Clinical Evaluation of a Blood Assay to Diagnose Paucibacillary Tuberculosis via Bacterial Antigens

Tuberculosis is a prevalent and potentially deadly infectious disease with a worldwide incidence of more than 10 million new cases each year, and in 2015 alone, 1.4 million deaths were attributed to TB.  Much of the world relies on microbiologic techniques to detect tuberculosis including smear microscopy and mycobacterial culture which has a very long sample to answer timeframe. Both methods also have low clinical sensitivity for paucibacillary TB cases which account for more than 60% of new TB cases each year in emerging endemic areas such as China.  PCR-based methods are faster but also have limitations.  In the May 2018 issue of Clinical Chemistry, Dr. Tony Hu and his colleagues described a new peptide-based approach to detecting TB that overcomes those issues by using antibody conjugated nanoparticles, or nanodiscs, to bind specific peptides present in digested serum samples from cases of tuberculosis.  These are then detected by benchtop matrix-assisted laser desorption ionization-time-of-flight mass spectrometry, or MALDI-TOF MS.