Tuberculosis (TB) is a significant cause of morbidity and mortality worldwide. The patient compliance with the long treatment regimens is essential for successful eradication. Pyrazinamide (PZA) shortens these regimens from 9 to 6 months, and therefore, improves treatment completion rates. Although PZA is a first-line medication for the treatment of TB, no simple or reliable assay to determine PZA resistance is yet available. In the presence of PZA, only susceptible Mycobacterium tuberculosis strains release pyrazinoic acid (POA). Therefore, the measurement and quantification of released POA is an indicator of PZA resistance.

The initial development of the algorithm was funded by a Wellcome Trust Career Development Fellowship awarded to DAJM [078067/Z/05] and by the Peruvian FINCYT Proyecto de Interes Nacional [PIN 061] and CONCYTEC PROCYT awarded to MZ. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.