Diagnostic Significance Of Interferon γ,interleukin-33,and Interleukin-35 In Tuberculous Pleural Effusion

Objective:The contents of IFN-γ,IL-33 and IL-35 in different pleural effusion were determined to investigate their role in the diagnosis of tuberculous pleural effusion.Methods:According to the inclusion criteria of this study,there were 41 cases of pleural effusion of unknown etiology but clearly diagnosed by thoracentesis drainage and pathology by thoracoscopy were selected for treatment at the Department of Respiratory and Critical Care Medicine of the Second Hospital of Jilin University between September 2020 and January 2023.The pleural fluid of the respondents was collected and the levels of IFN-γ,IL-33 and IL-35 in the pleural fluid of patients with different types of diseases were measured using enzyme-linked immunosorbent assay(ELISA).The results of the test were correlated and processed using SPSS.27 software,and the working characteristic curves(ROC curves)of the patients were plotted and the underline regions of each index were compared to derive the best diagnostic The critical values and the corresponding specificity and sensitivity were compared to comprehensively evaluate the role of interferon-γ,IL-33 and IL-35 in the diagnosis of tuberculous pleurisy.Results:1.For comparison of the concentration levels of IFN-γin the three groups of different types of pleural effusions,the highest concentration level was 222.59(98.71,490.52)pg/ml in the tuberculosis group,followed by 187.08(103.88,358.23)pg/ml in the inflammatory group,followed by 27.58(14.66,37.05)pg/ml in the malignant group.27.58(14.66,37.05)pg/ml,with statistically significant differences(P<0.001),and the tuberculosis group was compared with the remaining two groups in a two-by-two comparison,respectively(P<0.05).According to the results of the ROC curve analysis of interferon-gamma,it can be concluded that the AUC,i.e.the area under the ROC curve,is 0.723,which corresponds to a critical value of 200.23 pg/ml for the diagnosis of differentiating tuberculous from non-tuberculous pleural effusion,with a sensitivity of 64.71%and a specificity of 79.17%.2.When comparing the concentration levels of IL-33 in the three groups of different types of pleural effusions,the highest concentration level was 81.66(44.45,147.59)pg/ml in the tuberculosis group,followed by 72.26(23.24,95.93)pg/ml in the inflammatory group and 38.37(31.56,51.23)pg/ml in the malignant group.33concentrations were not statistically significant(P=0.062)and when comparing between groups,the difference in IL-33 concentrations was statistically significant in the TB group compared to the malignant group(P=0.018).the area under the subject working characteristic curve for IL-33 was 0.684 and its threshold for diagnosing TB versus non-TB pleural fluid was 77.73 pg/ml with a sensitivity of 52.94%and specificity was 83.33%.3.For the comparison of the concentration levels of IL-35 in the different types of pleural effusion in the 3 groups,the concentration levels in the tuberculosis group The highest level was 69.46(38.27,144.33)pg/ml,followed by 52.14(27.65,88.56)pg/ml in the inflammatory group and 40.30(29.31,53.55)pg/ml in the malignant group.There was no significant difference between the three groups(P=0.095),while the difference between the tuberculosis and malignant groups was statistically significant(P=0.031).The area under the ROC curve for IL-35 was 0.686 and its cut-off value for differential diagnosis of tuberculous versus non-tuberculous pleural fluid was 60.79pg/ml,with a sensitivity of 70.59%and a specificity of 70.83%.4.The sensitivity and specificity of IFN-γ,interleukin-33 and interleukin-35 in pleural water were 94.12%and 50%respectively which was higher than the sensitivity of the three cytokines measured individually,with statistically significant differences(X~2=25.802,P<0.001.X~2=43.152,P<0.001;X~2=18.320,P<0.001).When the three were combined in a series,the sensitivity was 29.41%and the specificity was 95.83%,which was higher than that of IFN-γ,IL-33 and IL-35 alone,all with statistically significant differences(X~2=13.211,P<0.001;X~2=8.992,P=0.003;X~2=22.682,P<0.001).Conclusion:1.The concentration level of IFN-γin the tuberculosis group was higher than that in the malignant group and the inflammatory group,which proved that it was related to the differential diagnosis of tuberculous pleural effusion.2.The concentrations of IL-33 and IL-35 in tuberculous pleural fluid were greater than those in malignant pleural fluid,and the difference was statistically significant,indicating that the cytokines have value in the differential diagnosis of tuberculosis and malignancy.3.Combined measurement of IFN-γ,IL-33 and IL-35 levels in the patient’s pleural fluid is important in the diagnosis and exclusion of pleural tuberculosis.The combination of IFN-γ,IL-33 and IL-35 levels in patients’pleural fluid is important for the diagnosis and exclusion of pleural TB.