Objective:To evaluate the risk of developing pulmonary tuberculosis (PTB) among individuals with latent tuberculosis infection (LTBI) in schools and the protective effect of tuberculosis preventive treatment (TPT).Methods:A retrospective cohort study was conducted to collect data on 15 school outbreaks that occurred in Guangdong Province from 2017 to 2021. Baseline information on tuberculin skin test (TST) or interferon-gamma release test (IGRA) was obtained during contact surveys, as well as baseline information such as TPT. The incidence of PTB between 2017 and 2022 was queried using the Chinese Center for Disease Control and Prevention Information System. Poisson regression analysis was used to compare the incidence risk of PTB in the LTBI population under different TST states at baseline. Current cases, new cases and all cases (the sum of the two) were used as dependent variables. Cox regression models were used to analyze various risk factors affecting the risk of PTB in the LTBI population and evaluate the protective effect of TPT.Results:A total of 6 550 contacts were included in this study, of which 409 received TPT. Within 0-3 months after baseline survey, 119 cases were diagnosed as current cases [19.4‰, 119/(6 550-409)]. A total of 17 221.65 person-years of follow-up were conducted, during which 71 new cases were diagnosed (4.1/1 000 person-years, 71/17 221.65). The incidence density of PTB was 47.7/1 000 person-years, 6.6/1 000 person-years, 1.4/1 000 person-years, and 0.9/1 000 person-years, respectively, in TST strong/IGRA positive, TST moderate positive, TST generally positive, and TST and IGRA negative populations. The difference in PTB incidence density was statistically significant [likelihood ratio test LRT=153.16, P<0.001]. TPT was performed for individuals with strong TST or IGRA positivity, and the protection rate could reach 93% ( HR=0.07, 95% CI: 0.02-0.23). Conclusion:After the outbreak of the school epidemic, individuals with strong TST/IGRA positivity have a higher risk of developing PTB in the future. Targeted implementation of TPT can achieve better protection effects. In addition, the risk of developing PTB in individuals with moderate TST positivity is also worth noting.

Single-incision bariatric surgery, as a significant advancement in minimally invasive surgery, achieves weight loss goals through a single small incision, offering advantages such as minimal trauma, concealed scarring, and rapid postoperative recovery. The single-incision laparoscopic sleeve gastrectomy (SILSG) currently represents the most widely performed single-incision bariatric procedure globally, demonstrating weight loss efficacy and complication rates comparable to traditional multi-incision laparoscopy alongside significantly higher patient satisfaction. However, the clinical adoption of single-incision bariatric surgery still faces technical challenges with relative scarcity in robust clinical research evidence and underdeveloped standardized surgical protocols and training systems. To further establish a specialized training system and expert consensus for single-incision bariatric surgery that aligns with China's national conditions is of great significance for promoting the standardized implementation of SILSG-represented procedures.

Objective:To evaluate the risk of developing pulmonary tuberculosis (PTB) among individuals with latent tuberculosis infection (LTBI) in schools and the protective effect of tuberculosis preventive treatment (TPT).Methods:A retrospective cohort study was conducted to collect data on 15 school outbreaks that occurred in Guangdong Province from 2017 to 2021. Baseline information on tuberculin skin test (TST) or interferon-gamma release test (IGRA) was obtained during contact surveys, as well as baseline information such as TPT. The incidence of PTB between 2017 and 2022 was queried using the Chinese Center for Disease Control and Prevention Information System. Poisson regression analysis was used to compare the incidence risk of PTB in the LTBI population under different TST states at baseline. Current cases, new cases and all cases (the sum of the two) were used as dependent variables. Cox regression models were used to analyze various risk factors affecting the risk of PTB in the LTBI population and evaluate the protective effect of TPT.Results:A total of 6 550 contacts were included in this study, of which 409 received TPT. Within 0-3 months after baseline survey, 119 cases were diagnosed as current cases [19.4‰, 119/(6 550-409)]. A total of 17 221.65 person-years of follow-up were conducted, during which 71 new cases were diagnosed (4.1/1 000 person-years, 71/17 221.65). The incidence density of PTB was 47.7/1 000 person-years, 6.6/1 000 person-years, 1.4/1 000 person-years, and 0.9/1 000 person-years, respectively, in TST strong/IGRA positive, TST moderate positive, TST generally positive, and TST and IGRA negative populations. The difference in PTB incidence density was statistically significant [likelihood ratio test LRT=153.16, P<0.001]. TPT was performed for individuals with strong TST or IGRA positivity, and the protection rate could reach 93% ( HR=0.07, 95% CI: 0.02-0.23). Conclusion:After the outbreak of the school epidemic, individuals with strong TST/IGRA positivity have a higher risk of developing PTB in the future. Targeted implementation of TPT can achieve better protection effects. In addition, the risk of developing PTB in individuals with moderate TST positivity is also worth noting.

Objective: To evaluate the role of tuberculin skin test prified protein derivative (PPD) in defining the screening scope of close contacts of tuberculosis cases in disposal of tuberculosis outbreak in schools. Methods: In a senior middle school in August 2019, 1 553 students of the grade two were tested by PPD because of a school tuberculosis outbreak. PPD results were compared to grade one students without any association with this tuberculosis epidemic, who were also tested by PPD when beginning school. Potential association between PPD distribution characteristics and tuberculosis case distribution were analyzed. Results: Twenty nine grade two students were diagnozed as tuberculosis infection, seven of which were PPD positive, and with the same MIRU-VNTR genotype. In grade one, 0.1 % (1/796) student showed strong PPD positive, 34.3% (273/796) student showed positive. For grade two students, significant higher rate of strong PPD positive [5.9% (45/757)], and PPD positive [52.0% (394/757)] were observed ( χ 2=45.71, 49.90, P <0.01). Proportion of strong PPD positive in the first floor of the teaching building ( 19.4 %), where tuberculosis cases clustered, was significantly higher than that in other floors ( χ 2=89.81, P <0.01); Number of strong PPD positive students increased with TB cases in each floor of the teaching building ( r =0.99, P <0.01). Proportion of strong PPD positive and PPD positive in floors of the dormitory, where TB cases lived, was significantly higher than in other floors ( χ 2=49.4, 64.9 , P <0.01). Number of strong PPD positive and PPD positive students increased with TB cases in each floor of the teaching building ( r =0.84, 0.56, P <0.01). Conclusion Strong PPD positive rate well reflects tuberculosis infection of close contacts, and is recommended for defining the scope of screening.