What's with the red back?

1, back long red knot, knot has white tip, consider folliculitis, is due to eat too much spicy greasy food, high androgen level in the body, hair follicle hole blockage, and formed. With clindamycin gel rubbed affected area, oral tetracycline antibiotics treatment, diet to light mainly, prevent eating spicy, greasy food. 2. The newly bought clothes were not cleaned. After wearing them, the back and other parts of the body showed red bumps the size of rice grains, accompanied by itching. It was considered to be caused by allergy. Oral anti-allergy drugs were taken. Calamine lotion was applied to the affected parts. 3. Red bumps grew on the back. The bumps gradually expanded to form red spots covered with white scales. After deducting the scales, there were punctate bleeding spots. Psoriasis was considered. Tacrolimus cream was applied to the affected parts and Xiaoyin granules were taken orally for treatment.