Increased permeability of cutaneous lymphatic capillaries and enhanced blood flow in psoriatic plaques

Morphological abnormalities of microvessels are described in psoriasis. However, there are conflicting data as to whether their function is also altered.; Our aim was to study the morphology and function of the lymphatic capillaries of psoriatic skin.; Morphology and permeability of initial lymphatics were studied by microlymphography and densitometry in 20 patients. Perfusion was studied by laser Doppler fluxmetry.; Permeability of lymphatics in plaques was increased by 7.6% compared to unafflicted skin (p < 0.001). Lymphatic vessel density and the extension of dye in lymphatic networks were not significantly different between involved and uninvolved areas. Both sites showed a wide range of diameters of lymphatics. The median laser Doppler flux in plaques was increased by 144% (91-380%) compared to unaffected skin (p < 0.001).; Increased permeability of lymphatics and increased blood flow was demonstrated in vivo in psoriatic skin lesions. These findings may reflect the local inflammatory process and may be used as markers when studying new therapeutic approaches for psoriasis.