A NEW smartphone-sized device developed by Tulane University researchers delivers rapid tuberculosis (TB) diagnoses in under an hour using saliva, blood, or sputum samples, addressing critical gaps in paediatric TB detection where over half of cases go undiagnosed, according to a study published in Science Translational Medicine.
TB remains the world’s deadliest infectious disease, with 10 million annual infections and 4.2 million undiagnosed cases in 2021, disproportionately affecting children in low-resource settings. Current diagnostic tools, such as GeneXpert MTB/RIF, are costly and rely on sputum samples, which are difficult to obtain from children. The lab-in-tube assay (LIT) system—a portable, battery-powered device costing under $800—uses CRISPR-Cas12a and recombinase polymerase amplification to detect Mycobacterium tuberculosis (Mtb) DNA with single-nucleotide specificity. Validated in a cohort of children aged 1–16, the LIT achieved 81% sensitivity and 94% specificity in serum samples, outperforming GeneXpert (68% sensitivity) and meeting WHO criteria for nonsputum diagnostics. In adults, it matched reference methods using saliva and sputum. The device also identified rifampin-resistant strains and tracked treatment responses through declining Mtb DNA levels in serial blood tests.
These findings highlight the LIT’s potential to transform TB management in resource-limited regions. Clinicians should prioritise its deployment for paediatric and HIV-coinfected patients, who often lack sputum production. Future implementations must focus on training healthcare workers in saliva-based testing and integrating the device into community health programmes. Further studies should explore its scalability in diverse high-burden settings and adaptation for other infectious diseases.
Reference
Youngquist B et al. Rapid tuberculosis diagnosis from respiratory or blood samples by a low cost, portable lab-in-tube assay. Science Translational Medicine. 2025;DOI:10.1126/scitranslmed.adp6411.
