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Several similarities exist between psoriasis and dandruff, non-contagious skin conditions characterized by inflammation, flaking, and itching. Although these diseases often mimic one another in that they both appear on the scalp and can exacerbate under the same conditions, causation is different. One disease, psoriasis, occurs due to immunity issues and dandruff happens because of excess oil production on the skin and may be contributed to a microbial agent. Doctors distinguish between the conditions usually by observation of the rash, taking particular notice of where inflammations occur. The course and pattern of psoriasis involves several different types, while dandruff can vary from a mild effect to increased signs.
A major difference between psoriasis and dandruff is that psoriasis is a disorder affecting immune function. Specialists think that the disease is autoimmune, meaning that, in an effort to protect itself, the body assaults its own tissues as it would a foreign invader such as a virus. Often occurring with other critical diseases, psoriasis is actually caused by an overproduction of skin cells of the epidermis which has been determined to be a result of an issue with the hyperactive behavior of t-lymphocytes. The reason for dandruff is thought to be associated with a mix of increased sebum production and decreased t-lymphocyte function, as well as malassezia, which is a type of fungus.
Psoriasis and dandruff differ in the typical places that rashes appear and their appearance. With psoriasis, the common locations for scaling are the knees, elbows, and scalp, while the primary area that people have dandruff is on the scalp only, although certain people do get this on their faces and in facial hair. The white-silver scales which tend to be thicker set psoriasis apart from dandruff and is easily seen due to its tendency to extend beyond the surface of the scalp, continuing on the brow and neck. Referred to as seborrheic dermatitis, dandruff is only typically noticeable if the scales fall onto clothing, or if the hair is parted.
Both psoriasis and dandruff differ in their courses. As of 2011, several varieties of psoriasis have been identified and each type determines its appearance and the body region that it affects, as well as other diseases which frequently co-occur with this condition. For example, psoriasis of the inverse type tends to manifest within skin folds like the buttocks and underneath the arms. Of all of these, plaque psoriasis is the most typical among people with psoriasis as of 2011. Although both conditions may come and go throughout life, there is one condition of dandruff and it varies in degree of severity from individual to individual.