COVID-19 pandemic and adrenals: deep insights and implications in patients with glucocorticoid disorders

Purpose: Coronavirus disease-19 (COVID-19) has spread throughout the world. It was initially defined as a potentially severe syndrome affecting the respiratory tract, but it has since been shown to be a systemic disease with relevant extrapulmonary manifestations that increase mortality. The endocrine system has been found to be vulnerable to COVID-19 infection. The current review aims to evaluate the available data on the impact of COVID-19 infection and treatment, as well as COVID-19 vaccines, on adrenal gland function, particularly in patients with GC disorders. Methods: A thorough search of published peer-reviewed studies in PubMed was performed using proper keywords. Results: Adrenal viral tropism and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replication in the adrenal glands have been demonstrated, and adrenal insufficiency (AI) is a rare, but potentially severe complication in COVID-19 disease, whose recognition can be difficult if only for the empirical treatments administered in the early stages. Glucocorticoid (GC) treatment have had a pivotal role in preventing clinical deterioration in patients with COVID-19, but long-term GC use may increase COVID-19-related mortality and the development of iatrogenic AI. Patients with GC disorders, especially AI and Cushing's syndrome, have been identified as being at high risk of COVID-19 infection and complications. Published evidence suggests that AI patient awareness and proper education may help adjust GC replacement therapy appropriately when necessary, thereby reducing COVID-19 severity. The COVID-19 pandemic has had an impact on AI management, particularly in terms of adherence to patients' care plans and self-perceived challenges. On the other hand, published evidence suggests that the clinical course of COVID-19 may be affected by the severity of hypercortisolism in patients with CS. Therefore, to ameliorate the risk profile in these patients, cortisol levels should be adequately controlled, along with careful monitoring of metabolic and cardiovascular comorbidities. To date, the COVID-19 vaccine remains the only available tool to face SARS-CoV-2, and it should not be treated differently in patients with AI and CS. Conclusion: SARS-CoV-2 infection has been linked to adrenal damage and AI is a rare complication in COVID-19 disease, requiring prompt recognition. Educational efforts and patient awareness may reduce COVID-19 severity in patients with AI. Control of cortisol levels and monitoring of complications may improve the clinical course of COVID-19 in patients with CS.