Integrated nucleic acid testing system to enable TB diagnosis in peripheral settings

Area of Science:

• Medical Diagnostics
• Biotechnology
• Infectious Disease Research

Background:

• Tuberculosis (TB) diagnosis requires rapid, affordable methods for high-burden, low-resource settings.
• Current diagnostic tools often lack the speed and accessibility needed for timely intervention.

Purpose of the Study:

• To develop an integrated nucleic acid testing device for rapid Mycobacterium tuberculosis (M.tb) detection in sputum.
• To enable near-patient diagnosis in resource-limited areas to facilitate treatment and limit TB transmission.

Main Methods:

• A prototype device automates sputum lysis, nucleic acid extraction, isothermal DNA amplification, and lateral flow detection.
• The closed-system, single-use cartridge processes liquefied sputum samples in under 1.5 hours.
• Utilizes bead-blender technology for cell disruption and a miniature bead blender for lysis.

Main Results:

• The system demonstrated a limit of detection of 5 × 10^3 CFU/mL for M.tb-spiked sputum.
• Testing on clinical samples showed preliminary sensitivity of 90% and specificity of 96% compared to qPCR.
• No false-positive results were observed in sputum-only controls.

Conclusions:

• The integrated nucleic acid testing device shows promise for rapid TB diagnosis in resource-limited settings.
• Further development could enable same-encounter diagnosis and treatment initiation for TB patients.
• This technology has the potential to significantly impact TB control in high-burden countries.