RESUMO
For the epidemiological monitoring and clinical case management of leishmaniasis, determination of the causative Leishmania species gains importance. Current assays for the Old World often suffer from drawbacks in terms of validation on a geographically representative sample set and the ability to recognize all species complexes. We want to contribute to standardized species typing for Old World leishmaniasis. We determined the ribosomal DNA internal transcribed spacer 1 sequence of 24 strains or isolates, and validated four species-specific polymerase chain reactions (PCRs) amplifying this target. They discriminate L. aethiopica, L. tropica, L. major, and the L. donovani complex, use the same cycling conditions, and include an internal amplification control. Our PCRs amplify 0.1 pg of Leishmania DNA, while being 100% specific for species identification on an extensive panel of geographically representative strains and isolates. Similar results were obtained in an endemic reference laboratory in Kenya. Species could also be identified in clinical specimens. The presented PCRs require only agarose gel detection, and have several other advantages over many existing assays. We outline potential problems, suggest concrete solutions for transferring the technique to other settings, and deliver the proof-of-principle for analyzing clinical samples.
Assuntos
Leishmania/classificação , Leishmania/isolamento & purificação , Leishmaniose/diagnóstico , Parasitologia/métodos , Reação em Cadeia da Polimerase/métodos , Animais , Primers do DNA/genética , DNA de Protozoário/genética , DNA Espaçador Ribossômico/genética , Cães , Eletroforese em Gel de Ágar , Humanos , Leishmania/genética , Leishmaniose/parasitologia , Sensibilidade e EspecificidadeRESUMO
A nine year aged male presented with facial lesions and the problem of responding to conventional treatment of leishmaniasis. Multiple injections of antimony and several topical ointments had been administered in hospital but fresh lesions erupted with potential to disfigure. Smears examined from nodular lesions confirmed presence of Leishmania amastigotes and parenteral pentostam was commenced for over eight weeks. A partial clinical outcome was achieved judged by extent of re-epithelialisation. Combined therapy of pentostam and oral allopurinol at a dose of 7mg/kg/day was started and finalised at 120 days. All facial lesions receded and 100% re-epithelialisation of the lesions established.