Endocrine Abstracts

Mild autonomous cortisol secretion (MACS) is a state of biochemical hypercortisolaemia with ACTH independence arising in the context of adrenal incidentalomas. There are no external discriminatory features of overt Cushing’s syndrome. 20 to 50% of adrenal incidentalomas are associated with MACS depending on the cut-offs used. The condition is associated with several cardiometabolic comorbidities including diabetes, hypertension, osteoporosis and metabolic syndrome. It is also associated with cardiovascular events and increased mortality. Differentiating between a hyperactive HPA axis and ACTH independence is crucial to make the right diagnosis as a significant number of overnight dexamethasone suppression tests could be false positive and may lead to patient mismanagement. Clinical evaluation and management are ideally undertaken in a multidisciplinary team as management pathways are not always straightforward. Treatment options for MACS include adrenalectomy or medical (conservative) treatment. Surgical studies have shown improvements in metabolic complications especially hypertension and Type 2 diabetes as well as amelioration of low bone mineral density and vertebral fracture risk. Questions persist. Are we referring the right patients for surgery? Is there a role for medical treatment of hypercortisolism in this patient group? How should patients managed conservatively be monitored in the long term? Identifying the best treatment pathway for each patient with MACS is fundamental to reduce morbidity and maybe mortality.