RESUMO
Since it is known that Entamoeba dispar is non-pathogenic and morphologically similar to E. histolytica, there are many targets used in PCR for differentiating these species. However, obtaining high quality DNA from fecal samples is fundamental for PCR. Most methods are laborious or use kits that make diagnosis expensive. In the present work, a new simple, fast and cheap technique of DNA extraction from fecal samples was combined with a PCR for an episomal target in order to identify E. histolytica and E. dispar in feces.
Assuntos
DNA de Protozoário/isolamento & purificação , Entamoeba histolytica/classificação , Entamoeba/classificação , Entamebíase , Fezes/parasitologia , Reação em Cadeia da Polimerase/métodos , Animais , DNA de Protozoário/análise , Entamoeba/genética , Entamoeba histolytica/genética , Entamebíase/diagnóstico , Entamebíase/parasitologia , Humanos , Kit de Reagentes para Diagnóstico , Especificidade da EspécieRESUMO
In this study, a single-step duplex polymerase chain reaction procedure was developed for rapid, specific and sensitive identification of Entamoeba histolytica and for its diagnostic differentiation from E. dispar. Specific oligonucleotide primers were combined for the amplification of a cysteine proteinase 5 gene target sequence of 242 bp, present only in E. histolytica. Additionally, another oligonucleotide primer pair for both the E. histolytica and E. dispar actin gene target of 300 bp was designed to amplify only from amoebae DNA. The PCR developed was specific and efficiently identified and differentiated these parasites from each other in either cultured parasites or from stool material.