Endocrine Abstracts

JOINT2064

This is a case report of a 16yo female presenting with pituitary apoplexy, secondary to an ACTH-secreting pituitary macroadenoma. On history, they reported an eighteen-month history of weight gain, hyperphagia and behavioural disturbance requiring psychiatric hospitalisation. Other noted features of Cushing Disease included oligomenorrhoea, acne, hirsuitism, abdominal striae, buffalo hump and acanthosis. She reports subjective visual changes premorbidly, although formal testing was not sought. During this time a clinical diagnosis of polycystic ovarian syndrome and Type 2 Diabetes Mellitus were made, and the patient commenced on metformin 2g daily. Relevant biochemistry included FSH 3IU/l, LH 2IU/l, Estradiol 174pmol/l, testosterone 2.1nmol/l, free testosterone 80pmol/l, progesterone 2.1nmol/l, 17-OHP 0.8nmol/l, OGTT normal. They were reviewed for obesity shortly before presentation with apoplexy. A dexamethasone suppression test one week prior demonstrated an unsuppressed morning cortisol of 550nmol/lwith ACTH not recorded. Other Cushing Disease screening was planned. Past medical history was significant for precocious puberty with thelarche from 5 years of age, and GnRH treatment between 8 and 10.5 years of age. A contrast MRI at 9 years was reported normal with no evidence of pituitary lesion. Tall stature and obesity were present at this time, with a BMI Z-score consistently +2.5 SDs. Following triptorelin cessation they achieved menarche at 12 years of age and was discharged from the endocrinology service. At diagnosis they presented with thunderclap headache, visual loss, nausea and confusion. Apoplexy was demonstrated on CT and MRI. Urgent retrieval and neurosurgical evacuation of haemorrhage and tumour residue was performed, and the patient treated empirically with high-dose steroids. Histopathology confirmed the presence of ACTH-producing pit-NET. The post-operative course was complicated by venous thrombosis, posterior reversable encephalopathy syndrome (PRES), visual impairment, and glucocorticoid withdrawal syndrome. Early assessment of the hypothalamic-pituitary-adrenal axis suggests resolution of Cushing Disease and adrenal gland recovery, however, attempts to reduce post-operative hydrocortisone below 80mg/day (50mg/m²/day) results in significant steroid withdrawal symptoms. Due to this, we are weaning steroids slowly at an increment of 5mg/m²/day every other week. Other pituitary hormone functions are intact, although menses have not yet resumed. Additionally, an oral glucose tolerance test was normal. This case is interesting as both ACTH-secretion macroadenomas and pituitary apoplexy are rare in the paediatric age group. This case highlights the high morbidity associated with such a diagnosis and opens discussion into the importance of considering Cushing Disease in the setting of an increasingly obese population.