Rapid diagnosis of Leishmania infection with a portable loop-mediated isothermal amplification device

Puri, Madhu; Brar, Harsimran Kaur; Mittal, Nimisha; Madan, Evanka; Srinivasan, Rajesh; Rawat, Kapil; Moulik, Srija; Chatterjee, Mitali; Gorthi, Sai Siva; Muthuswami, Rohini; Madhubala, Rentala

L. donovani is an intracellular protozoan parasite, that causes visceral leishmaniasis (VL), and consequently, post-kala azar dermal leishmaniasis (PKDL). Diagnosis and treatment of leishmaniasis is crucial for decreasing its transmission. Various diagnostic techniques like microscopy, enzyme-linked immunosorbent assays (ELISA) and PCR-based methods are used to detect leishmaniasis infection. More recently, loop-mediated isothermal amplification (LAMP) assay has emerged as an ideal diagnostic measure for leishmaniasis, primarily due to its accuracy, speed and simplicity. However, point-of-care diagnosis is still not been tested with the LAMP assay. We have developed a portable LAMP device for the monitoring of Leishmania infection. The LAMP assay performed using our device can detect and amplify as little as 100 femtograms of L. donovani DNA. In a preliminary study, we have shown that the device can also amplify L. donovani DNA present in VL and PKDL patient samples with high sensitivity (100%), specificity (98%) and accuracy (99%), and can be used both for diagnostic and prognostic analysis. To our knowledge, this is the first report to describe the development and application of a portable LAMP device which has the potential to evolve as a point-of-care diagnostic and prognostic tool for Leishmania infections in future. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12038-021-00211-0.