Next-generation Diagnostics for Melioidosis: Evaluation of a Prototype i-STAT Cartridge to Detect Burkholderia pseudomallei Biomarkers

Kevin L. Schully, Charles C. Young, Mark Mayo, Amy L. Connolly, Vanessa Rigas, Ammarah Spall, Alyssa A. Chan, Mark G. Salvador, James V. Lawler, Jason A. Opdyke, Danielle V. Clark, Bart J. Currie

    Research output: Contribution to journalArticle

    2 Citations (Scopus)

    Abstract

    Background: Infection with the gram-negative bacterium Burkholderia pseudomallei can result in melioidosis, a life-threatening disease that can be difficult to diagnose. Culture remains the gold standard for diagnosis but requires laboratory resources not available in many endemic regions. A lateral flow immunoassay has shown promise for POC diagnostics but suffers from low sensitivity when used on blood samples. PCR also has low sensitivity on blood, attributed to the low bacterial numbers in blood observed in melioidosis patients, even when bacteraemic. Methods: A prototype i-STAT cartridge was developed to utilize the monoclonal antibody specific for the capsule of pathogenic Burkholderia species employed on the LFI. The resulting POC assay was evaluated on 414 clinical specimens from Darwin, Australia and Cambodia. Results: The i-STAT assay accurately distinguished Australian blood culture positive melioidosis patients from Australian patients hospitalized with other infections (AUC = 0.91, 95% CI 0.817 - 1.0). We derived an assay cutoff with 76% sensitivity and 94% specificity that correctly classified 88% (n = 74) of the Australian patients. Interestingly, only 46% (6/13) of the culture-positive melioidosis patients in Cambodia were classified correctly. Of great importance however, the assay detected capsule from blood samples for 32% of blood culture negative melioidosis patients in both cohorts and previously undiagnosed melioidosis patients in Cambodia. In addition the assay showed high sensitivity and specificity for urine, pus and sputum. Conclusions: Diagnostic tools that are not dependent upon the growth kinetics or the levels of bacteremia of B. pseudomallei represent the next-generation of diagnostics and must be pursued further.

    Original languageEnglish
    Pages (from-to)421-427
    Number of pages7
    JournalClinical Infectious Diseases
    Volume69
    Issue number3
    DOIs
    Publication statusPublished - 1 Aug 2019

    Bibliographical note

    This work is written by (a) US Government employee(s) and is in the public domain in the US.

    Keywords

    • Burkholderia pseudomallei
    • diagnostic
    • melioidosis
    • point of care

    Fingerprint Dive into the research topics of 'Next-generation Diagnostics for Melioidosis: Evaluation of a Prototype i-STAT Cartridge to Detect Burkholderia pseudomallei Biomarkers'. Together they form a unique fingerprint.

  • Cite this

    Schully, K. L., Young, C. C., Mayo, M., Connolly, A. L., Rigas, V., Spall, A., Chan, A. A., Salvador, M. G., Lawler, J. V., Opdyke, J. A., Clark, D. V., & Currie, B. J. (2019). Next-generation Diagnostics for Melioidosis: Evaluation of a Prototype i-STAT Cartridge to Detect Burkholderia pseudomallei Biomarkers. Clinical Infectious Diseases, 69(3), 421-427. https://doi.org/10.1093/cid/ciy929