{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,22]],"date-time":"2025-10-22T00:39:00Z","timestamp":1761093540313,"version":"build-2065373602"},"reference-count":60,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,10,21]],"date-time":"2025-10-21T00:00:00Z","timestamp":1761004800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:sec><jats:title>Introduction<\/jats:title><jats:p>Pyrazinamide (PZA) is a critical component of first-line tuberculosis (TB) treatment. Misdiagnosis of PZA resistance can lead to serious consequences, highlighting the need for accurate and reliable PZA susceptibility testing. While broth microdilution is a cost-effective and widely used method for determining the minimum inhibitory concentrations (MICs) of antibiotics, its current application for PZA has been limited by the requirement for acidic conditions in conventional <jats:italic>Mycobacterium tuberculosis<\/jats:italic> culture media.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>In this study, we determined the MICs of PZA against the clinical isolates of pyrazinamidase-positive <jats:italic>M. tuberculosis<\/jats:italic> at a neutral pH of 6.8 using a defined culture medium and the standard protocol of the broth microdilution method.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>The results showed that PZA MICs could be reliably determined in <jats:italic>M. tuberculosis<\/jats:italic> clinical isolates, with values ranging from \u226412.5 to 100\u202f\u03bcg\/mL.<\/jats:p><\/jats:sec><jats:sec><jats:title>Discussion<\/jats:title><jats:p>This approach overcomes the limitations of existing acidic pH-based PZA susceptibility tests and provides a reliable, accurate, cost-effective method for detecting improved PZA resistance. Implementing this method could significantly enhance TB treatment, resistance surveillance, and efforts to combat drug-resistant TB.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fmicb.2025.1688772","type":"journal-article","created":{"date-parts":[[2025,10,21]],"date-time":"2025-10-21T11:56:56Z","timestamp":1761047816000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Determining the minimum inhibitory concentrations of pyrazinamide against Mycobacterium tuberculosis clinical isolates at a neutral pH of 6.8 using the broth microdilution method"],"prefix":"10.3389","volume":"16","author":[{"given":"Maria","family":"Tamblin","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wanliang","family":"Shi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Liang","family":"Chen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jessica","family":"Reynolds","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2025,10,21]]},"reference":[{"key":"ref1","volume-title":"Issues in mycobacterium tuberculosis complex (MTBC) drug susceptibility testing: pyrazinamide (PZA). 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