Imuno-histoquímica para o diagnóstico precoce de vitiligo
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Data
2008-10-01
Autores
Nai, Gisele Alborghetti [UNESP]
Miot, Luciane Bartoli Donida [UNESP]
Miot, Hélio Amante [UNESP]
Marques, Mariângela Esther Alencar [UNESP]
Título da Revista
ISSN da Revista
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Editor
Sociedade Brasileira de Patologia ClínicaSociedade Brasileira de PatologiaSociedade Brasileira de Citopatologia
Resumo
O vitiligo é uma doença de pele freqüente que acomete 1% da população e é caracterizada por máculas despigmentadas conseqüentes à perda progressiva e localizada dos melanócitos da epiderme. Na maioria dos pacientes, o diagnóstico é feito por exame clínico. A biópsia da pele é realizada quando há necessidade de diagnóstico diferencial com doenças hipocromiantes. O diagnóstico histopatológico de vitiligo é difícil nos preparados corados por hematoxilina e eosina (HE). Há poucos estudos sobre a melhoria da qualidade diagnóstica no vitiligo. OBJETIVO: Avaliar a utilidade dos marcadores imuno-histoquímicos proteína S-100, human melanoma black-45 (HMB-45) e Melan-A para o diagnóstico precoce em casos clinicamente suspeitos ou duvidosos de vitiligo. Material e métodos: Lâminas histológicas de biópsias de pele sã e lesada de 10 pacientes com suspeita clínica de vitiligo coradas pelos métodos de HE, proteína S-100, HMB-45 e Melan-A. Utilizou-se contracoloração com Giemsa como modificação técnica para diferenciar a melanina da imunomarcação. RESULTADOS: Seis casos, com manifestação clínica recente, apresentaram infiltrado linfocitário, do tipo dermatite de interface, na pele lesada na HE. As colorações por S-100, HMB-45 e Melan-A marcaram os melanócitos da camada basal da pele sã, e a proteína S-100 evidenciou as células de Langerhans. Na pele lesada, os melanócitos estavam ausentes ou diminuídos quando comparados com a pele normal. A proteína S-100 demonstrou maior número de células de Langerhans, o que é característico das lesões de vitiligo. CONCLUSÃO: A imuno-histoquímica pode ser utilizada como método auxiliar no diagnóstico dos casos duvidosos de vitiligo.
Vitiligo is a frequent skin disease that affects 1% of the population. It presents depigmented macules resulting from a gradual loss of melanocytes in the epidermis. In most cases, the diagnosis is made by clinical examination. Skin biopsies are performed when it is necessary to compare it with other hypomelanosis. Histopathological diagnosis of vitiligo is often difficult in hematoxylin-eosin (H&E) stained sections. There are a few studies on the improvement of diagnostic quality in vitiligo. OBJECTIVE: To evaluate the use of immunohistochemical markers, such as S-100 protein, human melanoma black-45 (HMB-45) and Melan-A, in the early diagnosis of clinically suspected or doubtful cases of vitiligo. Materials and methods: Histological sections of biopsies from healthy and affected skin areas from 10 patients clinically suspected of vitiligo. The samples were stained with H&E, S-100 protein, HMB-45 and Melan-A methods. Counterstaining with Giemsa was applied as a technical modification to differentiate melanin from immunolabelling. RESULTS: Six cases with recent clinical manifestation showed lymphocyte infiltrates, such as interface dermatitis, in the affected skin in the H&E staining technique. S-100 protein, HMB-45 and Melan-A staining marked the basal layer melanocytes of the healthy skin and S-100 protein antigen evidenced Langerhans cells. Melanocytes were absent or less frequent in affected skin areas in comparison with normal skin. S-100 protein showed a larger number of Langerhans cells, what is a common feature of vitiligo lesions. Conclusion: Immunohistochemistry may be used as an auxiliary technique for the diagnosis of suspected vitiligo cases.
Vitiligo is a frequent skin disease that affects 1% of the population. It presents depigmented macules resulting from a gradual loss of melanocytes in the epidermis. In most cases, the diagnosis is made by clinical examination. Skin biopsies are performed when it is necessary to compare it with other hypomelanosis. Histopathological diagnosis of vitiligo is often difficult in hematoxylin-eosin (H&E) stained sections. There are a few studies on the improvement of diagnostic quality in vitiligo. OBJECTIVE: To evaluate the use of immunohistochemical markers, such as S-100 protein, human melanoma black-45 (HMB-45) and Melan-A, in the early diagnosis of clinically suspected or doubtful cases of vitiligo. Materials and methods: Histological sections of biopsies from healthy and affected skin areas from 10 patients clinically suspected of vitiligo. The samples were stained with H&E, S-100 protein, HMB-45 and Melan-A methods. Counterstaining with Giemsa was applied as a technical modification to differentiate melanin from immunolabelling. RESULTS: Six cases with recent clinical manifestation showed lymphocyte infiltrates, such as interface dermatitis, in the affected skin in the H&E staining technique. S-100 protein, HMB-45 and Melan-A staining marked the basal layer melanocytes of the healthy skin and S-100 protein antigen evidenced Langerhans cells. Melanocytes were absent or less frequent in affected skin areas in comparison with normal skin. S-100 protein showed a larger number of Langerhans cells, what is a common feature of vitiligo lesions. Conclusion: Immunohistochemistry may be used as an auxiliary technique for the diagnosis of suspected vitiligo cases.
Descrição
Palavras-chave
Vitiligo, Hipomelanose cutânea, Imuno-histoquímica, Diagnóstico, Melan-A, Vitiligo, Cutaneous hypomelanosis, Immunohistochemistry, Diagnosis, Melan-A
Como citar
Jornal Brasileiro de Patologia e Medicina Laboratorial. Sociedade Brasileira de Patologia ClínicaSociedade Brasileira de PatologiaSociedade Brasileira de Citopatologia, v. 44, n. 5, p. 367-373, 2008.