[Aggressive course of ectopic ACTH syndrome due to adrenal medulla hyperplasia. Case report].

The article presents a description of a clinical case of an ectopic focus of adrenocorticotropic hormone (ACTH) hypersecretion located in the adrenal medulla in a 64-year-old obese woman without other characteristic clinical signs of hypercorticism, with complaints of rapidly progressing lower limb edema, severe muscle weakness, loss of appetite, weight loss by 4 kg, as well as stage 2 arterial hypertension and type 2 diabetes mellitus. The patient's blood biochemistry showed severe hypokalemia, up to 2.2 mmol/l, despite infusion and oral therapy with potassium preparations. Taking into account the clinical picture and ECG and Echo-CG results, coronary heart disease, functional class II angina, and stage II A chronic heart failure, functional class II according to the New York Heart Association scale were diagnosed. During the laboratory and instrumental examination, endogenous hypercorticism was confirmed, high ACTH values were revealed, there were no visualized pituitary formations - ACTH ectopic syndrome was diagnosed. The patient's severe condition (severe hypokalemia, myopathy, progressive edema of the lower extremities) against the background of the added SARS-CoV-2 infection did not allow for a full topical diagnosis, and therefore the patient underwent a life-saving operation in the amount of bilateral adrenalectomy. In the postoperative period, a significant decrease in the ACTH level was noted, which became the basis for searching for the primary focus of ACTH ectopia in the removed adrenal tissue. According to the results of the immunohistochemical study, ACTH -secreting cells were detected in the medulla of both adrenal glands. This clinical case demonstrates the need for clinical alertness regarding endogenous hypercorticism and demonstrates the uniqueness of the localization of the primary focus of ACTH ectopia.