A. Motrenko*a (Ms), I. Komerdusa (Dr), T. Britvina (Prof), I. Ilovayskayaa (Prof), L. Gurevicha (Prof), P. Zakharovaa (Ms)

a Moscow Regional Research and Clinical Institute (MONIKI), Moscow, Russia, Moscow, RUSSIAN FEDERATION

* annettae.leto@gmail.com

Ectopic Cushing Syndrome (EСS) is a rare neuroendocrine disorder, representing about 5-20% of all cases of Cushing's syndrome. ACTH-secreting neuroendocrine neoplasms are usually localized in the thymus, lungs, or gastrointestinal tract, but are rare in the adrenal glands. We would like to present a clinical case of ECS with possible localization in the adrenal gland. Female patient M., 64 years old, noted a prompt progression in muscle weakness, leg cramps, edema of the lower extremities, confusion, and an increase in blood pressure up to 220/110 mm Hg for two months, no other signs of hypercortisolism. Therapist and cardiologist did not found explanation of the clinical symptoms and redirected a patient to an endocrinologist. According to laboratory examination: cortisol (8:00am) 3533.16 nmol/l (101-536), ACTH (8:00am) 124 pmol/l (1.6-13.9), total testosterone 4.62 nmol/l (0.43-1.24), K+ 1.9 mmol/l (4-5.2). According to MRI of the brain and CT of the adrenal glands, no lesions were identified. The presence of ECS was suspected. CT scan of the neck, chest, abdominal and pelvic organs was performed, a focal lesion 9x6mm was found in left lung. Additionally, COVID-19 infection was revealed. Due to the severity of the condition, it was impossible to continue diagnostic procedures and bilateral adrenalectomy was performed for vital indications. In the postoperative period, replacement therapy with prednisolone and fludrocortisone was started, there was an improvement in well-being, normalization of blood pressure and blood potassium and sodium levels. According to the data of histological examination, diffuse hyperplasia of the fascicular zone of the cortical layer of both adrenal glands was revealed. PET-CT with 68Ga-DOTA-TATE was performed, the primary focus was not revealed. Without any specific treatment, the blood ACTH (8:00) level dropped to 37.3 pmol/l (1.6-13.9) within 6 months after surgery. The detailed immunohistochemical study demonstrated diffusely distributed ACTH-producing cells in the medulla of both adrenal glands, thus, we suggest that the adrenal glands were the source of ACTH-ectopic secretion. ACTH concentration above upper normal level can be explained as a physiological reaction to primary adrenal insufficiency.We continue the patient's follow up.

The author has declared no conflict of interest.