Tehran University of Medical Sciences Iranian Journal of Parasitology 1735-7020 9 1 2014 03 15 50 59 EN Mehrdad Ghasemian Department of Parasitology and Mycology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran. Mohammad Javad Gharavi Department of Parasitology, Faculty of Allied Medicine, Iran University of Medical Sciences, Tehran, Iran. Lame Akhlaghi Department of Parasitology and Mycology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran. Mehdi Mohebali Department of Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Ahmad Reza Meamar Department of Parasitology and Mycology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran. Ehsan Aryan Antimicrobial Resistance Research Center, Department of Medical Microbiology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Hormozd Oormazdi Department of Parasitology and Mycology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran. 2015 10 14   Background: Parasitological methods for the diagnosis of Visceral leishmania-sis (VL) require invasive procedures, so serological and molecular approaches have been developed but are not generally applicable in the field. We evaluated a loop mediated isothermal amplification (LAMP) assay using blood from VL pa-tients and compared it to nested PCR. Methods: Forty-seven subjects with clinical features (fever, hepatosplenomegaly and anemia) were confirmed positive for VL by the direct agglutination test (DAT) at titers >3200. Forty DAT negative individuals from non-endemic areas with no clinical signs or symptoms of VL served as controls. A LAMP assay was performed using a set of six primers targeting Leishmania infantum kinetoplast DNA (kDNA) minicircle gene under isothermal (64 °C) conditions. For nested PCR we used primers targeting the kDNA minicircle gene. Results: The LAMP assay provided a detection limit of 1 parasite in 1 ml of peripheral blood and detected L. infantum DNA in 44 of 47 DAT-confirmed VL cases, with diagnostic sensitivity of 93.6% (95% CI). No L. infantum DNA was amplified in controls, indicating a specificity of 100%. The nested PCR yielded sensitivity of 96% (95% CI) and a specificity of 100% (95% CI). Conclusion: The LAMP assay gave results similar to those of nested PCR but in a shorter time. The LAMP method is simple; requires no sophisticated equip-ment; has a short reaction time; and results, indicated by turbidity of the reaction mixture, are observable with the naked eye. https://ijpa.tums.ac.ir/index.php/ijpa/article/view/433 https://ijpa.tums.ac.ir/index.php/ijpa/article/download/433/305