Polymerase chain reaction procedure to detect Trypanosoma cruzi in blood samples from chronic chagasic patients

The feasibility of DNA amplification by the polymerase chain reaction for specific detection of Trypanosoma cruzi in human blood was investigated. We have used primers flanking a 220-bp fragment of highly repetitive elements, the E13 element, in T. cruzi nuclear DNA. Only polymerase chain reaction products from blood samples of chronic chagasic patients showed several amplified fragments in 1.6% agarose gels stained with ethidium bromide. Southern blot analysis demonstrated that the 220-bp amplified fragment is specific for T. cruzi DNA and very useful to detect the presence of the parasite in blood from chronic chagasic patients.