Adults suddenly have brown patches on the body may be hyperpigmentation, seborrheic keratosis, lichen planus, chloasma and other diseases.
1. Hyperpigmentation: this disease can be caused by heredity, endocrine disorders, metabolic abnormalities, inflammation and other factors, manifested as brown, black pigmentation and other symptoms.
2. seborrheic keratosis: the cause of this disease is unknown, may be related to skin aging, heredity, sun exposure, air pollution, infection and other factors, manifested as a slightly higher than the skin surface of the light brown flat papules or plaques, the color is light brown, dark brown or even black.
3. lichen planus: this disease is mainly caused by the overpopulation of malassezia bacteria, manifested as brown, light yellow, clear boundaries and the surface of the skin with fine scales and other symptoms.
4. Melasma: this disease is mainly caused by heredity, sex hormone level changes, ultraviolet radiation, chronic diseases, drugs, late night and other factors, manifested as yellowish-brown, dark brown or blackish patches on the skin, aggravated by sunlight irradiation and so on.
It is recommended that patients according to their own situation, if necessary, to the regular hospital dermatology consultation, a clear diagnosis, standardized treatment under the guidance of the doctor.