Highly sensitive detection of malaria parasitemia in a malaria-endemic setting: performance of a new loop-mediated isothermal amplification kit in a remote clinic in Uganda

J Infect Dis. 2013 Aug 15;208(4):645-52. doi: 10.1093/infdis/jit184. Epub 2013 Apr 30.


Background: Current malaria diagnostic tests, including microscopy and antigen-detecting rapid tests, cannot reliably detect low-density infections. Molecular methods such as polymerase chain reaction (PCR) are highly sensitive but remain too complex for field deployment. A new commercial molecular assay based on loop-mediated isothermal amplification (LAMP) was assessed for field use.

Methods: Malaria LAMP (Eiken Chemical, Japan) was evaluated for samples from 272 outpatients at a rural Ugandan clinic and compared with expert microscopy, nested PCR, and quantitative PCR (qPCR). Two technicians performed the assay after 3 days of training, using 2 alternative blood sample-preparation methods and visual interpretation of results by fluorescence assay.

Results: Compared with 3-well nested PCR, the sensitivity of both LAMP and single-well nested PCR was 90%; the microscopy sensitivity was 51%. For samples with a Plasmodium falciparum qPCR titer of ≥ 2 parasites/µL, LAMP sensitivity was 97.8% (95% confidence interval, 93.7%-99.5%). Most false-negative LAMP results involved samples with parasitemia levels detectable by 3-well nested PCR but very low or undetectable by qPCR.

Conclusions: Malaria LAMP in a remote Ugandan clinic achieved sensitivity similar to that of single-well nested PCR in a United Kingdom reference laboratory. LAMP dramatically lowers the detection threshold achievable in malaria-endemic settings, providing a new tool for diagnosis, surveillance, and screening in elimination strategies.

Keywords: Africa; DNA; LAMP; PCR; Plasmodium falciparum; Uganda; diagnosis; loop-mediated isothermal amplification; malaria; molecular diagnosis; polymerase chain reaction; sensitivity and specificity.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Child
  • Child, Preschool
  • Endemic Diseases
  • Female
  • Humans
  • Malaria, Falciparum / diagnosis*
  • Malaria, Falciparum / epidemiology*
  • Male
  • Middle Aged
  • Molecular Diagnostic Techniques / methods*
  • Nucleic Acid Amplification Techniques / methods*
  • Parasitemia / diagnosis*
  • Parasitology / methods*
  • Plasmodium falciparum / isolation & purification*
  • Rural Population
  • Sensitivity and Specificity
  • Uganda
  • Young Adult