Breakthrough Portable TB Test Demonstrates Perfect Accuracy in Clinical Samples

Researchers at Princeton University and collaborating institutions have developed an innovative diagnostic tool called SHINE-TB, a portable and rapid test designed to detect Mycobacterium tuberculosis—the bacteria responsible for tuberculosis (TB)—directly from sputum samples. This groundbreaking assay employs a combination of CRISPR-based detection and isothermal amplification, enabling highly sensitive and specific diagnosis without the need for complex laboratory equipment.

The SHINE-TB assay utilizes a parallelized reaction process that amplifies bacterial DNA and detects it via CRISPR-Cas12a and Cas13a mechanisms. It specifically targets two conserved genetic sequences of M. tuberculosis, IS6110 and IS1081, along with an internal human DNA control to ensure accuracy. The process is streamlined into a single reaction conducted at 37°C, simplifying sample preparation and analysis.

Clinical validation was performed on 13 blinded sputum samples obtained from symptomatic adults in primary healthcare settings in Cali, Colombia. The results were remarkable, achieving 100% sensitivity and 100% specificity compared to traditional culture methods. The assay demonstrated a detection limit of approximately 69 CFU/ml for the M. tuberculosis strain H37Rv and 80.5 CFU/ml for M. bovis BCG in spiked sputum samples, with no cross-reactivity to other bacteria or fungi.

Compared to existing molecular tests like GeneXpert Ultra, which also showed high sensitivity but slightly lower specificity (86%), SHINE-TB provides a cost-effective, equipment-free alternative suitable for low-resource environments. The test results can be read visually on simple paper strips, and the test kits can be freeze-dried for storage and transport without refrigeration.

This development aligns with the World Health Organization’s benchmarks for point-of-care TB diagnostics, aiming for at least 85% sensitivity and 90% specificity. The compact design and minimal equipment requirements make SHINE-TB a promising tool for expanding access to rapid TB diagnosis, especially in underserved settings where traditional testing infrastructure is not available.

Source: https://medicalxpress.com/news/2025-08-portable-tuberculosis-sensitivity-specificity-clinical.html