Capillaropathy and capillaroneogenesis in the pathogenesis of rosacea.

Background: Dilatation of vascular vessels in rosacea has generally been attributed to yielding to deranged connective tissue. In contrast, in a previous study a degrading effect of insufficient vascular vessels in connective tissue has been demonstrated in connection with diabetic microangiopathy. In yet another paper, it was demonstrated that the fusing of damaged capillaries, which had lost part of their adjacent walls due to functional inadequacy, led to the formation of dilated vessels. These pathogenetic patterns are the main subjects of this study of rosacea.

Methods: Punch biopsies from rosacea lesions were examined by light microscopy and immunochemistry in order to identify structural changes leading to the formation of telangiectasias.

Results: Deranged connective tissue is secondary to damaged capillaries. The primary damage may be evoked mostly by environmental influences, mainly the sun.

Conclusions: Infections, infestations, and granulomatous formations are not primary in the development of rosacea.