RESUMO
Objective To explore the application of the TST-IGRA two-step method in the screening of close contacts of active tuberculosis patients among three high schools in Jinshan District in 2020-2021，and to provide evidence for improving the prevention and control of tuberculosis in schools. Methods Three school tuberculosis outbreaks in Jingshan District from 2020 to 2021 were included in the present study. After excluding active tuberculosis, tuberculin skin test and γ-interferon release assay (IGRA) were conducted to screen latent infection of Mycobacterium tuberculosis in close contacts, and the necessity of the two-step method was analyzed. Results A total of 362 close contacts were screened in the three outbreaks, and 350 people were tested by TST. Comparing the results of TST and IGRA among different types of close contacts, it was found that the positive rate of TST in teachers was higher than that in students（54.84% vs 20.38%，P<0.05）. The positive rate of TST among students from high-burden areas of pulmonary tuberculosis in Shanghai was higher than that of local students（24.71% vs 18.80%，P<0.05). IGRA detection was performed on those with moderate and strong positive TST results, and the results showed that the positive rate of IGRA in those with strong positive TST results was only 17.7%, with Kappa value of 0.3. Conclusion The prevention and control of tuberculosis in school should strengthen the annual health examination of teachers and staff, promote timely medical treatment for suspected tuberculosis symptoms, reasonably increase the screening frequency of students in high-burden areas of tuberculosis in Shanghai, and collect students’ previous history of tuberculosis exposure. When screening close contacts, after excluding active tuberculosis, it is recommended that TST and IGRA should be combined to determine latent Mycobacterium tuberculosis infection and achieve accurate intervention.
RESUMO
OBJECTIVE: To explore biomarkers for early auxiliary diagnosis of pneumoconiosis in coal workers(CWP) and its clinical significance. METHODS: Sixty-nine male coal miners exposed to dust were selected as control group, and sixty-seven CWP male patients were chosen as CWP group by purposive sampling method. Serum samples were collected from subjects of the two groups. The levels of malonaldehyde(MDA) and superoxide dismutase(SOD) were determined by colorimetric method. The enzyme-linked immunosorbent assay was used to measure the level of interleukin-6(IL-6) and tumor necrosis factor alpha(TNF-α). The acetylcholinesterase(AChE) activity was determined by modified Ellman method. The logistic regression model was used to analyze the risk factors of CWP. The receiver operating characteristic(ROC) curve was established to analyze the sensitive indicators in the pathogenesis of CWP. RESULTS: The serum SOD activity decreased(median: 65.1 vs 59.2 kU/L, P<0.05), and the MDA, IL-6 and TNF-α levels increased in the CWP group(median: 4.92 vs 6.68 μmol/L, 129.82 vs 163.18 ng/L, 63.90 vs 70.93 ng/L, P<0.05) compared with the control group. The logistic regression analysis results showed that AChE was the protective factor of CWP, while age, chronic respiratory symptoms, IL-6 and MDA were the risk factors of CWP(P<0.05). The ROC curve showed that IL-6 and MDA can be used as early indicators for the diagnosis of CWP in dust-exposed workers. CONCLUSION: The serum IL-6 and MDA levels can be used as biomarkers for early auxiliary diagnosis of CWP.
