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The SMART Leish is a qualitative diagnostic real-time PCR test for the rapid detection of Leishmania species and the identification of L. major in skin lesion scrapings and punch biopsies from individuals suspected of having cutaneous leishmaniasis. The test utilizes real-time polymerase chain reaction assay on the Cepheid SmartCycler® II Dx to detect Leishmania species and L. major. The SMART Leish is indicated for use in patients with clinical presentations and travel history.

The SMART Leish consists of an assay reagent kit and assay definition files for the polymerase chain reaction (PCR) instrument platform. The kit contains sufficient reagents, in lyophilized bead form, to qualitatively assay 50 clinical samples for both Leishmania genus and L. major targets. Additional required accessories that are specified include the PCR instrument platform, a deoxyribonucleic acid (DNA) purification kit, and a positive extraction control. The device components and required accessories are listed as follows. For the Leishmania assays, a tissue specimen (skin scraping or punch biopsy) from an individual suspected of being infected with Leishmania species or L. major is collected in 70% or 100% ethanol, and the DNA is extracted from the specimen using the Qiagen QlAamp DNA Mini Kit. An aliquot of this DNA is tested using the Leishmania genus assay, which will amplify a portion of DNA encoding the Leishmania species 16S ribosomal ribonucleic acid (rRNA) gene if present. Amplified targets are detected using a TaqMan® hybridization probe with 6-carboxyfluorescein.(FAM) reporter dye (517 nm) and a Black Hole Quencher® (BHQ). This assay also contains a positive internal control consisting of a nonsensical, non-naturally occurring DNA sequence, with Texas Red reporter dye (615 nm) and BHQ, used to detect evidence of PCR inhibition and confirm the integrity of assay reagents in negative specimens. If the sample tests positive for Leishmania species, another aliquot of DNA may be tested using the L. major assay, which will amplify a portion of DNA encoding the GPI gene that is specific to L. major. Amplified targets are detected using a TaqMan hybridization probe with FAM reporter dye and a BHQ. The DNA amplification, detection of fluorescence, and interpretation of signals are done automatically by the SmartCycler instrument for each assay. The thermocycling protocols take approximately 45-55 minutes.