A Simple Microfluidic Assay for Diagnosing Tuberculous Meningitis in HIV-Uninfected Patients [Mycobacteriology and Aerobic Actinomycetes]

We evaluated the diagnostic performance of a simple and label-free pathogen enrichment method using homobifunctional imidoesters (HI) and a microfluidic system, called the SLIM assay, followed by real-time PCR from cerebrospinal fluid (CSF) in human immunodeficiency virus (HIV)-uninfected patients with suspected tuberculous meningitis (TBM). Patients with suspected TBM were prospectively enrolled in a tertiary hospital in an intermediate tuberculosis (TB)-burden country during a 30-month period. TBM was classified according to the uniform case definition. Definite and probable TBM were regarded as the reference standards for TBM, and possible TBM and not-TBM as the reference standards for not-TBM. Of 72 HIV-uninfected patients with suspected TBM, 10 were diagnosed with definite (n = 2) and probable (n = 8) TBM by the uniform case definition. The sensitivity of the SLIM assay was 100% (95% confidence interval [CI], 69 to 100%) compared with definite or probable TBM, and it was superior to those of mycobacterial culture (20% [95% CI, 3 to 56%]) and the Xpert MTB/RIF assay (0% [95% CI, 0 to 31%]). Of 21 possible TBM and 41 not-TBM patients by the uniform case definition, 5 possible TBM and no not-TBM patients gave positive results in the SLIM assay. The specificity of the SLIM assay was 92% (95% CI, 82 to 97%; 5/62). We demonstrated that the SLIM assay had a very high sensitivity and specificity with small samples of 10 cases of definite or probable TBM. Further studies are need...

Source: Journal of Clinical Microbiology - April 25, 2019 Category: Microbiology Authors: Park, J. H., Jin, C. E., Koo, B., Kwon, J.-S., Cha, H. H., Kim, J. Y., Noh, G. S., Koo, Y. S., Jeon, S.-B., Lee, S.-A., Shin, Y., Kim, S.-H. Tags: Mycobacteriology and Aerobic Actinomycetes Source Type: research