Experimental models of Schistosoma mansoni infections in mammals have contributed greatly in understanding the pathology and pathogenesis of human infection. The absence of earlier reviews regarding specific strains of the Amazon region prompted research, which the main objective was to describe histopathological lesions in different phases of schistosomiasis in a murine model using PC (Pará) and LILA (Maranhão) S. mansoni strains. One hundred and eighty young female albino swiss mice (Mus musculus) were used and were randomly divided into five groups and controls), according to the number of cercariae injected and the strain adopted. Animals were sacrificed in predetermined periods (35, 56, 112, 156, and 180 days) in an attempt to follow the evolution of the disease in the histological sections of their tissues at different phases of infection. Our findings were compatible with the data already described by others authors using different strains of S. mansoni, making it possible to identify some peculiarities, which are discussed in this work. In conclusion, the strains of parasite used did not modify the histopathological findings in the tissues of infected mice in any significant way when compared with the results of other studies using different strains.

Biopsies are occasionally necessary to confirm the diagnosis of secondary-stage syphilis, currently achieved by clinico-serological correlation. However, histopathologic examination may offer clues that can lead to the diagnosis of the disease in previously unsuspected or unusual cases. We report the case of a 35-year-old male patient with vitiligo-like lesions for two years, whose diagnosis of syphilis was suggested only after histopathologic examination. Some microscopic aspects observed are discussed and compared to data from the literature. Keywords: Dermatitis; Histology; Syphilis, cutaneous; Treponemal infections Resumo: Biópsias são ocasionalmente necessárias para confirmação diagnóstica de sífilis secundária, normalmente obtida por correlação clínico-sorológica. Entretanto, o exame histopatológico pode oferecer pistas que conduzam a um diagnóstico em casos antes insuspeitos ou de apresentação clínica incomum. Apresentamos um paciente de 35 anos, há dois com lesões acrômicas vitiligoides, para o qual sífilis foi sugerida somente após o exame histopatológico. Alguns aspectos microscópicos observados são discutidos e comparados com dados disponíveis na literatura.