Evaluation of Loopamp™MTBC detection kit for diagnosis of pulmonary tuberculosis at a peripheral laboratory in a high burden setting

Diagn Microbiol Infect Dis. 2018 Mar;90(3):190-195. doi: 10.1016/j.diagmicrobio.2017.11.009. Epub 2017 Nov 21.

Abstract

The Loopamp™MTBC detection kit (TB-LAMP) was designed to replace the sputum smear microscopy for the diagnosis of pulmonary tuberculosis. We evaluated its performance at a peripheral laboratory in Vietnam. The sensitivity of TB-LAMP was 45.5% (28.1%-63.6%), which was equal to 3-sputum smear microscopy but lower than that of Xpert MTB/RIF (87.8% [71.8%-96.6%]). In patients with culture-confirmed TB, sensitivity was 80% (51.9%-95.7%) in smear-positive and 16.7% (3.5%-41.4%) in smear-negative cases. The specificity of TB-LAMP was 95.1% (92.7%-96.9%), which was lower than that of smear microscopy (98.9% [97.5%-99.7%]) and Xpert MTB/RIF (99.3% [98.1%-99.9%]) (P<0.05). The probability of TB detection by TB-LAMP was more influenced by sample quality and viscosity than were smear microscopy, Xpert MTB/RIF, and culture. The present data do not support the use of TB-LAMP as a replacement test for smear microscopy in peripheral laboratories.

Keywords: Diagnosis; Evaluation; Microscopy center; Peripheral laboratory; TB-LAMP; Tuberculosis.

Publication types

  • Evaluation Study

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Child, Preschool
  • Female
  • Humans
  • Infant
  • Male
  • Middle Aged
  • Mycobacterium tuberculosis / genetics*
  • Nucleic Acid Amplification Techniques / methods*
  • Sensitivity and Specificity
  • Sputum / microbiology
  • Tuberculosis, Multidrug-Resistant / diagnosis*
  • Tuberculosis, Multidrug-Resistant / microbiology
  • Tuberculosis, Pulmonary / diagnosis*
  • Tuberculosis, Pulmonary / microbiology
  • Vietnam
  • Young Adult