BackgroundThis study was aimed to investigate the diagnostic value of fiberoptic bronchoscopy (FOB) with chest high-resolution computed tomography (HRCT) for the rapid diagnosis of active pulmonary tuberculosis (PTB) in patients suspected of PTB but found to have a negative sputum acid-fast bacilli (AFB) smear.MethodsWe evaluated the diagnostic accuracy of results from FOB and HRCT in 126 patients at Gangnam Severance Hospital (Seoul, Korea) who were suspected of having PTB.ResultsOf 126 patients who had negative sputum AFB smears but were suspected of having PTB, 54 patients were confirmed as having active PTB. Hemoptysis was negatively correlated with active PTB. Tree-in-bud appearance on HRCT was significantly associated with active PTB. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FOB alone was 75.9%, 97.2%, 95.3%, and 84.3%, respectively, for the rapid diagnosis of active PTB. The combination of FOB and HRCT improved the sensitivity to 96.3% and the NPV to 96.2%.ConclusionsFOB is a useful tool in the rapid diagnosis of active PTB with a high sensitivity, specificity, PPV and NPV in sputum smear-negative PTB-suspected patients. HRCT improves the sensitivity of FOB when used in combination with FOB in sputum smear-negative patients suspected of having PTB.

The purposes of this study were to evaluate the right ventricular (RV) volume and mass using cardiac multidetector computed tomography (MDCT) and to compare the cardiac MDCT results with those from first-pass radionuclide angiography (FPRA). Twenty patients were evaluated for the RV end-diastolic volume (RVEDV), the RV end-systolic volume (RVESV), the RV ejection fraction (RVEF), and RV mass using cardiac MDCT with a two-phase reconstruction method based on ECG. The end-diastolic phase was reconstructed at the starting point of the QRS complex on ECG, and the end-systolic phase was reconstructed at the halfway point of the ascending T-wave on ECG. The RV mass was measured for the end-systole. The RVEF was also obtained by FPRA. The mean RVEF (47+/-7%) measured by cardiac MDCT was well correlated with that (44+/-6%) measured by FPRA (r=0.854). A significant difference in the mean RVEF was found between cardiac MDCT and FPRA (p=0.001), with an overestimation of 2.9+/-5.3% by cardiac MDCT versus FPRA. The interobserver variability was 4.4% for the RVEDV, 6.8% for the RVESV, and 7.9% for the RV mass, respectively. Cardiac MDCT is relatively simple and allows the RV volume and mass to be assessed, and the RVEF obtained by cardiac MDCT correlates well with that measured by FPRA.

BackgroundVitamin C, as an antioxidant, has recently been suggested to provide protection against COPD; however, only few national cohort studies have investigated these effects. We aimed to confirm the protective effects of vitamin C against COPD in Korean patients.Patients and methodsWe analyzed the data of 3,283 adults aged ≥40 years (representing 23,541,704 subjects) who underwent pulmonary function tests and responded to questionnaires on smoking history and vitamin C intake, with stratification variables and sampling weight designated by the Korea 2012 National Health and Nutrition Examination Survey.ResultsAmong all the subjects, 512 (representing 3,459,679 subjects; 15.6%) were diagnosed as having COPD based on pulmonary function test results. Male gender, old age, residence in suburban/rural regions, low household income, low educational level, an occupation in agriculture or fisheries, and heavy smoking were significantly associated with COPD. Low intake of nutrients, including potassium, vitamin A, carotene, retinol, and vitamin C, was significantly associated with COPD. The prevalence of COPD in heavy smokers with the lowest quartile (Q1, <48.50 mg; 63.0%) and low-middle quartile (Q2, 48.50−84.38 mg; 56.4%) of vitamin C intake was significantly higher than that in subjects with the high-middle quartile (Q3, 84.38−141.63 mg; 29.5%) and highest quartile (Q4, >141.63 mg; 32.6%) of vitamin C intake (P=0.015). In multivariate analysis, male gender, old age, heavy smoking, and a low intake of vitamin C were significant independent risk factors for COPD. A significant reduction of 76.7% in COPD risk was observed with a Q3 vitamin C intake compared to Q1 vitamin C intake (odds ratio, 0.233; 95% confidence interval, 0.094−0.576) in heavy smokers.ConclusionThis large-scale national study suggests that dietary vitamin C provides protection against COPD, independent of smoking history, in the general Korean population.

In this study, we examined the repeatability of computed tomography (CT) lung volume measurements in healthy individuals and patients with obstructive and restrictive lung diseases. To do this, we retrospectively enrolled 200 healthy individuals (group 1), 100 patients with obstructive lung disease (group 2), and 100 patients with restrictive lung disease (group 3) who underwent two consecutive chest CT scans within a 1-year period. The CT lung volume was measured using a threshold-based, three-dimensional auto-segmentation technique at a default range from –200 to –1024 HU. The within-subject standard deviation, repeatability coefficient, within-subject coefficient variability, and intraclass correlation coefficient were evaluated. No significant differences were identified between the two consecutive CT lung volume measurements in any of the groups (p> 0.05). The within-subject standard deviations for groups 1, 2, and 3 were 441.1, 387.0, and 288.6, respectively, while the repeatability coefficients were 1222.6, 1072.6, and 800.1, respectively. The within-subject coefficient variabilities for groups 1, 2, and 3 were 0.097, 0.083, and 0.090, respectively, while the intraclass correlation coefficients were 0.818, 0.881, and 0.910, respectively. The two CT lung volume measurements showed excellent agreement in healthy individuals and patients with obstructive or restrictive lung disease. However, the repeatability was lower in healthy individuals than it was in patients with lung diseases.