RESUMO
Through whole-genome sequencing analysis, we identified non-Leishmania parasites isolated from a man with a fatal visceral leishmaniasis-like illness in Brazil. The parasites infected mice and reproduced the patient's clinical manifestations. Molecular epidemiologic studies are needed to ascertain whether a new infectious disease is emerging that can be confused with leishmaniasis.
Assuntos
Infecções por Euglenozoa/epidemiologia , Infecções por Euglenozoa/parasitologia , Trypanosomatina/genética , Idoso , Animais , Brasil/epidemiologia , DNA Espaçador Ribossômico , Genes de Helmintos , Humanos , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/parasitologia , Masculino , Camundongos , Filogenia , Trypanosomatina/classificaçãoRESUMO
BACKGROUND: Leishmania (Leishmania) amazonensis infection in man results in a clinical spectrum of disease manifestations ranging from cutaneous to mucosal or visceral involvement. In the present study, we have investigated the genetic variability of 18 L. amazonensis strains isolated in northeastern Brazil from patients with different clinical manifestations of leishmaniasis. Parasite DNA was analyzed by sequencing of the ITS flanking the 5.8 S subunit of the ribosomal RNA genes, by RAPD and SSR-PCR and by PFGE followed by hybridization with gene-specific probes. RESULTS: ITS sequencing and PCR-based methods revealed genetic heterogeneity among the L. amazonensis isolates examined and molecular karyotyping also showed variation in the chromosome size of different isolates. Unrooted genetic trees separated strains into different groups. CONCLUSION: These results indicate that L. amazonensis strains isolated from leishmaniasis patients from northeastern Brazil are genetically diverse, however, no correlation between genetic polymorphism and phenotype were found.