Assuntos
Dermatite/imunologia , Dermatite/patologia , Urticária/imunologia , Urticária/patologia , Antígenos CD/imunologia , Biópsia/métodos , Antígenos CD8/imunologia , Estudos Transversais , Dermatite/diagnóstico , Eczema/diagnóstico , Eczema/imunologia , Eczema/patologia , Fatores de Transcrição Forkhead/metabolismo , Humanos , Imunofenotipagem , Cadeias alfa de Integrinas/imunologia , Estudos Retrospectivos , Linfócitos T Reguladores/imunologia , Urticária/diagnósticoRESUMO
Both reticulohistiocytoma and multicentric reticulohistiocytosis are defined by their shared histopathologic appearance of dermal proliferations of mononuclear histiocytes and multinucleated giant cells with eosinophilic "ground-glass" or "two-toned" cytoplasm. To assess the specificity of the histopathologic findings seen in reticulohistiocytoma and reticulohistiocytosis, this study retrospectively examined 109 random, unscreened excision specimens of ruptured cysts to determine at what frequency "ground-glass" or "two-toned" histiocytes and multinucleated giant cells are seen in reactive cutaneous infiltrates. Slightly more than half (56.9%) of the ruptured cyst cases had "ground-glass" histiocytes. The majority (84%) of the ruptured cyst cases had multinucleated giant cells. The shared histologic findings associated with reticulohistiocytoma and reticulohistiocytosis are much more pervasive than previously documented and are relatively non-specific. Identification of immunohistochemical and/or molecular biomarkers that distinguish reticulohistiocytoma and reticulohistiocytosis from histologic mimickers would likely prove indispensable.
Assuntos
Células Gigantes/patologia , Histiócitos/patologia , Histiocitose de Células não Langerhans/patologia , Técnicas Histológicas/métodos , Dermatopatias/diagnóstico , Biópsia/métodos , Diagnóstico Diferencial , Humanos , Imuno-Histoquímica/métodos , Sensibilidade e EspecificidadeRESUMO
Pityriasis lichenoides-like drug reactions simulate pityriasis lichenoides clinically and histopathologically, though important differences exist. As a rule, pityriasis lichenoides has minimal to no eosinophils. However, this case illustrates that pityriasis lichenoides-like drug reaction can present with numerous eosinophils. This, in our experience is not rare, but contrasts with clinical reports in the literature that describe pityriasis lichenoides-like drug reactions with minimal to no eosinophils in the infiltrate. While similar, distinguishing these diseases is important given that pityriasis lichenoides is a lymphoproliferative disorder with a more protracted clinical course that is difficult to treat. We provide histopathological clues to aid in this important distinction.