Pityriasis alba

Pityriasis alba Pitiriasis white is a nonspecific dermatitis of unknown etiology that causes scaly erythematous patches. They address areas of hypopigmentation and leave. Lesions commonly occur on the face, especially cheeks. The lesions may be erythematous or pruritic hypopigmented macules evolves, squamous. Patients reports predominant lesions summer, after hiperpigmentarii surrounding area associated with sun exposure. Mortality is not associated with this condition. It is an asymptomatic self-limited disease that resolves without medical intervention. One problem may be cosmetic appearance.
The cause is unknown. Dermatological consultation is not necessary in mild cases but becomes necessary in the extensive. Because the condition is self-limiting is not required treatment. Pityriasis alba has no medical consequences and side effects of medication outweigh the cosmetic effects of the interventions. Most commonly used remedies are emolientele, topical steroids, phototherapy with psoralen and ultraviolet A, with limited effectiveness. Depigmentation is permanent. Pityriasis alba is usually self-limiting and lesions resolve in adulthood. Duration of symptoms is different for each patient.
Pathogenesis and causes
There has been no known cause for pityriasis alba. Atopy and postinflammatory changes are current theories on the origin of the lesions. Pitiriacitrinului secondary hypopigmentation is considered a substance produced by Malassezia that acts as a natural sun shield. Biopsy and histology shows hyperkeratosis, parakeratoza, acanthosis, perivascular infiltrates and sponginess. Sebaceous gland atrophy is noted in over half of cases. Degenerative changes of melanocytes and keratinocytes melanosomilor reduction is also noted. The fault is considered to be due to diminution of melanin.
Signs and symptoms
Pityriasis alba is mainly seen in people under 20 years. Lesions appear on the face, especially cheeks. Or pruritic erythematous lesions may be the beginning, evolving from squamous macules, hypopigmented. Patients may experience this summer when the skin lesions especially around is tanned and they are more evident.
There are three stages of the disease: Erythematous, papular lesions Hypochromic-papular lesions Smooth-hypochromic lesions. Initial erythema may be obvious to some lesions crusting, erythema is still easy because many patients do not realize this point. New lesions may develop at different time. Duration of lesions ranged from one month to 10 years. The average duration of common facial shape is 1 year.
Physical examination. Pityriasis alba is characterized by round-oval spots, hypopigmented, scaly face, arms, neck or shoulders. Trunk and legs are less affected. Lesions vary diemnsiune 1-4 cm. patients usually have multiple lesions ranging from 4 to 20 in number. Scales are fine and adherent. The most common lesions affecting the face. In children they are limited to the face. The areas around the mouth, cheeks and chin are the most common. Less face is avoided and the lesions appear on the trunk and lower member. Rare patients with extensive disease can be extensive pityriasis shows numerous lesions on the trunk and extremities. This form occurs in elderly patients.
Diagnosis
Laboratory studies: -Correct diagnosis is suggested by the patient's age, scy = uamele Finally, hypopigmentation and distribution of lesions Potassium hydroxide-examination is performed to rule out tinea versicolor, tinea corporis or tinea facie.
Histological examination. Skin biopsy is not necessary. Studies show reduction in the number of active melanocytes and reducing the number and size of melanosomes in the affected skin. The differential diagnosis is made with the following conditions: atopic dermatitis, contact dermatitis, pityriasis pink, tinea versicolor, progressive macular hipomelanoza, psoriasis, eczema numulara, depigmented nevus' micosis hypopigmented fungoides, vitiligo.
Treatment
Treatment consists primarily of proper skin care and educating parents and patients on self-limiting and benign nature of the disease. You can use an emollient cream or mild hydrocortisone to decrease redness and itching if present. Immunomodulators such as tacrolimus can be used to treat pityriasis alba and is safe for young children. Extensive disease can be treated with psoralen and ultraviolet A fotochimioterapia, though it carries risks and is not indicated. It indicates the use of sunscreen, and can help alleviate the obvious injuries. The risk of sunburn is slightly increased for these lesions. Pityriasis alba is self-limited and patients are asymptomatic. Cosmetic appearance may be a problem. The prognosis is good with total repigmentation. There are no long term side effects.