Must See the Biggest Ever Blackhead

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• published: 24 Aug 2016
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"Blackhead" redirects here. For other uses, see Blackhead (disambiguation). Blackhead plural comedones[1] Blausen 0811 SkinPores.png Illustration of blackhead Classification and external resources Specialty Dermatology ICD-9-CM 706.1 [edit on Wikidata] A comedo is a clogged hair follicle (pore) in the skin.[2] Keratin (skin debris) combines with oil to block the follicle.[3] A comedo can be open (blackhead) or closed by skin (whitehead), and occur with or without acne.[3] The word comedo comes from the Latin comedere, meaning "to eat up," and was historically used to describe parasitic worms; in modern medical terminology, it is used to suggest the worm-like appearance of the expressed material.[1] The chronic inflammatory condition that usually includes both comedones and inflamed papules and pustules (pimples) is called acne.[3][4] Infection causes inflammation and the development of pus.[2] Whether or not a skin condition classifies as acne depends on the amount of comedones and infection.[4] Comedones should not be confused with sebaceous filaments. Comedo-type ductal carcinoma in situ (DCIS) is not related to the skin conditions discussed here. DCIS is a non-invasive form of breast cancer, but comedo-type DCIS may be more aggressive and so may be more likely to become invasive.[5] Contents [hide] 1 Causes 2 Pathophysiology 3 Management 4 Rare conditions 5 References Causes[edit] Oil production in the sebaceous glands increases during puberty, causing comedones and acne to be common in teenagers.[3][4] Acne is also found pre-menstrually and in women with polycystic ovarian syndrome.[3] Smoking may worsen acne.[3] Oxidation rather than poor hygiene or dirt causes blackheads to be black.[2] Washing or scrubbing the skin too much could make it worse, by irritating the skin.[2] Touching and picking at comedones might cause irritation and spread infection.[2] It is not clear what effect shaving has on the development of comedones or acne.[2] Some, but not all, skin products might increase comedones by blocking pores,[2] and greasy hair products (like pomades) can worsen acne.[3] Skin products that claim to not clog pores may be labeled noncomedogenic or non-acnegenic.[6] Make-up and skin products that are oil-free and water-based may be less likely to cause acne.[6] It is not known whether dietary factors or sun exposure make comedones better, worse or have no effect.[3] A hair that does not emerge normally can also block the pore and cause a bulge or lead to infection (causing inflammation and pus).[4] Genes may play a role in the chances of developing acne.[3] Comedones may be more common in some ethnic groups.[3][7] Africans and African-Americans may experience more inflammation in comedones, more comedonal acne, and earlier onset of inflammation.[3][7] Pathophysiology[edit] Comedones are associated with the pilosebaceous unit, which includes a hair follicle and sebaceous gland. These units are mostly on the face, neck, upper chest, shoulders and back.[3] Excess keratin combined with sebum can plug the opening of the follicle.[3][8] This small plug is called a microcomedo.[8] Androgens increase sebum (oil) production.[3] If sebum continues to build up behind the plug, it can enlarge and form a visible comedo.[8] A comedo may be open to the air ("blackhead") or closed by skin ("whitehead").[2] Being open to the air causes oxidization, which turns it black.[2] Propionibacterium acnes is the suspected infectious agent in acne.[3] It can proliferate in sebum and cause inflamed pustules (pimples) characteristic of acne.[3] Nodules are inflamed, painful deep bumps under the skin.[3] Comedones that are 1 mm or larger are called macrocomedones.[9] They are closed comedones and are more frequent on the face than neck.[10] Solar comedones (sometimes called senile comedones) are related to many years of exposure to the sun, usually on the cheeks, not to acne-related pathophysiology