Does inflammatory linear verrucous epidermal nevus represent a segmental type 1/type 2 mosaic of psoriasis?

BACKGROUND A 6-year-old girl with a symmetric linear eruption on both of her legs, clinically and histologically resembling inflammatory linear verrucous epidermal nevus (ILVEN) or linear psoriasis (LP), with concomitant psoriasis of the guttata type and a positive family history of psoriasis is presented. The questions as to whether LP actually exists and ILVEN represents a distinct entity are still under debate. OBJECTIVE AND METHODS The recent literature concerning case reports of ILVEN and LP is reviewed. RESULTS Case reports of ILVEN and LP can be subdivided into four different groups: (1) ILVEN with or without concomitant psoriasis, only in part reacting to antipsoriatic treatment, (2) ILVEN without concomitant psoriasis, (3) LP with concomitant psoriasis vulgaris, with both groups 2 and 3 reacting successfully to antipsoriatic treatment, and (4) LP without concomitant psoriasis vulgaris and with no family history of psoriasis (very rarely reported). CONCLUSION It is hypothesized that inflammatory linear verrucous eruption besides nevoid psoriasis/LP represents a further segmental type 1/type 2 mosaic of psoriasis which, if a (verrucous) epidermal nevus exists, shows a high affinity of occurrence in close context to such a nevus. Heritability is thought to be possible.