Evaluation of PCR assay in diagnosis and identification of cutaneous leishmaniasis: a comparison with the parasitological methods.

The aims of this study are to identify Leishmania species and compare and validate internal transcribed spacers (ITS) polymerase chain reaction (PCR) assay against parasitological methods for diagnosing cutaneous leishmaniasis (CL). We used the ITS-PCR, parasite culture, and microscopic evaluation of stained smears on 155 specimens from suspected cases of (CL) patients who referred to Mashhad Health Centers (northeast Iran). The PCR indicated the sensitivity (98.8%), correctly diagnosing 86 of the 87 confirmed positive specimens. Microscopy and parasite culture alone showed 79.3% sensitivity (69/87 positive) and 86.2% sensitivity (75/87 positive), respectively, while microscopy and culture in combination improved sensitivity totally to 100% (87/87). The results also revealed that Leishmania tropica species is dominant (96.5%) in the studied regions. This study suggests that both the parasitological techniques reliably were used for the diagnosis of CL, and the ITS-PCR assay without using RFLP analysis is useful for identifying Leishmania species in the area.