Endocrine Abstracts

Introduction: Hypercortisolism is considered to be a rare condition with an estimated incidence between 0.4 and 2.4 cases per million per year, typically manifests as the clinically and biochemically evident Cushing’s syndrome. However, a more subtle form, known as subclinical hypercortisolism (SH) or autonomous cortisol secretion (ACS), poses diagnostic challenges. It is defined as excessive cortisol secretion without the classic manifestations of clinically overt Cushing syndrome.

Case presentation: We report the case of a 33-year-old female patient, who has been followed for secondary amenorrhea, dyslipidemia, and hypertension since the age of 24, controlled with a triple therapy. Given the secondary nature of hypertension, a CT scan was performed, revealing a right adrenal mass measuring 38x19mm with a spontaneous density of 25 HU. A secretory assessment was conducted: 24-h urinary fractionated metanephrines and vanillylmandelic acid levels were measured ruling out pheochromocytoma. Plasma aldosterone/renin ratio was examined to exclude primary aldosteronism. Regarding hypercortisolism, 24-hour urine free cortisol levels were normal. Additionally, the cortisol circadian rhythm was disrupted with a value of 265 ng/ml. The standard dexamethasone suppression test showed an elevated morning cortisol level at 221 ng/ml (not suppressed). The morning plasma ACTH concentration was low, less than 3 ng/l. The diagnosis of cortisol adenoma was made, hence the indication for adrenal surgery.

Conclusion: Subclinical hypercortisolism is a relatively newly discussed and understood disease. Unfortunately, it is highly under-diagnosed and under-treated. Subclinical Cushing’s syndrome is described as ‘hidden hypercortisolism’ since it is typically asymptomatic. Even though, the condition still leads to long-term consequences of cortisol excess (hypertension, type 2 diabetes, hyperlipidemia and osteoporosis). The timely diagnosis of such cases allows for appropriate management and prevention of associated complications.