Molecular dipstick test for diagnosis of sleeping sickness

J Clin Microbiol. 2006 Aug;44(8):2884-9. doi: 10.1128/JCM.02594-05.

Abstract

Human African trypanosomiasis (HAT) or sleeping sickness is a neglected disease that affects poor rural populations across sub-Saharan Africa. Confirmation of diagnosis is based on detection of parasites in either blood or lymph by microscopy. Here we present the development and the first-phase evaluation of a simple and rapid test (HAT-PCR-OC [human African trypanosomiasis-PCR-oligochromatography]) for detection of amplified Trypanosoma brucei DNA. PCR products are visualized on a dipstick through hybridization with a gold-conjugated probe (oligochromatography). Visualization is straightforward and takes only 5 min. Controls both for the PCR and for DNA migration are incorporated into the assay. The lower detection limit of the test is 5 fg of pure T. brucei DNA. One parasite in 180 microl of blood is still detectable. Sensitivity and specificity for T. brucei were calculated at 100% when tested on blood samples from 26 confirmed sleeping sickness patients, 18 negative controls (nonendemic region), and 50 negative control blood samples from an endemic region. HAT-PCR-OC is a promising new tool for diagnosis of sleeping sickness in laboratory settings, and the diagnostic format described here may have wider application for other infectious diseases.

Publication types

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

MeSH terms

  • Animals
  • Base Sequence
  • Blood / parasitology
  • DNA, Protozoan / analysis*
  • DNA, Protozoan / genetics
  • DNA, Protozoan / isolation & purification
  • Humans
  • Molecular Diagnostic Techniques*
  • Molecular Sequence Data
  • Nucleic Acid Hybridization / methods*
  • Polymerase Chain Reaction / methods*
  • Reference Standards
  • Sensitivity and Specificity
  • Trypanosoma brucei brucei / genetics
  • Trypanosoma brucei brucei / isolation & purification*
  • Trypanosomiasis, African / diagnosis*

Substances

  • DNA, Protozoan