Flushing in (neuro)endocrinology.

Cutaneous flushing is a common presenting complaint in endocrine disorders. The pathophysiology of flushing involves changes in cutaneous blood flow triggered by multiple intrinsic factors that are either related to physiology or disease. Flushing can be divided into episodic or persistent causes. Episodic flushing is mediated by the release of endogenous vasoactive mediators or medications, while persistent flushing results in a fixed facial erythema with telangiectasia and cyanosis due to slow-flowing deoxygenated blood in large cutaneous blood vessels. The differential diagnosis of cutaneous flushing in neuroendocrine disorders is limited, yet encompasses a broad spectrum of benign and malignant entities, including carcinoid syndrome, pheochromocytoma, Cushing syndrome, medullary thyroid cancer, and pancreatic neuroendocrine tumors. In this review, we provide a concise and up-to-date discussion on the differential diagnosis and approach of flushing in neuroendocrinology.