title: Development and Assessment of Loop-Mediated Isothermal Amplification (LAMP) Assay for the Diagnosis of Human Visceral Leishmaniasis in Iran.
abstract: BACKGROUND
  Parasitological methods for the diagnosis of Visceral leishmaniasis (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 patients 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).
  
  
  CONCLUSIONS
  The LAMP assay gave results similar to those of nested PCR but in a shorter time. The LAMP method is simple; requires no sophisticated equipment; has a short reaction time; and results, indicated by turbidity of the reaction mixture, are observable with the naked eye.
authors: Department of Parasitology and Mycology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
authors: Mehrdad
authors: M
authors: Ghasemian
authors: Department of Parasitology, Faculty of Allied Medicine, Iran University of Medical Sciences, Tehran, Iran.
authors: Mohammad Javad
authors: MJ
authors: Gharavi
authors: Department of Parasitology and Mycology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
authors: Lame
authors: L
authors: Akhlaghi
authors: Department of Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors: Mehdi
authors: M
authors: Mohebali
authors: Department of Parasitology and Mycology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
authors: Ahmad Reza
authors: AR
authors: Meamar
authors: Antimicrobial Resistance Research Center, Department of Medical Microbiology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors: Ehsan
authors: E
authors: Aryan
authors: Department of Parasitology and Mycology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
authors: Hormozd
authors: H
authors: Oormazdi
keywords: Human; Iran; LAMP; Nested PCR; Peripheral blood; Visceral leishmaniasis
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