Association between oxygen saturation level during bronchoscopy and post-bronchoscopy adverse events: a retrospective cohort study.

Background: Flexible bronchoscopy is widely used to diagnose and treat various respiratory diseases. However, caution is warranted for post-bronchoscopy adverse events. Although desaturation frequently occurs during bronchoscopy, its clinical impact and the optimal oxygen saturation level during the procedure remain unclear.

The Impact of Erosive Reflux Esophagitis on the Decline of Lung Function in the General Population.

Background: The impact of reflux esophagitis on the decline of lung function has been rarely reported. This study was performed to evaluate the association between erosive reflux esophagitis and lung function changes.

Methods: We included patients with normal lung function who underwent esophagogastroduodenoscopy for health screening from a health screening center.

A Genome-Wide Association Study in Early COPD: Identification of One Major Susceptibility Loci.

Background: Identifying the genetic basis of airflow limitation is one of the most interesting issues for understanding chronic obstructive pulmonary disease (COPD) pathophysiology. Several studies have shown that some genetic variants associated with COPD have been identified in genome-wide association study (GWAS), especially in patients with moderate to severe COPD; genetic susceptibility for airflow limitation in the early COPD phase has not been widely studied.

Objective: We investigated the genetic variants in early COPD.

Clinical implication and risk factor of pneumonia development in mild coronavirus disease 2019 patients.

Background/aims: Although a majority of coronavirus disease 2019 (COVID-19) cases were characterized as mild, data assessing the development of pneumonia in mild COVID-19 patients are limited. We aimed to examine the effect of pneumonia development on the clinical course of mild COVID-19 in hospitalized patients.

Methods: A retrospective cohort study was conducted via medical record review between February 25, 2020 and April 11, 2020 at a single center.

Chest computed tomography scan as an initial diagnostic method for tuberculosis infection detected by mass screening.

Background/aims: We assessed the diagnostic yield of chest computed tomography (CT) as an initial diagnostic method for patients with a tuberculosis (TB) infection detected by mass screening in a country with an intermediate TB burden.

Methods: A retrospective study was conducted on patients with TB infection detected by mass screening performed between January 2015 and March 2018. The patients were classified according to whether they had a chest X-ray (CXR) or CT scan as an initial diagnostic test to exclude active TB.

Interstitial Lung Abnormalities and the Clinical Course in Patients With COPD.

Background: The presence and progression of interstitial lung abnormalities (ILAs) is known to be associated with a decline of lung function and increased risk of mortality.

Research Question: We aimed to elucidate the clinical course according to ILAs in patients with COPD.

Study Design And Methods: A retrospective study was conducted between January 2013 and December 2018 of COPD patients who underwent chest CT imaging and longitudinal pulmonary function tests.

The clinical impact of drug-induced hepatotoxicity on anti-tuberculosis therapy: a case control study.

Background: There are limited data available on whether drug-induced hepatotoxicity (DIH) affects the clinical outcomes of tuberculosis (TB) treatment. We explored the effects of DIH on the clinical course and outcomes of pulmonary TB.

Methods: In this retrospective cohort study, we included patients with culture-proven pulmonary TB treated in a tertiary hospital from 2013 to 2016.

Thromboembolism in Infection: Analysis and Literature Review.

Background: Tuberculosis is associated with hypercoagulation; however, there are few reports of cases thromboembolism and tuberculosis at the same time in the real world. The purpose of this study was to report the incidence and clinical course of thromboembolism in patients diagnosed with tuberculosis.

Materials And Methods: We retrospectively analyzed the data of patients who were diagnosed with both tuberculosis and thromboembolism including pulmonary thromboembolism (PTE) or deep vein thrombosis (DVT) at Seoul National University Boramae Medical Center from January 2000 through March 2015.

Long-Term Follow-Up of Ground-Glass Nodules After 5 Years of Stability.

Introduction: Small ground-glass nodules (GGNs) or those with an indeterminate risk on low-dose computed tomography (LDCT) of the chest are recommended at 5-year follow-up, but the rationale for follow-up beyond 5 years is unclear.

Methods: An observational study was conducted to investigate the natural course of GGNs that had been stable for 5 years by LDCT over 10 years. All eligible GGNs were detected during regular health checkups.

Comparison of clinical characteristics and outcomes between homeless and non-homeless patients admitted to intensive care units: An observational propensity-matched cohort study in Korea.

Purpose: To compare clinical characteristics and outcomes between critically ill homeless and non-homeless patients admitted to the intensive care unit (ICU) in a Korea.

Materials And Methods: We retrospectively analyzed the medical charts of homeless and non-homeless patients admitted to ICU at Seoul Boramae Medical Center between January 2012 and December 2017. Patients were selected using 1: 2 propensity score matching including age, sex, and type of ICU and multivariate analyses were performed to determine risk factors for hospital and ICU mortality.

The effect of metformin on culture conversion in tuberculosis patients with diabetes mellitus.

Background/aims: Patients with diabetes mellitus (DM) and tuberculosis (TB) have increased morbidity and a high risk of treatment failure or recurrence. It is important to manage both diseases simultaneously. Among anti-diabetic drugs, metformin inhibits intracellular growth of mycobacteria.

Risk factors for pulmonary arterial hypertension in patients with tuberculosis-destroyed lungs and their clinical characteristics compared with patients with chronic obstructive pulmonary disease.

Background And Objective: There are limited data on pulmonary arterial hypertension (PAH) in patients with tuberculosis-destroyed lung (TDL), a sequela of pulmonary tuberculosis. We identified the risk factors for PAH and their effects on acute exacerbation and mortality in patients with TDL, as well as the clinical differences in patients with chronic obstructive pulmonary disease (COPD) and PAH.

Methods: A retrospective cohort study was conducted from 2010 through 2015 in a municipal referral hospital in South Korea.

Effect of Prophylactic Use of Silymarin on Anti-tuberculosis Drugs Induced Hepatotoxicity.

Background: The first line of anti-tuberculosis (TB) drugs are the most effective standard of drugs for TB. However, the use of these drugs is associated with hepatotoxicity. Silymarin has protective effects against hepatotoxicity of anti-TB drugs in animal models.

Chronic obstructive pulmonary disease is independently associated with hypertension in men: A survey design analysis using nationwide survey data.

Although studies have shown that chronic obstructive pulmonary disease (COPD) and hypertension are linked as comorbidities, it remains unclear whether COPD is independently associated with the risk of hypertension or is caused by common risk factors such as age and smoking. The objective of this study was to investigate the relationship between COPD and hypertension by using nationally representative data.This cross-sectional study analyzed data from the Korea National Health and Nutrition Examination Survey V conducted during 2010 to 2012.

The effect of obesity on patients with mild chronic obstructive pulmonary disease: results from KNHANES 2010 to 2012.

Purpose: A low body mass index has been associated with high mortalities in patients with chronic obstructive pulmonary disease (COPD), and studies reveal that obesity aggravates the clinical effects of COPD. We investigated the impact of obesity on patients newly identified with COPD.

Patients And Methods: This population-based, cross-sectional study, used data from the Korea National Health and Nutrition Examination Survey (KNHANES) conducted from 2010 to 2012.

Prediction of Anthracofibrosis Based on Clinico-Radiographic Findings.

Purpose: Because anthracofibrosis (AF) is associated with tuberculosis (TB), detection of AF is clinically relevant in Korea, a TB endemic region. We thus sought to develop and validate a predictive model for AF using clinical radiographic data.

Materials And Methods: Between January 1, 2008 and March 31, 2014, 3849 adult patients who underwent bronchoscopies were retrospectively included from an observational registry.

The regional association between bronchiectasis and lung cancer in chest CT.

Background: Limited studies have examined the association between lung cancer and bronchiectasis (BE). This study evaluated the regional association between BE and lung cancer by analyzing the lobar location of lung cancer in patients with underlying BE.

Methods: This clustered multi-level study enrolled patients who had underlying BE and were newly diagnosed with lung cancer between January 1, 2010 and May 30, 2013 in two referral hospitals in South Korea.

Discordance between MTB/RIF and Real-Time Tuberculosis-Specific Polymerase Chain Reaction Assay in Bronchial Washing Specimen and Its Clinical Implications.

The prevalence and clinical implications of discordance between Xpert MTB/RIF assays and the AdvanSure TB/NTM real-time polymerase chain reaction (PCR) for bronchial washing specimens have not been studied in pulmonary TB (PTB) patients. The discordant proportion and its clinical impact were evaluated in 320 patients from the bronchoscopy registry whose bronchial washing specimens were tested simultaneously with Xpert MTB/RIF and the TB/NTM PCR assay for three years, and the accuracy of the assays, including the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), were studied. The clinical risk factors for discordance and false positivity of assays were also studied.

The association of renin-angiotensin system blockades and pneumonia requiring admission in patients with COPD.

Background: The hallmark of COPD is chronic airway inflammation, which may be mediated by renin-angiotensin system. The renin-angiotensin system blockers such as angiotensin-converting enzyme inhibitors (ACEi) and angiotensin II receptor blockers (ARBs) have exhibited anti-inflammatory and immunomodulatory effects in patients with various diseases. We explored the effects of ACEi and ARBs on the risk of pneumonia in patients with COPD.

Association between Helicobacter pylori seropositivity and mild to moderate COPD: clinical implications in an Asian country with a high prevalence of H. pylori.

Background: Helicobacter pylori infection is a major cause of gastric diseases. The clinical implications of H. pylori infection in various diseases outside the gastrointestinal system have also been reported, including in some respiratory disorders.

Effect of perioperative systemic steroid treatment on patients with obstructive lung disease undergoing elective abdominal surgery.

Introduction: Chronic obstructive pulmonary disease is an independent risk factor of postoperative pulmonary complications (PPCs). It is unknown whether a perioperative systemic corticosteroid would be beneficial in patients with obstructive airway disease.

Objectives: The present study was conducted to determine the effect of a perioperative systemic corticosteroid on PPCs in patients who showed airway obstruction in preoperative spirometry.

The effect of using blood culture bottle of bronchoalveolar larvage fluid in pneumonia.

Background: Pneumonia is a primary cause of morbidity and mortality in infectious disease, and increasing antimicrobial resistance has raised concerns of treatment failure. Therefore, we evaluated the value of a blood culture bottle for bronchoalveolar lavage (BAL) samples on pathogen identification and on treatment modification in patients with pneumonia.

Methods: We conducted a prospective study and enrolled 39 patients who were hospitalized for pneumonia.

Association of incidental emphysema with annual lung function decline and future development of airflow limitation.

Objectives: Emphysema is one of the prognostic factors for rapid lung function decline in patients with COPD, but the impact of incidentally detected emphysema on population without spirometric abnormalities has not been evaluated. This study aimed to determine whether emphysema detected upon computed tomography (CT) screening would accelerate the rate of lung function decline and influence the possibility of future development of airflow limitation in a population without spirometric abnormalities.

Materials And Methods: Subjects who participated in a routine screening for health checkup and follow-up pulmonary function tests for at least 3 years between 2004 and 2010 were retrospectively enrolled.

The Association of BCG Vaccination with Atopy and Asthma in Adults.

Introduction: There are few studies investigating the association between BCG vaccination and atopy or asthma in adults.

Objective: We investigated the association between BCG scar and the occurrence of atopy and asthma in Korean adults.

Methods: We carried out a retrospective study of Korean adults who underwent skin prick testing, and, in some cases, spirometry and bronchial provocation tests in a secondary care hospital from April 2010 to February 2011.