There are so many small red bumps on the back, which may be acne, eczema, and of course, folliculitis. Acne is due to the large number of hair follicles and sebaceous glands in this area of the tissue structure, coupled with the fact that if the patient often stay up late or lack of sleep, the local hygiene is not too good, it is easy to induce the occurrence of acne. Of course, there is also a possibility of folliculitis, folliculitis is localized in the back of the skin of the hair follicles appear inflammatory reaction, there may be a certain degree of pus, the appearance of follicle consistency of small pustules. In addition, there is also the possibility of eczema, which is a localized skin reaction caused by localized allergies or the ingestion of allergenic foods.