MON-405 Cushing's Disease: An Oligosymptomatic Patient with ACTH-Secreting Pituitary Macroadenoma

BACKGROUND Cushing's disease (CD) is mainly due to pituitary microadenomas producing ACTH. Only 10% of CD presents with macroadenomas. CD is suspected by the presence of classic signs and symptoms and is often associated with metabolic diseases. We present a case of non-classical presentation of CD due to a pituitary macroadenoma CLINICAL CASE 73-years woman with hypertension, diabetes and dyslipidemia in treatment with metformin 850mg bid, insulin NPH 50U/d, Enalapril 10mg bid and Atorvastatin 20mg was referred to endocrinology clinic for noticed in the last year cervical tumor that increases in volume. She noticed occasional headache and decreased visual acuity, denied difficulty in breastfeeding, menopause at 45 years old. Physical evaluation reveals TA 110/60 Weight 82 Kg BMI 39 Central obesity. Thin skin. Abdomen white and thin striae. Nodule in left thyroid lobe 2cm. Muscular atrophy in lower limbs. Absence of reddish striae, hump, skin or mucosa hyperpigmentation, hirsutism and facial plethora. Campimetry by confrontation: bitemporal heteronymous hemianopsia. Blood analysis: Glucose 103mg/dL HbA1C 11.3% Creatinine 1.25mg/dL Total cholesterol 94mg/dl LDLc 40mg/dl Triglyceride 112mg/dl ALT 18 AST 23 TSH 1.83uU/ml (0.27-4.2) Free T4 0.86ng/ml (0.93-1.7). Thyroid US: left nodule 26x20mm with macrocalcifications, irregular edges and central vascularization. FNA Bethesda III. To rule out secondary hypothyroidism, was requested TSH 2.77 Free T4 0.72 FSH 35.6 (48.6-143) LH 14.35 (13-45) Prolactin 9.98 (18-24) Cortisol AM 10.5 (3.7-19.4). A 75ug qd levothyroxine was started 3 months later, she reported headache more frequently, asthenia and difficulty climbing stairs, lower limbs paresthesias, higher dose of insulin was needed (NPH 58U, insulin Lispro 5U before lunch) Glucose 225 HbA1C 14.9% Triglycerides 300 Cortisol AM 9.3ug/dl Cortisol PM 9.7 ACTH(1) 118.1pg/ml (5-63) ACTH(2) 135.8. Free urinary cortisol 76.4ug/24h. Dexamethasone suppression test 2mg/6h by 48h: Cortisol before test was 11ug/dL and after 1.4 Pituitary MRI described a macroadenoma involving the left cavernous sinus and the left carotid artery. After Transsphenoidal surgery, pathology was informed as Pituitary Adenoma, Positive immunohistochemistry ACTH, proliferation index Ki67 1% 1-year post surgery, she had stopped insulin and enalapril. Her only medication is levothyroxine 100ug. Her last blood analysis: Glucose 92 HbA1C 7.2% Creatinine 1.48 Free T4 1.3 FSH 30 LH 16 Prolactin 10.4 Cortisol AM 9.2. CONCLUSION Sometimes, CD can be oligosymptomatic despite being a pituitary macroadenoma, so it can be considered a differential diagnosis in patients with metabolic syndrome REFERENCES Buliman A, et al. Cushing´s disease: a multidisciplinary overview of the clinical features, diagnosis and treatment. J Med Life 2016