PCR detection and identification of Leishmania parasites in clinical specimens in Ecuador: a comparison with classical diagnostic methods.

A simplified polymerase chain reaction (PCR)-based assay was used for detection and typing of Leishmania parasites in clinical specimens from patients suspected of cutaneous leishmaniasis. Using cultures as the reference standard, our PCR detection method was more sensitive (92%) than classical diagnostic techniques, including microscopy (42% sensitivity), histologic staining (33%), and IgG enzyme-linked immunosorbent (20%). The PCR assay was also 100% specific. Parasites in both lesion biopsies and isolates cultured from lesion aspirates were identified as Leishmania braziliensis by PCR. In this study, we have demonstrated the suitability of simplified PCR assays for the simultaneous diagnosis and typing of parasites causing cutaneous leishmaniasis in a developing country where leishmaniasis is endemic.