What causes erosive lichen planus?
The exact cause of erosive lichen planus is unknown. It is not believed to be an infectious disease. The lesions consist of inflamed skin, but what causes the inflammation is unknown. One theory is that the woman's own immune system is overactive and attacking the skin. Erosive lichen planus may be associated with other auto immune conditions such as vitiligo (white patches on the skin) thyroid disease and alopecia areata (patches of hair loss). | 
