Mycobacterium tuberculosis Infection in School Contacts of Tuberculosis Cases: A Systematic Review and Meta-Analysis.

Substantial tuberculosis transmission occurs outside of households, and tuberculosis surveillance in schools has recently been proposed. However, the yield of tuberculosis outcomes from school contacts is not well characterized. We assessed the prevalence of Mycobacterium tuberculosis infection among close school contacts by performing a systematic review. We searched PubMed, Elsevier, China National Knowledge Infrastructure, and Wanfang databases. Studies reporting the number of children who were tested overall and who tested positive were included. Subgroup analyses were performed by study location, index case bacteriological status, type of school, and other relevant factors. In total, 28 studies including 54,707 school contacts screened for M. tuberculosis infection were eligible and included in the analysis. Overall, the prevalence of M. tuberculosis infection determined by the QuantiFERON Gold in-tube test was 33.2% (95% CI, 0.0-73.0%). The prevalences of M. tuberculosis infection based on the tuberculin skin test (TST) using 5 mm, 10 mm, and 15 mm as cutoffs were 27.2% (95% CI, 15.1-39.3%), 24.3% (95% CI, 15.3-33.4%), and 12.7% (95% CI, 6.3-19.0%), respectively. The pooled prevalence of M. tuberculosis infection (using a TST ≥5-mm cutoff) was lower in studies from China (22.8%; 95% CI, 16.8-28.8%) than other regions (36.7%; 95% CI, 18.1-55.2%). The pooled prevalence of M. tuberculosis infection was higher when the index was bacteriologically positive (43.6% [95% CI, 16.5-70.8%] versus 23.8% [95% CI, 16.2-31.4%]). These results suggest that contact investigation and general surveillance in schools from high-burden settings merit consideration as means to improve early case detection in children.

Effect of Temperature-Dependent Low Oxygen Partial Pressure Annealing on SiC MOS.

Oxygen post annealing is a promising method for improving the quality of the SiC metal oxide semiconductor (MOS) interface without the introduction of foreign atoms. In addition, a low oxygen partial pressure annealing atmosphere would prevent the additional oxidation of SiC, inhibiting the generation of new defects. This work focuses on the effect and mechanism of low oxygen partial pressure annealing at different temperatures (900-1250 °C) in the SiO2/SiC stack. N2 was used as a protective gas to achieve the low oxygen partial pressure annealing atmosphere. X-ray photoelectron spectroscopy (XPS) characterization was carried out to confirm that there are no N atoms at or near the interface. Based on the reduction in interface trap density (Dit) and border trap density (Nbt), low oxygen partial pressure annealing is proven to be an effective method in improving the interface quality. Vacuum annealing results and time of flight secondary ion mass spectrometry (ToF-SIMS) results reveal that the oxygen vacancy (V[O]) filling near the interface is the dominant annealing mechanism. The V[O] near the interface is filled more by O2 in the annealing atmosphere with the increase in temperature.

Yield and Efficiency of a Population-Based Mass Tuberculosis Screening Intervention Among Persons With Diabetes in Jiangsu Province, China.

BACKGROUND: The evidence-base for mass tuberculosis screening among persons with diabetes (PWD) is poor. We evaluated the yield and costs of mass screening among PWD in eastern China. METHODS: We included individuals with type 2 diabetes from 38 townships in Jiangsu Province. Screening comprised of physical examinations, symptom screening, and chest X-rays; smear and culture testing were performed through clinical triage. We assessed the yield and number needed to screen (NNS) to detect 1 tuberculosis case among all PWD, those with symptoms, and with suggestive chest X-rays. Unit costing was collected to estimate screening costs and to calculate cost per case detected. We performed a systematic review of other mass tuberculosis screening programs concentrated on PWD. RESULTS: Of 89 549 screened PWD, 160 were diagnosed with tuberculosis (179 cases per 100 000 persons; 95% confidence interval [CI]: 153-205). The NNS was 560 (95% CI: 513-606), 248 (95% CI: 217-279), and 36 (95% CI: 24-48) among all participants, with abnormal chest X-rays, and symptoms. The cost per case was high overall (US$13 930) but lower with symptoms (US$1037) and high fasting blood glucose levels (US$6807). From systematic review, the pooled NNS to detect one case among all PWD (regardless of symptoms or chest X-ray results) in high- versus low-burden settings was 93 (95% CI: 70-141) versus 395 (95% CI: 283-649). CONCLUSIONS: A mass tuberculosis screening program focused on PWD was feasible however, the overall yield was low and not cost-efficient. Risk-stratified approaches may be practical among PWD in low- and medium tuberculosis burden settings.

A risk score for prediction of poor treatment outcomes among tuberculosis patients with diagnosed diabetes mellitus from eastern China.

Persons living with diabetes (PLWD) with newly diagnosed tuberculosis are at greater risk of poor treatment outcomes. Identifying and prioritizing high-risk subgroups of PLWD and tuberculosis for tuberculosis programs to target has been rarely performed. We investigated risk factors for poor tuberculosis treatment outcomes among PLWD and developed a predictive risk score for tuberculosis control prioritization. Among PLWD diagnosed with tuberculosis, demographic, clinical, and tuberculosis treatment outcome data were collected. Poor treatment outcomes included treatment failure, death, default, and transfer. Multivariable logistic regression modeling was used to analyze risk factors of poor treatment outcomes. Risk scores were derived based on regression coefficients to classify participants at low-, intermediate-, and high-risk of poor treatment outcomes. Among 335 PLWD newly diagnosed with tuberculosis, 109 were cured and 172 completed treatment. Multivariable logistic regression found that risk factors of poor treatment outcomes included bacteriologically-positivity, low body mass index, no physical activity, and pulmonary cavitation. Rates of poor treatment outcomes in low- (0-2), intermediate- (3-4), and high-risk (5-8) groups were 4.2%, 10.5%, and 55.4% (Ptrend < 0.0001), respectively. The risk score accurately discriminated poor and successful treatment outcomes (C-statistic, 0.85, 95% CI 0.78-0.91). We derived a simple predictive risk score that accurately distinguished those at high- and low-risk of treatment failure. This score provides a potentially useful tool for tuberculosis control programs in settings with a double burden of both tuberculosis and diabetes.

Glycemic Trajectories and Treatment Outcomes of Patients with Newly Diagnosed Tuberculosis: A Prospective Study in Eastern China.

Rationale: Patients with newly diagnosed tuberculosis often have inconsistent glycemic measurements during and after treatment. Distinct glycemic trajectories after the diagnosis of tuberculosis are not well characterized, and whether patients with stress hyperglycemia have poor treatment outcomes is not known.Objectives: To identify distinct glycemic trajectories from the point of tuberculosis diagnosis to the posttreatment period and to assess the relationship between glycemic trajectories and tuberculosis treatment outcomes.Methods: Patients with newly diagnosed, drug-susceptible tuberculosis and with at least three fasting plasma glucose tests at tuberculosis diagnosis and during the third and sixth month of treatment were identified and included from Jiangsu Province, China. Patients were also given an additional fasting plasma glucose test at 2 and 4 months after treatment.Measurements and Main Results: Several distinct glycemic trajectories from the point of tuberculosis diagnosis to the posttreatment period were found, including consistently normal glycemic testing results (43%), transient hyperglycemia (24%), erratic glycemic instability (12%), diabetes (16%), and consistent hyperglycemia without diabetes (6%). Compared with participants with a consistently normal glycemic trajectory, patients with transient hyperglycemia were more likely to experience treatment failure (adjusted odds ratio [AOR], 4.20; 95% confidence interval [CI], 1.57-11.25; P = 0.004) or erratic glycemic instability (AOR, 5.98; 95% CI, 2.00-17.87; P = 0.001). Patients living with diabetes also had a higher risk of experiencing treatment failure (AOR, 6.56; 95% CI, 2.22-19.35; P = 0.001), and this was modified by glycemic control and metformin use.Conclusions: Among patients with tuberculosis without diabetes, glycemic changes were common and may represent an important marker for patient response to tuberculosis treatment.