cystic acne, the most severe type of inflammatory acne on white background.

cystic acne cyst pimple pus severe nodulocystic nodule nodular skin face inflamed swelling inflammatory inflammation clogged pore bump red diagram scar formation painful large propionibacterium acnes sebum sebaceous gland follicle dead cell epidermis layer surface anatomy bacteria beauty body dermatology facial care infection vector problem treatment aesthetic compare flat design infographic damage