Endocrine Abstracts

Introduction: Double Pituitary adenomas with growth hormone (GH) and adrenocorticotropic hormone (ACTH) secretion are very rare. They are responsible for acromegaly with hypercortisolism. Subclinical corticotropic adenomas are exceptional. Herein, we report the case of a patient with double functional pituitary adenomas causing acromegaly and subclinical Cushing’s disease.

Observation: A 45-year-old woman was referred to our department for suspected acromegaly. Her past medical history included well-controlled diabetes mellitus treated with oral antidiabetic drugs and hypertension. On physical examination, she had a body weight of 65 kg, a body mass index of 26.7 kg/m², a blood pressure of 130/80 mmHg, a heart rate of 72 beats/min, enlarged hands and feet, a large prominent forehead, thickened lips, increased interdental spacing, and prognathism. No signs of hypercortisolism were found. Biological investigations showed an elevated insulin-like growth factor-1 (IGF-1) level at 555 ng/ml (normal range: 81–267), a GH nadir after 75 g oral glucose tolerance test at 2 ng/ml, a morning cortisol level at 158 ng/ml, an ACTH level at 64 pg/ml, a TSH level at 2.26 mIU/l (nr: 0.35–4.94), and a FT4 level at 12.8 pmol/l (nr: 10.6–19.4). Cortisol after the dexamethasone 4 mg suppression test was 86 ng/ml. The diagnosis of acromegaly associated with Cushing’s disease was established. Pituitary magnetic resonance imaging (MRI) showed a pituitary macroadenoma with no clear limits, with heterogeneous signals before and after Gadolinium injection. The patient underwent transsphenoidal tumor resection. The pathological examination revealed two separate pituitary adenomas showing different histological, immunohistochemical, and ultrastructural features. The positivity to ACTH and GH was 100% and 80%, respectively.

Conclusion: This case emphasizes the necessity of an evaluation of all the pituitary axes in case of adenoma in order not to miss a double hormonal secretion or more even in the absence of suggestive clinical signs.