Diagnostic value of Treponema pallidum antibody index detected by electrochemiluminescence immunoassay in neurosyphilis
10.3760/cma.j.cn112309-20230619-00180
- VernacularTitle:电化学发光免疫法测定梅毒螺旋体抗体指数在神经梅毒诊断中的应用
- Author:
Sirui WU
1
;
Yuanfang WANG
;
Lan LUO
;
Jielun DENG
;
Dongdong LI
;
Yi XIE
Author Information
1. 四川大学华西临床医学院，成都 610041
- Keywords:
Neurosyphilis;
Antibody index;
Intrathecal specific antibody;
Diagnostic value
- From:
Chinese Journal of Microbiology and Immunology
2024;44(6):545-552
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To evaluate the value of Treponema pallidum ( Tp)-specific antibody index in the diagnosis, staging, and typing of neurosyphilis (NS). Methods:Fifty patients diagnosed with NS at the West China Hospital of Sichuan University from March 2020 to December 2022 were recruited as the experimental group, and 50 non-NS syphilis patients were enrolled during the same period as the control group. Cerebrospinal fluid (CSF) and matched serum samples along with clinical data were collected. Clinical and Laboratory Standards Institute (CLSI) EP06-Ed2 file was used to analyze the linear range of electrochemiluminescence immunoassay for Tp-specific antibody detection, and the Tp antibody index was calculate for all subjects. The correlation of Tp antibody index, IgG index, IgG synthesis rate, and albumin quotient with other clinical indicators was evaluated by the coefficient of correlation, and the diagnostic efficacy of these indicators in NS was analyzed using the receiver operating characteristic (ROC) curve. Results:All the deviations from linearity of electrochemiluminescence immunoassay for detecting Tp antibodies in serum and CSF samples were within the allowable deviation from linearity. Compared with the non-NS group, the NS group showed a significant increase in the Tp antibody index ( P<0.05), with no significant differences observed among the groups of different subtypes, severity, or receiving treatment or not ( P>0.05). Tp antibody index, IgG index, and IgG synthesis rate were positively correlated with serum Tp antibody, CSF Tp antibody, trace protein, and nucleated cell count ( P<0.05). Taking 14.99 as the cut-off value for NS diagnosis, the diagnostic sensitivity of Tp antibody index was 74.0% (95%CI: 60.5%-84.1%), and the specificity was 94.0% (95%CI: 83.8%-98.4%), with the area under the ROC curve of 0.897, which was larger than that of albumin quotient, IgG index, and IgG synthesis rate. Conclusions:This study finds a significant increase in the Tp antibody index in NS patients with good diagnostic sensitivity and specificity, providing reference for the diagnosis of NS.
