ECE2024 Eposter Presentations Pituitary and Neuroendocrinology (214 abstracts)
1Tokyo Womens Medical University Hospital, Department of Internal Medicine, Tokyo, Japan;2Tokyo Womens Medical University Hospital, Department of Neurosurgery, Tokyo, Japan;3Tokyo Womens Medical University Hospital, Department of Pathology, Tokyo, Japan
Introduction: Acromegaly hardly complicates hypercortisolemia due to co-over-secretion of ACTH from the pituitary tumor. Herein, we present a case of acromegaly with hypercortisolemia.
Clinical case: A 68-year-old woman visited a local clinic due to bitemporal visual field defects. A magnetic resonance imaging scan of the pituitary gland showed a 25 mm-sized mass extending from the sellar to the suprasellar region, and she was referred to our hospital for further evaluation. Physical examination revealed combined features of acromegaly and Cushings disease including cranial ridges, macroglossia, enlargement of the nose and lips, moon face, and central obesity. Her body mass index was 23 kg/m2. Serum levels of hemoglobin A1c, low-density lipoprotein cholesterol, and triglyceride were 5.3%, 104 mg/dl, and 133 mg/dl, respectively. Serum GH and insulin-like growth factor (IGF)-1 levels were 2.59 ng/ml and 238 ng/ml (+2.2 SD) (reference, 60-180), respectively. Serum GH levels were not suppressed (1.77 ng/ml) during a 75 g oral glucose tolerance test. Morning plasma ACTH and cortisol levels were 55.9 pg/ml (reference, 7.2-63.3) and 13.5 μg/dl (reference, 4.0-18.3), respectively. Plasma cortisol levels were suppressed not by 0.5 mg of dexamethasone but by 8.0 mg of dexamethasone, suggesting a coexistence of acromegaly and Cushings disease. Transsphenoidal surgery was performed, and the immunostaining of the excised tumor cells was positive for GH but negative for ACTH. GH and IGF-1 levels were normalized just after the surgery. Although the cortisol levels remained unsuppressed by 0.5 mg of dexamethasone 8 years after the surgery, the case had not exhibited metabolic abnormalities associated with Cushings disease.
Discussion: The co-secretion of GH and ACTH from the pituitary tumor is extremely rare because the expressions of the two hormones are regulated by different transcription factors. However, the endocrinological tests suggested a coexistence of acromegaly and Cushings disease in our case. Pseudo-Cushings syndrome, a condition accompanied by physiologic overactivity of the hypothalamic-pituitary-adrenal axis, displays signs of Cushings disease. The absence of pathological evidence and metabolic impairment of Cushings disease suggested this case as acromegaly with hypercortisolemia associated with pseudo-Cushings syndrome.
Conclusion: We present a case of acromegaly with hypercortisolemia associated with pseudo-Cushings syndrome. The significance of hypercortisolemia might need to be carefully interpreted in patients with acromegaly.