Carneiro Francisca Regina Oliveira, Amaral Gabriela Borborema do, Mendes Maiana Darwich, Quaresma Juarez Antônio Simões
Universidade do Estado do Pará, Belém, PA, Brazil.
An Bras Dermatol. 2014 Mar-Apr;89(2):245-8. doi: 10.1590/abd1806-4841.20142201.
Pityriasis alba affects 1% of the world population and about 9.9% of the children in Brazil. However, its etiology remains uncertain.
The objective of the present study was to evaluate the immunoexpression of factor XIIIa in dermal dendrocytes of skin lesions of pityriasis alba.
Twenty patients with pityriasis alba and 20 patients with atopic dermatitis underwent biopsy. The dermal dendrocytes marked by factor XIIIa were counted by means of immunohistochemical analysis.
The mean amount of dermal dendrocytes found in the patients with pityriasis alba was 2, whereas in the patients with atopic dermatitis it was 4, with a statistically significant difference between them. A cutoff point of 3 cells/square inch was established to differentiate pityriasis alba from atopic dermatitis, with 80% sensibility and 90% specificity.
We believe that pityriasis alba and atopic dermatitis should be considered different clinical forms within the spectrum of atopic disease, in which sun radiation plays an important role by modulating the progression of the disease.
白色糠疹影响全球1%的人口,在巴西约9.9%的儿童受其影响。然而,其病因仍不明确。
本研究的目的是评估白色糠疹皮肤病变中真皮树突状细胞中因子XIIIa的免疫表达。
对20例白色糠疹患者和20例特应性皮炎患者进行活检。通过免疫组织化学分析对因子XIIIa标记的真皮树突状细胞进行计数。
白色糠疹患者真皮树突状细胞的平均数量为2个,而特应性皮炎患者为4个,两者之间存在统计学显著差异。确定以每平方英寸3个细胞为区分白色糠疹和特应性皮炎的临界点,敏感性为80%,特异性为90%。
我们认为白色糠疹和特应性皮炎应被视为特应性疾病谱中的不同临床形式,其中太阳辐射通过调节疾病进展发挥重要作用。