hyper-intensity suspicious for apoplexy. Repeat IGF-1 level at that time was normal at 182 ng/mL (normal range: 41 - 279 ng/mL) along with low FT4 of 0.7 ng/dL and cortisol of 4.3 μg/dL. She eventually underwent transsphenoidal resection of the tumor. Histopathological examination confirmed a neuroendocrine tumor secreting IGF-1 characterized as a densely granulated somatotroph tumor. She had poorly controlled diabetes pre-operatively with HbA1c of 11.8% that improved to 9% after apoplexy and post operatively her A1c normalized to 5.3% and she was taken off all diabetes medications. Conclusion: Diabetes in patients with acromegaly is associated with increased overall and cardiovascular mortality and morbidity (2,4). This case underscores the critical role of recognizing underlying conditions, such as acromegaly, that contribute to resistant type 2 diabetes mellitus (T2DM). The excess growth hormone played a key role in the patient's uncontrolled T2DM, as evidenced by a significant reduction in HbA1c and blood glucose levels following her presentation with apoplexy. Timely diagnosis and appropriate surgical intervention can lead to substantial metabolic improvement and even resolution of diabetes. However, the potential for postoperative complications, such as diabetes insipidus, highlights the necessity of vigilant monitoring and comprehensive management to optimize patient outcomes. Presentation: Monday, July 14, 2025