Adrenal incidentaloma: A case of pheochromocytoma with sub-clinical Cushing's syndrome
A 42-year-old female patient was admitted under Department of Gastroenterology with abdominal pain for 1 week. Physical examination was unremarkable. Routine biochemical evaluation including complete blood count, renal function tests (including serum electrolytes) and liver function tests were normal. Abdominal computed tomography (CT) revealed a right supra-renal mass (40 mm × 39 mm × 40 mm), which was heterogeneously enhancing with multiple cystic areas and a homogenously enhancing solid component within the anterior limb of the right adrenal gland. Left adrenal gland was normal []. As per the CT findings, right-sided adrenal adenoma with the possibility of pheochromocytoma was suspected.\nOn endocrine assessment, she had a complaint of intermittent palpitations and headache for 4 years. There was no history of fractures, muscle weakness, easy bruisability, menstrual irregularity and hirsutism. She was on treatment for hypertension and diabetes for 4 years with an adequate control. She was not on any exogenous steroids. On examination, her height was 155 cm, weight was 60 kg, body mass index was 24.97 kg/m2, blood pressure was 130/80 mmHg and pulse rate was 82/min. There were no cushignoid features and hyperpigmentation of skin [].\nHer endocrine investigations revealed raised 24-h urinary metanephrines and nor-metanephrines with value of 3268 μg/24-h (normal range 52-341) and 4591 μg/24-h (normal range 88-444), respectively; raised 8 a.m. serum cortisol with value of 80 μg/dl (normal range 5-25); and normal plasma aldosterone level of 32.84 pg/ml (normal range 34-273). She had non-suppressible serum cortisol of 56.91 μg/dl and 25.86 μg/dl after 1 mg-overnight dexamethasone suppression test (DST) and 48 h - 2 mg/day DST, respectively.\nAfter pre-operative management with alpha and beta blockers, she underwent laparoscopic right adrenalectomy. During the post-operative period, she was watched for hypotension and hypoglycemia, but the entire course remained uneventful. Repeat 8 a.m. serum cortisol on 1st post-operative day was 11.20 μg/dl and she was started on intravenous hydrocortisone 50 mg tid.\nThe excised mass measured 4 cm × 3.5 cm × 3 cm with weight of 12 g. The Pathologist concluded that the lesion was pheochromocytoma staining positive for chromogranin and synaptophysin with hyperplastic adrenal cortex [].\nPatient was discharged on oral prednisolone 5 mg bid. Two weeks later, she was re-evaluated and her 24-h urinary fractionated metanephrines came out to be in normal range and fasting 8 a.m. serum cortisol level was 10 μg/dl (prednisolone stopped 2-day prior to testing). Prednisolone dose was tapered slowly over 2-month and presently; she is not on any medication and doing well.