* The diagnosis is clinical; histological examination is rarely necessary (atypical or complicated shapes)
* Sign of bloody dew after scraping with a curette (a sign of Auspitz)
* Psoriasis predominantly affects extensor surfaces of the limbs (elbows, knees), the lumbosacral area and scalp. On members lesions are usually symmetrical.
* Pruritus was observed in ⅓ of cases.
* Nummular Psoriasis: midsize psoriasis lesions
* At the scalp lesions resembling pityriasis capitis simple but erythematous base straightens diagnosis. Usually the scalp psoriasis does not cause residual alopecia.
* The face is rarely achieved in isolation
* Achievement of folds is a chronic intertrigo (inverse psoriasis); erythematous lesion no or little flaky.
* The achievement of the nail (⅓ of cases) pitting; peri-Nail involvement is often associated (paronychia erythematous scaly)
* Achievement of mucous: On language: it can be a fissured tongue, or geographical. Exfoliative glossitis.Achievement possible penis …
* Psoriasis on old scar is frequently (Koebner phenomenon)
* The child is often psoriasis psoriasis gout, acute onset which followed willingly angina. The involvement of the face is common.
* Psoriasis during HIV infection presents more severe and extended forms.
Histology:
– Parakeratotic hyperkeratosis (stratum corneum ++)
– Disappearance of the granular layer
– ++ Thickness of the epidermis (acanthosis) with elongation of dermal papillae (papillomatosis).
– PNN grouped in small clusters in the surface layers of the epidermis (pseudo-abscesses of Munro-Sabouraud)
* Seborrheic dermatitis is a problem especially in diagnostic maps of the scalp or face. Psoriasiform secondary syphilitic (copper character ring appearance dander, infiltration wheal)
* Systemic corticosteroids may cause a severe or complicated further, especially at weaning
* Other drugs that can aggravate (or trigger) psoriasis: lithium, beta blockers, chloroquine, interferon-α.
* Other triggering factors: psychological trauma; skin trauma; bacterial infections (streptococcal infections in children)
* The prognosis can be set into play in cases of generalized pustular psoriasis or in case of psoriatic erythroderma (edematous form).
* Psoriatic arthritis: 20% of psoriasis; the progression of joint flare is independent of skin breakouts. The axial psoriatic arthritis is rare (as peripheral arthritis).
* Extra Psoriasis is an excellent indication of phototherapy. In adults PUVA is offered as first line; in children and pregnant women is UVB phototherapy.