Diagnosis of tuberculous meningitis using a combination of peripheral blood T-SPOT.TB and cerebrospinal fluid interferon-c detection methods

Abstract

Objective: To evaluate the effectiveness of combined peripheral blood T-SPOT.TB and cerebrospinal fluid interferon-c (cIFN-c) detection methods in the diagnosis of tuberculous meningitis (TBM). Methods: A total of 30 individuals with TBM and 39 control individuals without TBM participated in this study. IFN-c secreting T cells were detected by enzyme-linked immunospot (ELISPOT), and cIFN-c was detected by enzyme-linked immunosorbent assay (ELISA). We collected cerebrospinal fluid from 10 patients in the TBM group on initial visit and at 4 weeks, to observe changes. Results: The sensitivity and specificity of peripheral-blood T-SPOT.TB testing in the diagnosis of TBM were 70% and 87%, respectively. The area under the ROC curve of cIFN-c for TBM diagnosis was 0.819, and the corresponding sensitivity and specificity were 83% and 85%, respectively. When T-SPOT.TB and cIFN-c results were positive, the specificity and positive predictive value of TBM diagnosis reached 100%. Conclusions: Combined use of T-SPOT.TB and cIFN-c could improve the diagnosis efficiency of TBM. Dynamic observation of cIFN-c is also important in monitoring TBM because the level of this analyte significantly decreases after treatment.