When is LABA/LAMA Better than LAMA in GOLD Group B or D Patients for Reducing Acute Exacerbations of COPD? / 전남의대학술지

Long-acting  2 -agonist (LABA)/long-acting muscarinic-antagonist (LAMA) dual therapy has been found to be more effective than LAMA monotherapy in the treatment of chronic obstructive pulmonary disease (COPD). However, among patients with group B or D COPD, the characteristics of patients for whom LABA/LAMA dual therapy is superior to LAMA monotherapy in minimizing acute exacerbations remain unknown.With data from a prospective COPD cohort, subgroup analyses were conducted to determine whether LABA/LAMA dual therapy was superior to LAMA monotherapy in reducing the rate of acute exacerbations in group B and D COPD patients. Group B and D COPD patients taking LAMA or LABA/LAMA were enrolled according to the 2022 Global initiative for Chronic Obstructive Pulmonary Disease guidelines. A total of 737 patients were included in this study: 600 with group B COPD and 137 with group D COPD. Compared with patients taking LAMA monotherapy, those taking LABA/ LAMA had a significantly lower incidence of acute exacerbations over 1 year. In the subgroup of patients ≥70 years old, there was a significantly lower risk of severe COPD exacerbations among group B patients taking LABA/LAMA than among those taking LAMA monotherapy (odds ratio [OR], 0.258; 95% confidence interval [CI], 0.095– 0.703). In contrast, in the subgroup of group D patients with COPD Assessment Test scores ≥25, compared with LAMA monotherapy, LABA/LAMA treatment was associated with lower risk of severe COPD exacerbations (OR, 0.115; 95% CI, 0.018-0.749).The combination of LABA and LAMA was found to be superior to LAMA monotherapy, especially for treating older adults with group B COPD, as well as for group D patients with severe symptoms.

Radial Probe Endobronchial Ultrasound Using Guide Sheath-Guided Transbronchial Lung Biopsy in Peripheral Pulmonary Lesions without Fluoroscopy / 결핵및호흡기질환

Background@#Radial probe endobronchial ultrasound-guided transbronchial lung biopsy (RP-EBUS-TBLB) has improved the diagnostic yield of bronchoscopic biopsy of peripheral pulmonary lesions (PPLs). The diagnostic yield and complications of RP-EBUS-TBLB for PPLs vary depending on the technique, such as using a guide sheath (GS) or fluoroscopy. In this study, we investigated the utility of RP-EBUS-TBLB using a GS without fluoroscopy for diagnosing PPLs. @*Methods@#We retrospectively reviewed data from 607 patients who underwent RP-EBUS of PPLs from January 2019 to July 2020. TBLB was performed using RP-EBUS with a GS without fluoroscopy. The diagnostic yield and complications were assessed. Multivariable logistic regression analyses were used to identify factors affecting the diagnostic yields. @*Results@#The overall diagnostic accuracy was 76.1% (462/607). In multivariable analyses, the size of the lesion (≥20 mm; odds ratio [OR], 2.06; 95% confidence interval [CI], 1.27–3.33; p=0.003), positive bronchus sign in chest computed tomography (OR, 2.30; 95% CI, 1.40–3.78; p=0.001), a solid lesion (OR, 2.40; 95% CI, 1.31–4.41; p=0.005), and an EBUS image with the probe within the lesion (OR, 6.98; 95% CI, 4.38–11.12; p<0.001) were associated with diagnostic success. Pneumothorax occurred in 2.0% (12/607) of cases and chest tube insertion was required in 0.5% (3/607) of patients. @*Conclusion@#RP-EBUS-TBLB using a GS without fluoroscopy is a highly accurate diagnostic method in diagnosing PPLs that does not involve radiation exposure and has acceptable complication rates.

Experience of Treating Critically Ill COVID-19 Patients in Daegu, South Korea / 결핵및호흡기질환

At the beginning of February 2020, Daegu faced a serious situation due to the rapid outbreak of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus-2. The healthcare system in Daegu Metropolitan City was ill-prepared for this sudden disaster situation. The COVID-19 pandemic is still ongoing in South Korea. Daegu has limited medical resources compared to the Seoul Metropolitan Area, and it is hypothesized that a review of the outbreak therein could provide information that will be valuable for dealing with future outbreaks. The likelihood of death due to COVID-19 depends on the capacity of the area for the treatment of critically ill patients. This report reviews the overall treatment process followed for critically ill patients in Daegu.

SARS-CoV-2 Omicron Mutation Is Faster than the Chase: Multiple Mutations on Spike/ACE2 Interaction Residues

Recently, a new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (B.1.1.529) Omicron variant originated from South Africa in the middle of November 2021. SARS-CoV-2 is also called coronavirus disease 2019 (COVID-19) since SARS-CoV-2 is the causative agent of COVID-19. Several studies already suggested that the SARS-CoV-2 Omicron variant would be the fastest transmissible variant compared to the previous 10 SARS-CoV-2 variants of concern, interest, and alert. Few clinical studies reported the high transmissibility of the Omicron variant but there is insufficient time to perform actual experiments to prove it, since the spread is so fast. We analyzed the SARS-CoV-2 Omicron variant, which revealed a very high rate of mutation at amino acid residues that interact with angiostatin-converting enzyme 2. The mutation rate of COVID-19 is faster than what we prepared vaccine program, antibody therapy, lockdown, and quarantine against COVID-19 so far. Thus, it is necessary to find better strategies to overcome the current crisis of COVID-19 pandemic.

Utility of Radial Probe Endobronchial Ultrasound Guided Transbronchial Lung Biopsy in Bronchus Sign Negative Peripheral Pulmonary Lesions

Background@#The presence of the bronchus sign on chest computed tomography is associated with an increased diagnostic yield of radial probe endobronchial ultrasound– guided transbronchial lung biopsy (RP-EBUS-TBLB). However, the utility of RP-EBUS-TBLB for bronchus sign negative peripheral pulmonary lesions (PPLs) remains unknown. We investigated the utility of RP-EBUS-TBLB in bronchus sign negative PPLs. @*Methods@#We retrospectively reviewed data from 109 patients who underwent RP-EBUS for bronchus sign negative PPLs from January 2019 to August 2020. TBLB was performed using RP-EBUS with a guide sheath and without fluoroscopy. The EBUS visualization and TBLB diagnostic yields were assessed. Multivariable logistic regression analyses were used to identify factors affecting the EBUS visualization and diagnostic yields. @*Results@#The EBUS visualization yield was 74.1% (68/109). Of the 109 lung lesions, 92 were definitively diagnosed. The overall diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 50.5% (55/109), 34.9% (29/83), 100% (26/26), 100% (29/29), and 32.5% (26/80), respectively. In multivariable analyses, the size of the lesion (≥ 20 mm; odds ratio [OR], 2.62; 95% confidence interval [CI], 1.16–5.93; P = 0.021) and the distance from the pleura (> 10 mm; OR, 2.37; 95% CI, 1.02–5.52; P = 0.045) were associated with EBUS visualization. Regarding diagnostic yield, having the probe within the lesion (OR, 28.50; 95% CI, 6.26–129.85; P < 0.001) and a solid lesion (OR, 14.58; 95% CI, 2.64–80.38; P = 0.002) were associated with diagnostic success. Pneumothorax and hemoptysis occurred in 3.7% (4/109) and 0.9% (1/109), respectively, of the patients. @*Conclusion@#RP-EBUS-TBLB using a GS can be considered a diagnostic method in bronchus sign negative solid PPLs. Having the probe within the lesion and a solid lesion were important for diagnostic success. Complication rates were acceptable.

Quantitative Assessment of Chest CT Patterns in COVID-19 and Bacterial Pneumonia Patients: a Deep Learning Perspective

Background@#It is difficult to distinguish subtle differences shown in computed tomography (CT) images of coronavirus disease 2019 (COVID-19) and bacterial pneumonia patients, which often leads to an inaccurate diagnosis. It is desirable to design and evaluate interpretable feature extraction techniques to describe the patient's condition. @*Methods@#This is a retrospective cohort study of 170 confirmed patients with COVID-19 or bacterial pneumonia acquired at Yeungnam University Hospital in Daegu, Korea. The lung and lesion regions were segmented to crop the lesion into 2D patches to train a classifier model that could differentiate between COVID-19 and bacterial pneumonia. The K-means algorithm was used to cluster deep features extracted by the trained model into 20 groups.Each lesion patch cluster was described by a characteristic imaging term for comparison.For each CT image containing multiple lesions, a histogram of lesion types was constructed using the cluster information. Finally, a Support Vector Machine classifier was trained with the histogram and radiomics features to distinguish diseases and severity. @*Results@#The 20 clusters constructed from 170 patients were reviewed based on common radiographic appearance types. Two clusters showed typical findings of COVID-19, with two other clusters showing typical findings related to bacterial pneumonia. Notably, there is one cluster that showed bilateral diffuse ground-glass opacities (GGOs) in the central and peripheral lungs and was considered to be a key factor for severity classification. The proposed method achieved an accuracy of 91.2% for classifying COVID-19 and bacterial pneumonia patients with 95% reported for severity classification. The CT quantitative parameters represented by the values of cluster 8 were correlated with existing laboratory data and clinical parameters. @*Conclusion@#Deep chest CT analysis with constructed lesion clusters revealed well-known COVID-19 CT manifestations comparable to manual CT analysis. The constructed histogram features improved accuracy for both diseases and severity classification, and showedcorrelations with laboratory data and clinical parameters. The constructed histogram features can provide guidance for improved analysis and treatment of COVID-19.

Radial Probe Endobronchial Ultrasound Using Guide Sheath-Guided Transbronchial Lung Biopsy in Peripheral Pulmonary Lesions without Fluoroscopy / 결핵및호흡기질환

Background@#Radial probe endobronchial ultrasound-guided transbronchial lung biopsy (RP-EBUS-TBLB) has improved the diagnostic yield of bronchoscopic biopsy of peripheral pulmonary lesions (PPLs). The diagnostic yield and complications of RP-EBUS-TBLB for PPLs vary depending on the technique, such as using a guide sheath (GS) or fluoroscopy. In this study, we investigated the utility of RP-EBUS-TBLB using a GS without fluoroscopy for diagnosing PPLs. @*Methods@#We retrospectively reviewed data from 607 patients who underwent RP-EBUS of PPLs from January 2019 to July 2020. TBLB was performed using RP-EBUS with a GS without fluoroscopy. The diagnostic yield and complications were assessed. Multivariable logistic regression analyses were used to identify factors affecting the diagnostic yields. @*Results@#The overall diagnostic accuracy was 76.1% (462/607). In multivariable analyses, the size of the lesion (≥20 mm; odds ratio [OR], 2.06; 95% confidence interval [CI], 1.27–3.33; p=0.003), positive bronchus sign in chest computed tomography (OR, 2.30; 95% CI, 1.40–3.78; p=0.001), a solid lesion (OR, 2.40; 95% CI, 1.31–4.41; p=0.005), and an EBUS image with the probe within the lesion (OR, 6.98; 95% CI, 4.38–11.12; p<0.001) were associated with diagnostic success. Pneumothorax occurred in 2.0% (12/607) of cases and chest tube insertion was required in 0.5% (3/607) of patients. @*Conclusion@#RP-EBUS-TBLB using a GS without fluoroscopy is a highly accurate diagnostic method in diagnosing PPLs that does not involve radiation exposure and has acceptable complication rates.

Experience of Treating Critically Ill COVID-19 Patients in Daegu, South Korea / 결핵및호흡기질환

At the beginning of February 2020, Daegu faced a serious situation due to the rapid outbreak of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus-2. The healthcare system in Daegu Metropolitan City was ill-prepared for this sudden disaster situation. The COVID-19 pandemic is still ongoing in South Korea. Daegu has limited medical resources compared to the Seoul Metropolitan Area, and it is hypothesized that a review of the outbreak therein could provide information that will be valuable for dealing with future outbreaks. The likelihood of death due to COVID-19 depends on the capacity of the area for the treatment of critically ill patients. This report reviews the overall treatment process followed for critically ill patients in Daegu.

Utility of Radial Probe Endobronchial Ultrasound Guided Transbronchial Lung Biopsy in Bronchus Sign Negative Peripheral Pulmonary Lesions

Background@#The presence of the bronchus sign on chest computed tomography is associated with an increased diagnostic yield of radial probe endobronchial ultrasound– guided transbronchial lung biopsy (RP-EBUS-TBLB). However, the utility of RP-EBUS-TBLB for bronchus sign negative peripheral pulmonary lesions (PPLs) remains unknown. We investigated the utility of RP-EBUS-TBLB in bronchus sign negative PPLs. @*Methods@#We retrospectively reviewed data from 109 patients who underwent RP-EBUS for bronchus sign negative PPLs from January 2019 to August 2020. TBLB was performed using RP-EBUS with a guide sheath and without fluoroscopy. The EBUS visualization and TBLB diagnostic yields were assessed. Multivariable logistic regression analyses were used to identify factors affecting the EBUS visualization and diagnostic yields. @*Results@#The EBUS visualization yield was 74.1% (68/109). Of the 109 lung lesions, 92 were definitively diagnosed. The overall diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 50.5% (55/109), 34.9% (29/83), 100% (26/26), 100% (29/29), and 32.5% (26/80), respectively. In multivariable analyses, the size of the lesion (≥ 20 mm; odds ratio [OR], 2.62; 95% confidence interval [CI], 1.16–5.93; P = 0.021) and the distance from the pleura (> 10 mm; OR, 2.37; 95% CI, 1.02–5.52; P = 0.045) were associated with EBUS visualization. Regarding diagnostic yield, having the probe within the lesion (OR, 28.50; 95% CI, 6.26–129.85; P < 0.001) and a solid lesion (OR, 14.58; 95% CI, 2.64–80.38; P = 0.002) were associated with diagnostic success. Pneumothorax and hemoptysis occurred in 3.7% (4/109) and 0.9% (1/109), respectively, of the patients. @*Conclusion@#RP-EBUS-TBLB using a GS can be considered a diagnostic method in bronchus sign negative solid PPLs. Having the probe within the lesion and a solid lesion were important for diagnostic success. Complication rates were acceptable.

Quantitative Assessment of Chest CT Patterns in COVID-19 and Bacterial Pneumonia Patients: a Deep Learning Perspective

Background@#It is difficult to distinguish subtle differences shown in computed tomography (CT) images of coronavirus disease 2019 (COVID-19) and bacterial pneumonia patients, which often leads to an inaccurate diagnosis. It is desirable to design and evaluate interpretable feature extraction techniques to describe the patient's condition. @*Methods@#This is a retrospective cohort study of 170 confirmed patients with COVID-19 or bacterial pneumonia acquired at Yeungnam University Hospital in Daegu, Korea. The lung and lesion regions were segmented to crop the lesion into 2D patches to train a classifier model that could differentiate between COVID-19 and bacterial pneumonia. The K-means algorithm was used to cluster deep features extracted by the trained model into 20 groups.Each lesion patch cluster was described by a characteristic imaging term for comparison.For each CT image containing multiple lesions, a histogram of lesion types was constructed using the cluster information. Finally, a Support Vector Machine classifier was trained with the histogram and radiomics features to distinguish diseases and severity. @*Results@#The 20 clusters constructed from 170 patients were reviewed based on common radiographic appearance types. Two clusters showed typical findings of COVID-19, with two other clusters showing typical findings related to bacterial pneumonia. Notably, there is one cluster that showed bilateral diffuse ground-glass opacities (GGOs) in the central and peripheral lungs and was considered to be a key factor for severity classification. The proposed method achieved an accuracy of 91.2% for classifying COVID-19 and bacterial pneumonia patients with 95% reported for severity classification. The CT quantitative parameters represented by the values of cluster 8 were correlated with existing laboratory data and clinical parameters. @*Conclusion@#Deep chest CT analysis with constructed lesion clusters revealed well-known COVID-19 CT manifestations comparable to manual CT analysis. The constructed histogram features improved accuracy for both diseases and severity classification, and showedcorrelations with laboratory data and clinical parameters. The constructed histogram features can provide guidance for improved analysis and treatment of COVID-19.

Clinical Characteristics and Changes of Clinical Features in Patients with Asthma-COPD Overlap in Korea according to Different Diagnostic Criteria / 결핵및호흡기질환

Background@#Asthma–chronic obstructive pulmonary disease (COPD) overlap (ACO) is a condition characterized by the overlapping clinical features of asthma and COPD. To evaluate the appropriateness of different sets of ACO definition, we compared the clinical characteristics of the previously defined diagnostic criteria and the specialist opinion in this study. @*Methods@#Patients enrolled in the KOrea COpd Subgroup Study (KOCOSS) were evaluated. Based on the questionnaire data, the patients were categorized into the ACO and non-ACO COPD groups according to the four sets of the diagnostic criteria. @*Results@#In total 1,475 patients evaluated: 202 of 1,475 (13.6%), 32 of 1,475 (2.2%), 178 of 1,113 (16.0%), and 305 of 1,250 (24.4%) were categorized as ACO according to the modified Spanish Society of Pneumonology and Thoracic Surgery (SEPAR), American Thoracic Society (ATS) Roundtable, Global Initiative for Asthma (GINA)/Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria, and the specialists diagnosis, respectively. The ACO group defined according to the GINA/GOLD criteria showed significantly higher St. George's Respiratory Questionnaire and COPD Assessment Test scores than the non-ACO COPD group. When the modified SEPAR definition was applied, the ACO group showed a significantly larger decrease in the forced expiratory volume in 1 second (FEV1, %). The ACO group defined by the ATS Roundtable showed significantly larger decrease in the forced vital capacity values compared to the non-ACO COPD group (–18.9% vs. –2.2%, p=0.007 and –412 mL vs. –17 mL, p=0.036). The ACO group diagnosed by the specialists showed a significantly larger decrease in the FEV1 (%) compared to the non-ACO group (–5.4% vs. –0.2%, p=0.003). @*Conclusion@#In this study, the prevalence and clinical characteristics of ACO varied depending on the diagnostic criteria applied. With the criteria which are relatively easy to use, defining ACO by the specialists diagnosis may be more practical in clinical applications.

Clinical Features and Outcomes of 98 PatientsHospitalized with SARS-CoV-2 Infection in Daegu,South Korea: A Brief Descriptive Study

Although some information on the epidemiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and a few selectedcases has been reported, data on the clinical characteristics and outcomes of patients hospitalized therewith in South Koreaare lacking. We conducted a retrospective single-center study of 98 consecutive hospitalized patients with confirmed SARS-CoV-2infection at Yeungnam University Medical Center in Daegu, South Korea. Sixty patients were women (61.2%), and the mean agewas 55.4±17.1 years. Thirteen patients (13.3%) were treated in the intensive care unit (ICU). The mean interval from symptom onsetto hospitalization was 7.7±4.5 days. Patients who received ICU care were significantly older and were more likely to have diabetesmellitus. The National Early Warning Score on the day of admission was significantly higher in patients requiring ICU care. Acuterespiratory distress syndrome (13/13 patients; 100%), septic shock (9/13; 69.2%), acute cardiac injury (9/13; 69.2%), and acute kidneyinjury (8/13; 61.5%) were more common in patients who received ICU care. All patients received antibiotic therapy, and most(97/98 patients; 99.0%) received antiviral therapy (lopinavir/ritonavir). Hydroxychloroquine was used in 79 patients (80.6%), andglucocorticoid therapy was used in 18 patients (18.4%). In complete blood counts, lymphopenia was the most common finding(40/98 patients; 40.8%). Levels of all proinflammatory cytokines were significantly higher in ICU patients. As of March 29, 2020, themortality rate was 5.1%. Here, we report the clinical characteristics and laboratory findings of SARS-CoV-2 patients in South Koreaup to March 29, 2020.

The Risk of Diabetes on Clinical Outcomes in Patients with Coronavirus Disease 2019: A Retrospective Cohort Study

Background@#To determine the role of diabetes mellitus (DM) in the coronavirus disease 2019 (COVID-19), we explored the clinical characteristics of patients with DM and compared risk factors such as age, glycemic control, and medications to those without DM. @*Methods@#This was a retrospective cohort study of 117 confirmed patients with COVID-19 which conducted at a tertiary hospital in Daegu, South Korea. The primary outcome was defined as the severe and critical outcome (SCO), of which the composite outcomes of acute respiratory distress syndrome, septic shock, intensive care unit care, and 28-day mortality. We analyzed what clinical features and glycemic control-related factors affect the prognosis of COVID-19 in the DM group. @*Results@#After exclusion, 110 participants were finally included. DM patients (n=29) was older, and showed higher blood pressure compared to non-DM patients. DM group showed higher levels of inflammation-related biomarkers and severity score, and highly progressed to SCO. After adjustment with other risk factors, DM increased the risk of SCO (odds ratio [OR], 10.771;p <0.001). Among the DM patients, SCO was more prevalent in elderly patients of ≥70 years old and age was an independent risk factor for SCO in patients with DM (OR, 1.175; p =0.014), while glycemic control was not. The use of medication did not affect the SCO, but the renin-angiotensin system inhibitors showed protective effects against acute cardiac injury (OR, 0.048; p=0.045). @*Conclusion@#The COVID-19 patients with DM had higher severity and resulted in SCO. Intensive and aggressive monitoring of COVID-19 clinical outcomes in DM group, especially in elderly patients is warranted.

Clinical Role of the Chronic Obstructive Pulmonary Disease Assessment Test in Prediction of the Response to Treatment for Exacerbations

BACKGROUND@#The chronic obstructive pulmonary disease (COPD) assessment test (CAT) is a validated, eight-item questionnaire used to quantify the health status of patients. The aim of this study was to evaluate the usefulness of the CAT questionnaire as a tool to assess the response to treatment in acute exacerbations of COPD in an outpatient setting.@*METHODS@#A multicenter, phase 3 randomized controlled trial was conducted previously to examine the efficacy and safety of oral zabofloxacin for the treatment of COPD exacerbations. In the present post hoc analysis of the original study, patients with COPD exacerbation were categorized as responders or non-responders according to the respiratory symptoms persisting on day 10 (visit 3) of treatment. The CAT questionnaire was completed daily by patients at home from the initial visit to the second visit on day 5. Subsequently, the questionnaire was completed in the presence of a physician on days 10 (visit 3) and 36 (visit 4). Multivariate regression analysis was performed to determine the association between CAT scores and the therapeutic response.@*RESULTS@#The CAT scores decreased more rapidly in responders compared to non-responders during the first 5 days (23.3–20.4 vs. 23.5–22). Among responders, patients with higher severity of illness also revealed higher CAT scores on the first day of an exacerbation (mild, 19.8; moderate, 21.4; severe, 23.8; very severe, 28.6). Multivariate analysis revealed that a change in the CAT score during the first 3 days influenced the therapeutic response. A significant decrease in scores in the domains of sputum production, chest tightness, and activities of daily living was seen among responders.@*CONCLUSION@#Early improvement in CAT scores may be associated with a more favorable response to the treatment of COPD exacerbations.TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01658020TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0000532

The Progression of SARS Coronavirus 2 (SARS-CoV2): Mutation in the Receptor Binding Domain of Spike Gene

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) is a positive-sense singlestranded RNA (+ssRNA) that causes coronavirus disease 2019 (COVID-19). The viral genome encodes twelve genes for viral replication and infection. The third open reading frame is the spike (S) gene that encodes for the spike glycoprotein interacting with specific cell surface receptor – angiotensin converting enzyme 2 (ACE2) – on the host cell membrane. Most recent studies identified a single point mutation in S gene. A single point mutation in S gene leading to an amino acid substitution at codon 614 from an aspartic acid 614 into glycine (D614G) resulted in greater infectivity compared to the wild type SARS-CoV2. We were interested in investigating the mutation region of S gene of SARS-CoV2 from Korean COVID-19 patients. New mutation sites were found in the critical receptor binding domain (RBD) of S gene, which is adjacent to the aforementioned D614G mutation residue. This specific sequence data demonstrated the active progression of SARS-CoV2 by mutations in the RBD of S gene.The sequence information of new mutations is critical to the development of recombinant SARS-CoV2 spike antigens, which may be required to improve and advance the strategy against a wide range of possible SARS-CoV2 mutations.

Clinical Characteristics and Changes of Clinical Features in Patients with Asthma-COPD Overlap in Korea according to Different Diagnostic Criteria / 결핵및호흡기질환

Background@#Asthma–chronic obstructive pulmonary disease (COPD) overlap (ACO) is a condition characterized by the overlapping clinical features of asthma and COPD. To evaluate the appropriateness of different sets of ACO definition, we compared the clinical characteristics of the previously defined diagnostic criteria and the specialist opinion in this study. @*Methods@#Patients enrolled in the KOrea COpd Subgroup Study (KOCOSS) were evaluated. Based on the questionnaire data, the patients were categorized into the ACO and non-ACO COPD groups according to the four sets of the diagnostic criteria. @*Results@#In total 1,475 patients evaluated: 202 of 1,475 (13.6%), 32 of 1,475 (2.2%), 178 of 1,113 (16.0%), and 305 of 1,250 (24.4%) were categorized as ACO according to the modified Spanish Society of Pneumonology and Thoracic Surgery (SEPAR), American Thoracic Society (ATS) Roundtable, Global Initiative for Asthma (GINA)/Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria, and the specialists diagnosis, respectively. The ACO group defined according to the GINA/GOLD criteria showed significantly higher St. George's Respiratory Questionnaire and COPD Assessment Test scores than the non-ACO COPD group. When the modified SEPAR definition was applied, the ACO group showed a significantly larger decrease in the forced expiratory volume in 1 second (FEV1, %). The ACO group defined by the ATS Roundtable showed significantly larger decrease in the forced vital capacity values compared to the non-ACO COPD group (–18.9% vs. –2.2%, p=0.007 and –412 mL vs. –17 mL, p=0.036). The ACO group diagnosed by the specialists showed a significantly larger decrease in the FEV1 (%) compared to the non-ACO group (–5.4% vs. –0.2%, p=0.003). @*Conclusion@#In this study, the prevalence and clinical characteristics of ACO varied depending on the diagnostic criteria applied. With the criteria which are relatively easy to use, defining ACO by the specialists diagnosis may be more practical in clinical applications.

Clinical Role of the Chronic Obstructive Pulmonary Disease Assessment Test in Prediction of the Response to Treatment for Exacerbations

BACKGROUND@#The chronic obstructive pulmonary disease (COPD) assessment test (CAT) is a validated, eight-item questionnaire used to quantify the health status of patients. The aim of this study was to evaluate the usefulness of the CAT questionnaire as a tool to assess the response to treatment in acute exacerbations of COPD in an outpatient setting.@*METHODS@#A multicenter, phase 3 randomized controlled trial was conducted previously to examine the efficacy and safety of oral zabofloxacin for the treatment of COPD exacerbations. In the present post hoc analysis of the original study, patients with COPD exacerbation were categorized as responders or non-responders according to the respiratory symptoms persisting on day 10 (visit 3) of treatment. The CAT questionnaire was completed daily by patients at home from the initial visit to the second visit on day 5. Subsequently, the questionnaire was completed in the presence of a physician on days 10 (visit 3) and 36 (visit 4). Multivariate regression analysis was performed to determine the association between CAT scores and the therapeutic response.@*RESULTS@#The CAT scores decreased more rapidly in responders compared to non-responders during the first 5 days (23.3–20.4 vs. 23.5–22). Among responders, patients with higher severity of illness also revealed higher CAT scores on the first day of an exacerbation (mild, 19.8; moderate, 21.4; severe, 23.8; very severe, 28.6). Multivariate analysis revealed that a change in the CAT score during the first 3 days influenced the therapeutic response. A significant decrease in scores in the domains of sputum production, chest tightness, and activities of daily living was seen among responders.@*CONCLUSION@#Early improvement in CAT scores may be associated with a more favorable response to the treatment of COPD exacerbations.TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01658020TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0000532

The Progression of SARS Coronavirus 2 (SARS-CoV2): Mutation in the Receptor Binding Domain of Spike Gene

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) is a positive-sense singlestranded RNA (+ssRNA) that causes coronavirus disease 2019 (COVID-19). The viral genome encodes twelve genes for viral replication and infection. The third open reading frame is the spike (S) gene that encodes for the spike glycoprotein interacting with specific cell surface receptor – angiotensin converting enzyme 2 (ACE2) – on the host cell membrane. Most recent studies identified a single point mutation in S gene. A single point mutation in S gene leading to an amino acid substitution at codon 614 from an aspartic acid 614 into glycine (D614G) resulted in greater infectivity compared to the wild type SARS-CoV2. We were interested in investigating the mutation region of S gene of SARS-CoV2 from Korean COVID-19 patients. New mutation sites were found in the critical receptor binding domain (RBD) of S gene, which is adjacent to the aforementioned D614G mutation residue. This specific sequence data demonstrated the active progression of SARS-CoV2 by mutations in the RBD of S gene.The sequence information of new mutations is critical to the development of recombinant SARS-CoV2 spike antigens, which may be required to improve and advance the strategy against a wide range of possible SARS-CoV2 mutations.

Clinical Role of the Chronic Obstructive Pulmonary Disease Assessment Test in Prediction of the Response to Treatment for Exacerbations

Validation of Previous Spirometric Reference Equations and New Equations