A novel non-invasive diagnostic approach based on urine and blood: a cross-sectional study combining lipoarabinomannan antigen and interferon-gamma release assay for active tuberculosis

The combination of urine LAM antigen testing and blood-based IGRA optimizes TB diagnosis by simultaneously targeting two distinct dimensions: pathogen-derived antigens and host immune response. The parallel testing improves sensitivity for screening, while the serial testing enhances specificity for confirmatory diagnosis. This strategy offers a non-invasive approach with ease of sample collection, demonstrating particular value in diagnosing challenging cases such as sputum smear-negative pulmonary TB, extrapulmonary TB, and TB in immunocompromised patients.