Loop-Mediated Isothermal Amplification Allows Rapid, Simple and Accurate Molecular Diagnosis of Human Cutaneous and Visceral Leishmaniasis Caused by Leishmania infantum When Compared to PCR

• Published in: Microorganisms (Basel) Vol. 9; no. 3; p. 610
• Main Authors: Ibarra-Meneses, Ana Victoria, Chicharro, Carmen, Sánchez, Carmen, García, Emilia, Ortega, Sheila, Ndung'u, Joseph Mathu, Moreno, Javier, Cruz, Israel, Carrillo, Eugenia
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 16.03.2021; MDPI
• Subjects: Bone marrow; Communication; Confidence intervals; cutaneous leishmaniasis; Deoxyribonucleic acid; Diagnosis; DNA; Fluorimetry; Fluorometers; Gene amplification; Genetic testing; Laboratories; LAMP; Leishmania; loop-mediated isothermal amplification; Loopamp; Parasites; Parasitic diseases; Polymerase chain reaction; Real time; Sensitivity; Vector-borne diseases; Visceral leishmaniasis; United States > US; Japan; Germany; Spain; Leishmania infantum; Loopamp; diagnosis; LAMP; loop-mediated isothermal amplification; cutaneous leishmaniasis; visceral leishmaniasis; PCR
• ISSN: 2076-2607; 2076-2607
• DOI: 10.3390/microorganisms9030610

Loop-mediated isothermal amplification allows the rapid, sensitive and specific amplification of DNA without complex and expensive equipment. We compared the diagnostic performance of Loopamp™ Detection Kit (Eiken Chemical Co., Ltd., Tokyo, Japan) with conventional and real-time polymerase chain reaction (PCR) for human cutaneous and visceral leishmaniasis caused by . A total of 230 DNA samples from cutaneous (CL) and visceral (VL) leishmaniasis cases and controls from Spain, characterized by nested PCR (LnPCR) were tested by: (i) the Loopamp™ Detection Kit (Loopamp), run on Genie III real-time fluorimeter (OptiGene, UK); and (ii) real-time quantitative PCR (qPCR). The Loopamp test returned 98.8% (95% confidence interval-CI: 96.0-100.00) sensitivity and specificity of 97.7% (95% CI: 92.2-100) on VL samples, and 100% (95% CI: 99.1-100) sensitivity and 100.0% (95% CI: 98.8-100.0) specificity on CL samples. The Loopamp time-to-positivity ( ) obtained by real-time fluorimetry showed excellent concordance (C = 97.91%) and strong correlation (r = 0.799) with qPCR's cycle threshold ( ). The performance of Loopamp is comparable to that of LnPCR and qPCR in the diagnosis of cutaneous and visceral leishmaniasis due to . The excellent correlation between the and should be further investigated to determine the accuracy of Loopamp to quantify parasite load in tissues.