Nelson's syndrome post-bilateral adrenalectomy.
Rapid Nelson’s syndrome development after bilateral adrenalectomy is a rare event. A 34-year-old man was referred in 2012 with suspected Cushing's syndrome (CS). Hormonal investigations showed hypercortisolism [serum cortisol 49.2 μg/dl (normal range, NR: 5–25); 24 h urinary-free cortisol, UFC 1903 μg/24 h (NR: <140); serum cortisol after 1 mg dexametasone 23:00 h, 42.1 μg/dl ( N  < 1.8)] with increased plasma ACTH concentration (120 pg/ml; NR: 5–46)]. Magnetic resonance imaging (MRI) of the pituitary gland was normal (Figure 1A). Inferior petrosal sinus sampling (IPSS) with plasma ACTH quantification before and after 100 μg of corticotropin-releasing hormone (CRH) showed no gradient of central/peripheral plasma ACTH both baseline (IPS:peripheral ratio < 2) and post-CRH (IPS:peripheral ratio <3) suggesting ectopic ACTH secretion (EAS). Localizing studies by chest radiography, …