Tinea cruris, also known as sweat spot, is a superficial fungal disease caused by Malassezia infection of the epidermal stratum corneum, and it occurs in young people’s chest and back, face and neck and other sebaceous gland-rich parts. The skin lesions are generally symmetrical or multi-site distribution, varying in size, manifested as a clear border of light red or light brown or even gray-black patches, the surface is covered with a few thin layers of furfuraceous scales, and hypopigmented patches can be left behind after the skin lesions subside. When the body long-term application of glucocorticoids, chronic infections, low immunity, conducive to the growth of the bacteria, can induce this disease. Tinea pedis can be diagnosed by taking the scales in fungal microscopy, which can see short clusters of salami shaped hyphae or clusters of rounded outgrowth spores. The treatment of lichen planus is mainly suitable for topical antifungal drugs, the specific use of dermatologists to consult the main, the area is small, you can use the whole body with ketoconazole bath plus ketoconazole cream topical or sodium thiosulfate topical; if the area is large, the condition of the stubborn can be orally itraconazole (milk to take) or other antifungal drugs. This disease has genetic susceptibility, patients are prone to relapse, daily bathing with ketoconazole can prevent relapse. In short, lichen planus is a common fungal infectious skin disease, patients should go to the hospital in a timely manner, according to the physician’s diagnosis and actively cooperate with the treatment, in order to quickly alleviate the condition.