Linear variant of chronic cutaneous lupus erythematosus: a clue for the pathogenesis of chronic cutaneous lupus erythematosus?

Lesions of chronic cutaneous lupus erythematosus usually occur in a discoid pattern as erythematous, well-defined, scaly patches affecting face and scalp. The linear variant of chronic cutaneous lupus erythematosus is an exceptional clinical variation with band-like arranged lesions along the lines of Blaschko which represent the developmental growth pattern of embryonic ectodermal cells. Therefore, this unusual clinical observation may provide additional clues for the pathogenesis of chronic cutaneous lupus erythematosus. It is intriguing to hypothesize that linear lesions of chronic cutaneous lupus erythematosus may be caused by increased susceptibility of resident skin cells due to mutations of genes in early embryogenesis.