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Differential diagnosis of pigmented nail lesions
Laura Bertanha1, Leandro Fonseca Noriega2, Nilton Gióia Di Chiacchio3
1Dermatology Service, Hospital do Servidor Público Municipal de São Paulo, São Paulo, SP, Brazil; Dermatology Service, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, SP, Brazil.
Abstract:
The diagnosis of pigmented nail lesions is a concern for both general practitioners and dermatologists, due to the possibility of indicating nail melanoma. The origin of the dark pigmentation can be either melanocytic or non-melanocytic (fungi, bacteria, or blood), and clinical evaluation alone may not be sufficient for differentiation, requiring additional exams. Onychoscopy provides valuable information prior to biopsy. The causes of nail pigmentation will be described to aid in the differential diagnosis.
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