Acne on the chest, back and face is usually a sign of acne, which can be related to heredity, Propionibacterium acnes infection, keratinization of follicular sebaceous gland ducts, androgen-induced sebum secretion, and other factors. Acne, a chronic inflammatory disease that occurs in the sebaceous glands of hair follicles, can be related to a variety of factors such as heredity, Propionibacterium acnes infection, keratinization of the sebaceous gland ducts of hair follicles, androgen-induced sebum secretion, and other factors, and lesions such as acne, inflammatory papules, pustules, and nodules appearing at the opening of hair follicles in many parts of the face, chest, back, and shoulders, often accompanied by enlarged pores as well as sebum overflow. Propionibacterium acnes can cause proliferation and hyperkeratinization of keratin-forming cells at the follicular ducts, leading to obstruction of sebum discharge, resulting in keratin plugs and sebum accumulation to form acne at the follicular opening, and inflammatory papules, pustules and other lesions due to local inflammatory reactions. Acne in many parts of the body, you can go to the dermatology department of the hospital in time for a clear diagnosis, and follow the doctor’s instructions for standardized treatment.