Telangiectasia of nose, numerous streaming Telangiectases in a 56 year old man. A telangiectasis refers to a visibly dilated blood vessel on the skin or mucosal surface. Telangiectases that develop in the absence of any preceding or coexisting cutaneous or systemic disease are considered to be primary or essential. Telangiectases resulting from or in association with a known disease state are classified as secondary. Different presentations of primary telangiectases have been arbitrarily classified as distinct syndromes, designated by terms that often are descriptive based on inheritance, age of onset, anatomic distribution, morphology, prognosis, or associated findings. No recognized nomenclature exists for these telangiectatic disorders. Generalized essential telangiectasia refers to one syndrome of acquired primary telangiectases that are so termed because of their widespread anatomic distribution.