The difference between lichen planus and pemphigus vulvae: 1. Lichen planus vulvae is mainly caused by Candida albicans infection that causes localized flaking and itching, while pemphigus vulvae is of unclear etiology but is a precancerous lesion, and the two are different. 2. The treatment of lichen planus vulvae and pemphigus vulvae is also different. However, it can be transmitted to sexual partners through sexual contact. The treatment of pemphigus vulvae requires local application of progesterone ointment and dermaplanin alternatively, or surgery can be done. Pemphigus vulvae is often not contagious through sexual contact, but pemphigus vulvae may lead to atrophy of the vaginal opening after a long period of time.