Thesis (M.Sc. (Anatomy)) -- Mahidol University, 1969.

Introdução: As alopecias cicatriciais são subdivididas em primárias e secundárias. Nas alopecias cicatriciais primárias o folículo piloso é o alvo principal da destruição; diferentemente das secundárias onde a destruição folicular não é o evento patológico primário. Objetivo: Revisar os achados histológicos de pacientes com diagnóstico de alopecia cicatricial primária, em uma fase tardia e reclassificá-los em seus respectivos subtipos. Casuística e Métodos: Os espécimes de biópsia de pacientes com diagnóstico histológico prévio de alopecia cicatricial foram revisados e submetidos a colorações por hematoxilina e eosina (HE), ácido periódico-Schiff (PAS) e Weigert, a fim de reclassificá-los de acordo com os diferentes subtipos de alopecia. Foram utilizados para a revisão histológica critérios de infiltrado inflamatório acrescidos de coloração para fibra elástica. Resultados: Os 37 casos de alopecia cicatricial primária foram reclassificados em: lupus eritematoso discóide (16), líquen plano pilar (4), pseudopelada de Brocq (12), foliculite decalvante (3), foliculite abscedante/dessecante (1), e alopecia não-específica (1). Conclusão: Mesmo em uma fase tardia, pauci ou não inflamatória, o exame histológico, utilizando colorações de rotina, PAS e coloração para fibra elástica, permitiu o diagnóstico mais acurado das alopecias cicatriciais primárias / BACKGROUND: Scarring alopecias are classified into primary and secondary according to the initial site of inflammation. In primary scarring alopecias, the hair follicle is the main target of destruction. The term secondary cicatricial alopecia implies that follicular destruction is not the primary pathologic event. AIMS: To review the histopathologic diagnoses of cases of cicatricial alopecia in order to classify them according to the North American Hair Research Society. PATIENTS AND METHODS: Patients with biopsy specimens diagnosed as cicatricial alopecia seen from 2000 to 2005 at the Dermatologic Department of Hospital das Clínicas, São Paulo University Medical School had hematoxylin and eosin, Periodic Acid-Schiff (PAS) and Weigert stained slides reevaluated and sub-typed into different primary cicatricial alopecias. RESULTS: Thirty-seven cases of primary cicatricial alopecias were reclassified as: discoid lupus erythematosus (16), lichen planus pilaris (4), pseudopelade of Brocq (12), folliculitis decalvans (3), dissecting folliculitis (1), and non-specific scarring alopecia (1). CONCLUSIONS: Even in late, pauci or noninflammatory phases, an approach with systematic evaluation of a constellation of criteria in routine hematoxylin and eosin stain, PAS and Weigert stain permitted an accurate diagnosis of cicatricial alopecias

Introdução: As alopecias cicatriciais são subdivididas em primárias e secundárias. Nas alopecias cicatriciais primárias o folículo piloso é o alvo principal da destruição; diferentemente das secundárias onde a destruição folicular não é o evento patológico primário. Objetivo: Revisar os achados histológicos de pacientes com diagnóstico de alopecia cicatricial primária, em uma fase tardia e reclassificá-los em seus respectivos subtipos. Casuística e Métodos: Os espécimes de biópsia de pacientes com diagnóstico histológico prévio de alopecia cicatricial foram revisados e submetidos a colorações por hematoxilina e eosina (HE), ácido periódico-Schiff (PAS) e Weigert, a fim de reclassificá-los de acordo com os diferentes subtipos de alopecia. Foram utilizados para a revisão histológica critérios de infiltrado inflamatório acrescidos de coloração para fibra elástica. Resultados: Os 37 casos de alopecia cicatricial primária foram reclassificados em: lupus eritematoso discóide (16), líquen plano pilar (4), pseudopelada de Brocq (12), foliculite decalvante (3), foliculite abscedante/dessecante (1), e alopecia não-específica (1). Conclusão: Mesmo em uma fase tardia, pauci ou não inflamatória, o exame histológico, utilizando colorações de rotina, PAS e coloração para fibra elástica, permitiu o diagnóstico mais acurado das alopecias cicatriciais primárias / BACKGROUND: Scarring alopecias are classified into primary and secondary according to the initial site of inflammation. In primary scarring alopecias, the hair follicle is the main target of destruction. The term secondary cicatricial alopecia implies that follicular destruction is not the primary pathologic event. AIMS: To review the histopathologic diagnoses of cases of cicatricial alopecia in order to classify them according to the North American Hair Research Society. PATIENTS AND METHODS: Patients with biopsy specimens diagnosed as cicatricial alopecia seen from 2000 to 2005 at the Dermatologic Department of Hospital das Clínicas, São Paulo University Medical School had hematoxylin and eosin, Periodic Acid-Schiff (PAS) and Weigert stained slides reevaluated and sub-typed into different primary cicatricial alopecias. RESULTS: Thirty-seven cases of primary cicatricial alopecias were reclassified as: discoid lupus erythematosus (16), lichen planus pilaris (4), pseudopelade of Brocq (12), folliculitis decalvans (3), dissecting folliculitis (1), and non-specific scarring alopecia (1). CONCLUSIONS: Even in late, pauci or noninflammatory phases, an approach with systematic evaluation of a constellation of criteria in routine hematoxylin and eosin stain, PAS and Weigert stain permitted an accurate diagnosis of cicatricial alopecias

Primary scalp alopecia is classically divided into cicatricial (scarring) and non-cicatricial (non-scarring). Challenging cases are assessed with a scalp biopsy. The use of both horizontal and vertical sections (HoVert sections) has dramatically improved the accuracy of histopathological diagnosis. In this work, we have used immunostaining to address diagnostic difficulties, which persist despite all currently available tools. We performed an immunostain panel (CD3, CD4, CD8 and CD20) in order to distinguish pattern hair loss from alopecia aerate in cases which do not have the usual peribulbar lymphocytic infiltrate and showed that CD3+ T-lymphocytes within the empty fibrous follicular tracts favor a diagnosis of alopecia areata. We performed CD123 in order to distinguish lichen planopilaris from alopecia lupus erythematosus in cases with only a superficial lymphocytic infiltrate and an uninvolved interfollicular epidermis and showed that clusters of CD123+ plasmacytoid dendritic cells favor a diagnosis of lupus erythematosus. We performed cytokeratin 15 in order to assess whether the loss of the follicular bulge stem cells has diagnostic value in cicatricial alopecia and demonstrated that the loss of cytokeratin 15+ bulge stem cells is identified in lichen planopilaris, frontal fibrosing alopecia, and lupus erythematous, so cytokeratin 15 has no diagnostic value. We have attempted to integrate the new concepts and our findings into the traditional classifications of alopecia and proposed a new diagnostic algorithm. In conclusion, immunostaining combined with HoVert grossing advances the accuracy of histopathological diagnosis of primary scalp alopecia. / L’alopécie primitive du cuir chevelu est habituellement classée en cicatricielle et non-cicatricielle. Dans les cas difficiles, la biopsie du cuir chevelu peut aider au diagnostic. L’utilisation de coupes, à la fois verticales et horizontales sur le même spécimen (technique HoVert), a radicalement amélioré le diagnostic histopathologique. Dans ce travail, nous avons utilisé l’immunohistochimie pour évaluer les difficultés diagnostiques qui persistent malgré tous les outils actuels. Nous avons utilisé les CD3, CD4, CD8 et CD20 pour différencier l’alopécie androgénique de la pelade dépourvue de l’infiltrat lymphocytaire péribulbaire habituel et nous avons démontré que la présence de lymphocytes CD3+ dans les travées folliculaires fibreuses est en faveur de la pelade. Nous avons utilisé le CD123 pour différencier le lichen plan pilaire du lupus érythémateux alopécie avec infiltrat lymphocytaire superficiel et sans atteinte de l’épiderme interfolliculaire et nous avons démontré que la présence d’amas de cellules dendritiques plasmacytoïdes CD123+ est en faveur du lupus érythémateux. Nous avons utilisé la cytokératine 15 pour évaluer si la perte des cellules souches du bulge a une valeur diagnostique dans l’alopécie cicatricielle et nous avons démontré que cette perte s’observait de manière identique dans le lichen plan pilaire, l’alopécie frontale fibrosante comme dans le lupus érythémateux et n’avait donc aucune valeur diagnostique. Nous avons tenté d’intégrer les nouveaux concepts et nos données dans les classifications traditionnelles des alopécies et nous avons élaboré un nouvel algorithme diagnostique. L’association des immunomarquages avec la technique HoVert ouvre de nouvelles perspectives dans le diagnostic histopathologique des alopécies primaires du cuir chevelu. / Doctorat en Sciences médicales (Médecine) / info:eu-repo/semantics/nonPublished