We report a female newborn with a dystrophic epidermolysis bullosa. The diagnosis was made by electron microscopy of a bullous skin lesion. The importance of reaching a specific diagnosis is underscored. Close relatives can therefore be informed and educated about prognosis, etiology and the possibility of having new affected offspring. An accurate diagnosis can be reached through electronic microscopy or modern immunohistochemical techniques. Further complementary information given by conventional histology is required. A complete study is recommended to minimize errors in the intepretation of morphology (Rev Méd Chile 2004; 132: 614-8).