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Updated: Jul 2, 2025
Synthesis, Characterization, and Application of Superparamagnetic Iron Oxide Nanoprobes for Extrapulmonary Tuberculosis Detection
Published on: February 16, 2020
Improving the diagnosis of active tuberculosis: a novel approach using magnetic particle-based chemiluminescence LAM
Yan Li1, Zhiwei Ru1, Hongxia Wei1
1Leide Biosciences Co., Ltd, Guangdong, China.
Objectives:
Tuberculosis (TB) is a significant global health concern, given its high rates of morbidity and mortality. The diagnosis using urine lipoarabinomannan (LAM) primarily benefits HIV co-infected TB patients with low CD4 counts. The focus of this study was to develop an ultra-sensitive LAM assay intended for diagnosing tuberculosis across a wider spectrum of TB patients.
Design & Methods:
To heighten the sensitivity of the LAM assay, we employed high-affinity rabbit monoclonal antibodies and selected a highly sensitive chemiluminescence LAM assay (CLIA-LAM) for development. The clinical diagnostic criteria for active TB (ATB) were used as a control. A two-step sample collection process was implemented, with the cutoff determined initially through a ROC curve. Subsequently, additional clinical samples were utilized for the validation of the assay.
Results:
In the assay validation phase, a total of 87 confirmed active TB patients, 19 latent TB infection (LTBI) patients, and 104 healthy control samples were included. Applying a cutoff of 1.043 (pg/mL), the CLIA-LAM assay demonstrated a sensitivity of 55.2% [95%CI (44.13%~65.85%)], and a specificity of 100% [95%CI (96.52%~100.00%)], validated against clinical diagnostic results using the Mann-Whitney U test. Among 11 hematogenous disseminated TB patients, the positive rate was 81.8%. Importantly, the CLIA-LAM assay consistently yielded negative results in the 19 LTBI patients.
Conclusion:
Overall, the combination of high-affinity antibodies and the CLIA method significantly improved the sensitivity and specificity of the LAM assay. It can be used for the diagnosis of active TB, particularly hematogenous disseminated TB.
