Lichen planus is not associated with human herpesvirus type 7

increases its skin uptake from circulation and consequently increases mobilization of hepatic and fat stores. Despite this flux to the skin, mobilization of retinol stores may be disproportionate, contributing to the observed increase in serum levels. Only two studies have dealt with the relationship between UVR and serum retinol levels. One involving healthy subjects irradiated for 2 weeks with UVA or broadband UVB did not find variation, and the other with hairless mice showed a transient depletion of serum retinol a few days after a single broadband UVB irradiation. Our data indicate that in patients with psoriasis, vitamin A participates in an adaptive response to NB-UVB exposure; the physiological role of this response needs to be further investigated. It is well documented that vitamin A and RBP4 are involved in lipid metabolism. Subjects with nonalcoholic hepatic steatosis had lower retinol liver stores and an association between obesity and vitamin A deficiency was proposed. We found a negative correlation between BMI and Dvitamin A and we can hypothesize that overweight patients have less adaptive vitamin A response. In agreement with data from higher-latitude regions, we found a high prevalence of vitamin D insufficiency and a substantial benefit of NB-UVB. The limitations of the present study include the absence of a control group, and cutaneous retinol and serum RBP4 levels should be addressed in future studies. In addition to a significant increase of the vitamin D status, NB-UVB increases serum vitamin A levels while clearing psoriasis, the magnitude of this increase being determined by the patient’s BMI.