Diagnostic accuracy and safety of electromagnetic navigation transthoracic needle biopsy under moderate sedation for the diagnosis of peripheral pulmonary lesions.

Background: Novel approaches using virtual computed tomography (CT) guidance, namely electromagnetic navigation transthoracic needle biopsy (EMN-TTNB), enable physicians to perform percutaneous lung biopsies. However, there are very few studies on the clinical experiences of EMN-TTNB, and in previous studies, the procedure was usually performed under deep sedation. This study aimed to determine the diagnostic accuracy and safety of EMN-TTNB under moderate sedation. Methods: We conducted a retrospective analysis of patients who underwent EMN-TTNB under moderate sedation between May 2021 and November 2022 at Hallym University Dongtan Sacred Heart Hospital in South Korea. Moderate sedation was achieved with midazolam injection in the bronchoscopy room using the Veran SPiNperc EM guidance system (Veran Medical, St Louis, MO, USA). Clinical data were collected by review of medical records, and diagnostic accuracy and safety were calculated. Results: Thirty-two patients were enrolled (mean age 70.8±11.1 years); 56.3% were male. The mean size of the pulmonary lesions was 36.9±17.4 mm, and the median (interquartile range) distance from the pleura was 15.5 (0.0-30.0) mm. The diagnostic accuracy of EMN-TTNB was 75.0% (21/28), excluding four indeterminate cases. Fourteen patients (50.0%, 14/28) had true-positive and seven patients (25.0%, 7/28) had true-negative lesions. There were no severe adverse reactions such as pneumothorax, respiratory failure, or death, except one case of hemoptysis. Conclusions: EMN-TTNB under moderate sedation showed an acceptable diagnostic accuracy and good safety profile. The new technology allows physicians to perform percutaneous lung biopsies without the intervention of a radiologist or anesthesiologist.

The Impact of Air Pollution, Including Asian Sand Dust, on Respiratory Symptoms and Health-related Quality of Life in Outpatients With Chronic Respiratory Disease in Korea: A Panel Study.

OBJECTIVES: Air pollution is a growing concern in Korea because of transboundary air pollution from mainland China. A panel study was conducted to clarify the effects of air pollution on respiratory symptoms and health-related quality of life (HR-QoL) in outpatients with and without chronic obstructive pulmonary disease (COPD) in Korea. METHODS: Patients filled out a questionnaire including self-reported HR-QoL in February and were followed up in May and July. The study was conducted from 2013 to 2015, with different participants each year. Air quality parameters were applied in a generalized estimating equation as independent variables to predict factors affecting HR-QoL. RESULTS: Lower physical fitness scores were associated with Asian sand dust events. Daily activity scores were worse when there were high concentrations of particulate matter (PM) less than 10 µm in diameter (PM10). Lower social functioning scores were associated with high PM less than 2.5 µm in diameter and nitrogen dioxide (NO2) concentrations. High NO2 concentrations also showed a significant association with mental health scores. Weather-related cough was prevalent when PM10, NO2, or ozone (O3) concentrations were high, regardless of COPD severity. High PM10 concentrations were associated with worsened wheezing, particularly in COPD patients. CONCLUSIONS: The results suggest that PM, NO2, and O3 cause respiratory symptoms leading to HR-QoL deterioration. While some adverse effects of air pollution appeared to occur regardless of COPD, others occurred more often and more intensely in COPD patients. The public sector, therefore, needs to consider tailoring air pollution countermeasures to people with different conditions to minimize adverse health effects.

Urinary excretion of 9α,11ß-prostaglandin F2 and leukotriene E4 in patients with exercise-induced bronchoconstriction.

BACKGROUND: Increased levels of mast cell-derived eicosanoids, such as prostaglandin (PG) D2 and cysteinyl leukotrienes (CysLTs), have been reported in patients with exercise-induced bronchoconstriction (EIB), suggesting that mast cell activation is involved in the mechanism of EIB. However, it is still controversial since these results have not been reproduced in other studies. The aim of this study was to evaluate the role of PGD2 and LTE4 in adult asthma with EIB, as measuring urinary levels of their metabolites-9α,11ß-PGF2 and LTE4 before and after an exercise challenge test. METHODS: Eight patients with asthma and EIB and five normal controls without EIB were enrolled. Exercise challenge tests comprised of 6 min of treadmill exercise or free running were performed in all study subjects, and urine samples before and 1 h after the challenge were collected. Urinary levels of 9α,11ß-PGF2 and LTE4 were measured by enzyme immunoassay (EIA). RESULTS: No significant differences were observed in 9α,11ß-PGF2 and LTE4 levels before/after the exercise challenge between patients with EIB and normal controls. No significant increases in urinary levels of 9α,11ß-PGF2 or LTE4 were detected during the exercise challenge in patients with EIB and normal controls. No significant correlations were observed between the percent decrease in forced expiratory volume in 1 s (FEV1) or percent changes in 9α,11ß-PGF2 and LTE4 levels after the exercise challenge. CONCLUSIONS: Urinary 9α,11ß-PGF2 and LTE4 levels did not increase after an exercise challenge in patients with EIB, suggesting that urinary excretion of 9α,11ß-PGF2 and LTE4 may not be a good marker of mast cell activation in patients with EIB.

The association between airflow obstruction and radiologic change by tuberculosis.

INTRODUCTION: Cigarette smoking is the most commonly encountered risk factor for chronic obstructive pulmonary disease (COPD). However, it is not the only one and there is consistent evidence from epidemiologic studies that nonsmokers may develop chronic airflow limitation. A history of tuberculosis has recently been found to be associated with airflow obstruction in adults older than 40 years. The aim of this study was to evaluate the association between the radiologic changes by tuberculosis and airflow obstruction in a population based sample. METHODS: A nationwide COPD prevalence survey was conducted. We compared the prevalence of airflow obstruction according to the presence of the radiologic change by the tuberculosis. RESULTS: We analyzed 1,384 subjects who participated in the nationwide Korean COPD survey. All subjects were older than 40 years and took the spirometry and simple chest radiography. We defined the airflow obstruction as FEV1/FVC <0.7. A total of 149 (10.8%) subjects showed airflow obstruction. A total of 167 (12.1%) subjects showed radiologic change by tuberculosis. Among these 167 subjects, 44 (26.3%) had airflow obstruction. For the subjects without radiologic change by tuberculosis, the prevalence of airflow obstruction was only 8.6%. The unadjusted odds ratio for airflow obstruction according to the radiologic change was 3.788 (95% CI: 2.544-5.642). CONCLUSIONS: The radiologic change by tuberculosis was associated with airflow obstruction.

COPD patients with exertional desaturation are at a higher risk of rapid decline in lung function.

PURPOSE: A recent study demonstrated that exertional desaturation is a predictor of rapid decline in lung function in patients with chronic obstructive pulmonary disease (COPD); however, the study was limited by its method used to detect exertional desaturation. The main purpose of this study was to explore whether exertional desaturation assessed using nadir oxygen saturation (SpO2) during the 6-minute walk test (6MWT) can predict rapid lung function decline in patients with COPD. MATERIALS AND METHODS: A retrospective analysis was performed on 57 patients with moderate to very severe COPD who underwent the 6MWT. Exertional desaturation was defined as a nadir SpO2 of <90% during the 6MWT. Rapid decline was defined as an annual rate of decline in forced expiratory volume in 1 second (FEV1)≥50 mL. Patients were divided into rapid decliner (n=26) and non-rapid decliner (n=31) groups. RESULTS: A statistically significant difference in exertional desaturation was observed between rapid decliners and non-rapid decliners (17 vs. 8, p=0.003). No differences were found between the groups for age, smoking status, BODE index, and FEV1. Multivariate analysis showed that exertional desaturation was a significant independent predictor of rapid decline in patients with COPD (relative risk, 6.8; 95% CI, 1.8 to 25.4; p=0.004). CONCLUSION: This study supports that exertional desaturation is a predictor of rapid lung function decline in male patients with COPD.

Interferon-γ Enzyme-Linked Immunospot Assay in Patients with Tuberculosis and Healthy Adults.

BACKGROUND: Interferon-γ assays based on tuberculosis (TB)-specific antigens have been utilized for diagnosing and ruling out latent TB and active TB, but their utility is still limited for TB incidence countries. The aim of this study is to understand the clinical utility of enzyme-linked immunospot (ELISpot) assays among patients with clinically suspected TB and healthy adults in clinical practices and community-based settings. METHODS: The ELISpot assays (T SPOT.TB, Oxford Immunotec, UK) were prospectively performed in 202 patients. After excluding those with indeterminate results, 196 were included for analysis: 41 were TB patients, 93 were non-TB patients, and 62 were healthy adults. RESULTS: The sensitivity and negative predictive values of the T SPOT.TB assays for the diagnosis of TB were 87.8% and 89.1%, respectively, among patients with suspected TB. The agreement between the tuberculin skin test (10-mm cutoff) and the T SPOT.TB assay was 66.1% (kappa=0.335) in all participants and 80.0% (kappa=0.412) in TB patients. Among those without TB (n=155), a past history of TB and fibrotic TB scar on chest X-rays were significant factors that yielded positive T SPOT.TB results. There was a significant difference in the magnitude of T SPOT.TB spot counts between TB patients and non-TB patients or healthy adults. CONCLUSION: The T SPOT.TB assay appeared to be a useful test for the diagnostic exclusion of TB. A positive result, however, should be cautiously interpreted for potential positives among those without active TB in intermediate TB incidence areas.

Association between pet ownership and the sensitization to pet allergens in adults with various allergic diseases.

PURPOSE: As pet ownership increases, sensitization to animal allergens due to domestic exposure is a concern. Sensitization to animal allergens may occur from indirect exposure, as well as direct ownership of animals. However, there have been conflicting results regarding the association between pet ownership and sensitization to animal allergens in adults. METHODS: In total, 401 patients with various allergic diseases were enrolled in this study. We performed skin prick tests with 55 common inhalant and food allergens, including dog, cat, and rabbit allergens. A mean wheal diameter of 3 mm or greater was considered a positive reaction. The exposure modality to each animal allergen was investigated using a questionnaire and included present ownership, past ownership, occupational exposure, occasional exposure, contact with pet owner, and no contact. Present ownership, past ownership, occupational, and occasional exposure were regarded as direct exposure. RESULTS: The sensitization rate for animal allergens was 20.4% for dog, 15.0% for cat, and 9.0% for rabbit. Direct exposure to dogs (72.0%) was significantly higher than that of other animals (18.4% for cats and 16.7% for rabbits), whereas 'no contact' with cats (78.3%) and rabbits (83.3%) was significantly higher than with dogs (26.8%; P<0.0001). Independent risk factors for sensitization to animal allergens were sensitization to Dermatophagoides pteronyssinus (OR=2.4, P=0.052), Dermatophagoides farinae (OR=5.1, P<0.001), cat (OR=4.4, P<0.0001), and direct exposure to dogs (OR=1.5, P=0.029) for dog, and sensitization to dog (OR=4.4, P<0.0001) and rabbit (OR=2.6, P=0.036) for cats. Finally, for rabbits, the independent risk factor was sensitization to Alternaria (OR=6.0, P<0.002). CONCLUSIONS: These results suggest that direct exposure to dogs contributes to the sensitization to dog allergens in patients with allergic diseases, whereas indirect exposure to cats and rabbits may induce sensitization to each animal's allergen.

Bronchoscopic ethanolamine injection therapy in patients with persistent air leak from chest tube drainage.

BACKGROUND: Chest tube drainage (CTD) is an indication for the treatment of pneumothorax, hemothroax and is used after a thoracic surgery. But, in the case of incomplete lung expansion, and/or persistent air leak from CTD, medical or surgical thoracoscopy or, if that is unavailable, limited thoracotomy, should be considered. We evaluate the efficacy of bronchoscopic injection of ethanolamine to control the persistent air leak in patients with CTD. METHODS: Patients who had persistent or prolonged air leak from CTD were included, consecutively. We directly injected 1.0 mL solution of 5% ethanolamine oleate into a subsegmental or its distal bronchus, where it is a probable air leakage site, 1 to 21 times using an injection needle through a fiberoptic bronchoscope. RESULTS: A total of 15 patients were enrolled; 14 cases of spontaneous pneumothorax [idiopathic 9, chronic obstructive pulmonary disease (COPD) 3, post-tuberculosis 2] and one case of empyema associated with broncho-pleural fistula. Of these, five were patients with persistent air leak from CTD, just after a surgical therapy, wedge resection with plication for blebs or bullae. With an ethanolamine injection therapy, 12 were successful but three (idiopathic, COPD and post-tuberculosis) failed, and were followed by a surgery (2 cases) or pleurodesis (1 case). Some adverse reactions, such as fever, chest pain and increased radiographic opacities occurred transiently, but resolved without any further events. With success, the time from the procedure to discharge was about 3 days (median). CONCLUSION: Bronchoscopic ethanolamine injection therapy may be partially useful in controlling air leakage, and reducing the hospital stay in patients with persistent air leak from CTD.

Application of a new spirometric reference equation and its impact on the staging of Korean chronic obstructive pulmonary disease patients.

PURPOSE: A new spirometric reference equation was recently developed from the first national chronic obstructive pulmonary disease (COPD) survey in Korea. However, Morris' equation has been preferred for evaluating spirometric values instead. The objective of this study was to evaluate changes in severity staging in Korean COPD patients by adopting the newly developed Korean equation. MATERIALS AND METHODS: We evaluated the spirometric data of 441 COPD patients. The presence of airflow limitation was defined as an observed post-bronchodilator forced expiratory volume in one second/forced vital capacity (FEV1/FVC) less than 0.7, and the severity of airflow limitation was assessed according to GOLD stages. Spirometric values were reassessed using the new Korean equation, Morris' equation and other reference equations. RESULTS: The severity of airflow limitation was differently graded in 143 (32.4%) patients after application of the new Korean equation when compared with Morris' equation. All 143 patients were reallocated into more severe stages (49 at mild stage, 65 at moderate stage, and 29 at severe stage were changed to moderate, severe and very severe stages, respectively). Stages according to other reference equations were changed in 18.6-49.4% of the patients. CONCLUSION: These results indicate that equations from different ethnic groups do not sufficiently reflect the airflow limitation of Korean COPD patients. The Korean reference equation should be used for Korean COPD patients in order to administer proper treatment.

Clinical efficacy of direct DNA sequencing analysis on sputum specimens for early detection of drug-resistant Mycobacterium tuberculosis in a clinical setting.

BACKGROUND: Early detection of drug-resistant Mycobacterium tuberculosis is important for the control and prevention of disease transmission. However, conventional drug susceptibility tests for drug-resistant M tuberculosis take at least 3 to 8 weeks. Here, we report the clinical efficacy of direct DNA sequencing analysis for detecting drug-resistant TB on sputum specimens in a clinical setting. METHODS: A total of 113 sputum specimens from 111 patients, who were suspected of having drug-resistant TB by clinicians, were used for DNA sequencing of katG, rpoB, embB, and pncA genes for isoniazid (INH), rifampin (RIF), ethambutol (EMB), and pyrazinamide (PZA) resistance, respectively, and the results were compared with drug susceptibility tests. The optimization of antituberculosis drugs according to the results of DNA sequencing and the treatment outcomes of the patients were also analyzed. RESULTS: Turnaround time of the direct DNA sequencing analysis was 3.8 +/- 1.8 days. We found mutations related to drug resistance in 30 clinical specimens for katG, 39 for rpoB, 13 for embB, and 24 for pncA. The sensitivity and specificity of the assay were 63.6% and 94.6% for INH, 96.2 and 93.9% for RIF, 69.2% and 97.5% for EMB, and 100% and 92.6% for PZA, respectively. Of the patients with RIF resistance, including multidrug-resistant TB by the assay, 92.5% of the patients with initial first-line antituberculosis drugs were changed to second-line antituberculosis drugs, and treatment was successful in 61.9% of these cases. CONCLUSION: Direct DNA sequencing analysis of clinical sputum specimens is a rapid and useful method for the detection and treatment of drug-resistant TB.

Comparison of the prevalence of chronic obstructive pulmonary disease diagnosed by lower limit of normal and fixed ratio criteria.

The Global Initiative of Chronic Obstructive Lung Disease (GOLD) guidelines define chronic obstructive pulmonary disease (COPD) in subjects with FEV(1)/FVC <0.7. However, the use of this fixed ratio may result in over-diagnosis of COPD in the elderly, especially with mild degree of COPD. The lower limit of normal (LLN) can be used to minimize the potential misclassification. The aim of this study was to evaluate the impact of different definitions of airflow obstruction (LLN or fixed ratio of FEV(1)/FVC) on the estimated prevalence of COPD in a population-based sample. We compared the prevalence of COPD and its difference diagnosed by different methods using either fixed ratio (FEV(1)/FVC <0.7) or LLN criterion (FEV(1)/FVC below LLN). Among the 4,816 subjects who had performed spirometry, 2,728 subjects met new ATS/ERS spirometry criteria for acceptability and repeatability. The prevalence of COPD was 10.9% (14.7% in men, 7.2% in women) by LLN criterion and 15.5% (21.8% in men, 9.1% in women) by fixed ratio of FEV(1)/FVC among subjects older than 45 yr. The difference of prevalence between LLN and fixed ratio of FEV(1)/FVC was even higher among subjects with age >/=65, 14.9% and 31.1%, respectively. In conclusion, the prevalence of COPD by LLN criterion was significantly lower in elderly compared to fixed ratio of FEV(1)/FVC. Implementing LLN criterion instead of fixed ratio of FEV(1)/FVC may reduce the risk of over-diagnosis of COPD in elderly people.