Timely Pulmonary Tuberculosis Diagnosis Based on the Epidemiological Disease Spectrum: Population-Based Prospective Cohort Study in the Republic of Korea.

BACKGROUND: Timely pulmonary tuberculosis (PTB) diagnosis is a global health priority for interrupting transmission and optimizing treatment outcomes. The traditional dichotomous time-divided approach for addressing time delays in diagnosis has limited clinical application because the time delay significantly varies depending on each community in question. OBJECTIVE: We aimed to reevaluate the diagnosis time delay based on the PTB disease spectrum using a novel scoring system that was applied at the national level in the Republic of Korea. METHODS: The Pulmonary Tuberculosis Spectrum Score (PTBSS) was developed based on previously published proposals related to the disease spectrum, and its validity was assessed by examining both all-cause and PTB-related mortality. In our analysis, we integrated the PTBSS into the Korea Tuberculosis Cohort Registry. We evaluated various time delays, including patient, health care, and overall delays, and their system-associated variables in line with each PTBSS. Furthermore, we reclassified the scores into distinct categories of mild (PTBSS=0-1), moderate (PBTBSS=2-3), and severe (PBTBSS=4-6) using a multivariate regression approach. RESULTS: Among the 14,031 Korean patients with active PTB whose data were analyzed from 2018 to 2020, 37% (n=5191), 38% (n=5328), and 25% (n=3512) were classified as having a mild, moderate, and severe disease status, respectively, according to the PTBSS. This classification can therefore reflect the disease spectrum of PTB by considering the correlation of the score with mortality. The time delay patterns differed according to the PTBSS. In health care delays according to the PTBSS, greater PTB disease progression was associated with a shorter diagnosis period, since the condition is microbiologically easy to diagnose. However, with respect to patient delays, the change in elapsed time showed a U-shaped pattern as PTB progressed. This means that a remarkable patient delay in the real-world setting might occur at both apical ends of the spectrum (ie, in both mild and severe cases of PTB). Independent risk factors for a severe PTB pattern were age (adjusted odds ratio 1.014) and male sex (adjusted odds ratio 1.422), whereas no significant risk factor was found for mild PTB. CONCLUSIONS: Timely PTB diagnosis should be accomplished. This can be improved with use of the PTBSS, a simple and intuitive scoring system, which can be more helpful in clinical and public health applications compared to the traditional dichotomous time-only approach.

Effect of complicated, untreated and uncontrolled diabetes and pre-diabetes on treatment outcome among patients with pulmonary tuberculosis.

BACKGROUND AND OBJECTIVE: Patients with tuberculosis and diabetes have a higher risk of unfavourable anti-tuberculosis treatment outcomes. In the present study, we aimed to evaluate the effects of various diabetes statuses on the outcomes of patients with pulmonary tuberculosis. METHODS: Among the patients with pulmonary tuberculosis enrolled in the Korea Tuberculosis Cohort (KTBC) registry and the multicentre prospective cohort study of pulmonary tuberculosis (COSMOTB), those with diabetes and complicated diabetes were identified. The primary and secondary outcomes were unfavourable outcomes and mortality, respectively. The effect of diabetes and complicated diabetes on the outcomes was assessed using multivariable logistic regression analysis. Using COSMOTB, subgroup analyses were performed to assess the association between various diabetes statuses and outcomes. RESULTS: In the KTBC, diabetes (adjusted odds ratio [aOR] = 1.93, 95% CI = 1.64-2.26) and complicated diabetes (aOR = 1.96, 95% CI = 1.67-2.30) were significantly associated with unfavourable outcomes, consistent with the COSMOTB data analysis. Based on subgroup analysis, untreated diabetes at baseline was an independent risk factor for unfavourable outcomes (aOR = 2.72, 95% CI = 1.26-5.61). Prediabetes and uncontrolled diabetes increased unfavourable outcomes and mortality without statistical significance. CONCLUSION: Untreated and complicated diabetes at the time of tuberculosis diagnosis increases the risk of unfavourable outcomes and mortality.

Estimating the prevalence and clinical significance of chronic obstructive pulmonary disease-obstructive sleep apnea overlap in South Korea.

INTRODUCTION: Concurrent obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD) are referred to as COPD-OSA overlap. We investigated the prevalence and clinical significance of COPD-OSA overlap in the general population of South Korea. METHODS: Data were obtained from the 2019 Korea National Health and Nutrition Examination Survey. Participants ≥40 years of age with complete STOP-Bang questionnaire and spirometry data were included. OSA was presumed in individuals with a STOP-Bang score of ≥3. COPD was determined using forced expiratory volume at 1 s/forced vital capacity <0.7. Participants were classified on the basis of the STOP-Bang score and spirometry findings. Clinical characteristics, comorbidities, and quality of life (using the EuroQoL 5-dimension instrument) were compared between the overlap group and COPD-alone or OSA-alone groups. RESULTS: Among the 3157 participants, 6.9 % demonstrated COPD-OSA overlap. Individuals with OSA alone and COPD alone were 31.8 % and 5.2 %, respectively. The overlap group included more males, ever smokers, and frequent alcohol drinkers than the COPD- or OSA-alone groups. The overlap group had more diagnoses of hypertension, diabetes, and stroke than the COPD-alone group. The risk of anxiety/depression was approximately 2.5 times higher in the overlap group than in the COPD-alone group. COPD-OSA overlap was a significant risk factor for anxiety/depression after adjusting for age, sex, household income, and education levels. CONCLUSION: COPD-OSA overlap is not rare within the general population of South Korea. Patients with overlap showed more comorbidities and higher levels of anxiety/depression than those in the COPD-alone group.

Development of the Rapid Cough Questionnaire: Key item identification.

BACKGROUND: The Leicester Cough Questionnaire (LCQ) is a reliable tool for measuring the multidimensional impact of cough on patients' quality of life; however, its scoring algorithm is lengthy and complex for routine clinical use. OBJECTIVE: The study aimed to develop a simplified version of the LCQ, the Rapid Cough Questionnaire (RCQ), as a substitue in clinical practice and validate the RCQ using an independent cohort. METHODS: To select items for the RCQ score, a correlation network was used to determine the items from each domain that were strongly correlated with the total LCQ score. The final items for the RCQ were selected on the basis of the centrality of the node degree, betweenness, and closeness in the correlation network. RESULTS: The RCQ score was derived from 3 items: tiredness (LCQ3) in the physical domain, the feeling of being fed up (LCQ13) in the psychological domain, and annoyance with partner/family/friends (LCQ19) in the social domain. The correlation between the LCQ and RCQ was high, with a coefficient of 0.93 (P < .001). The mean score of the RCQ was 11.2 ± 3.2, with scores ranging from 5.15 to 19.55. The minimal clinically important difference in the RCQ score was calculated to be 1.6 using a distribution-based method. The concurrent validity of the LCQ and the RCQ with cough numeric rating scale was similar. In the validation cohort, the correlation between the LCQ and RCQ scores was consistent regardless of sex and etiology. CONCLUSION: The RCQ score, which is concise, reliable, and valid, can be a valuable tool for patient assessment, particularly in clinical practice.

Characteristics of subclinical tuberculosis compared to active symptomatic tuberculosis using nationwide registry cohort in Korea: prospective cohort study.

Objective: The clinical manifestations of tuberculosis (TB) range from asymptomatic to disseminated depending on the microbiological and immunological status, making the diagnosis challenging. To improve our understanding of the disease progression mechanism, we aimed to identify the characteristics of subclinical TB and important predictors of symptom development. Methods: From July 2018 to June 2019, we systemically collected data from the National Surveillance System of South Korea on patients with pulmonary TB, and compared the characteristics of subclinical and active symptomatic TB patients. Results: A total of 4,636 patients with pulmonary TB were included, and the prevalence of subclinical TB was 37.1% (1,720/4,636). In subclinical TB patients, the positivity rates of acid-fast bacilli (AFB) smear and culture were 16.2 and 50.2%, respectively. Subclinical TB patients were younger (55.6 ± 19.2 vs. 60.7 ± 19.5, P < 0.001), had a higher body mass index (21.7 ± 3.1 vs. 21.0 ± 3.5, P < 0.001), less under Medicaid support, and had lower rates of chronic lung disease, AFB smear and culture positivity, and bilateral disease. Regarding the characteristic differences of individual TB-related symptoms, age was positively associated with dyspnoea and general weakness but negatively associated with chest pain, haemoptysis, and weight loss. Male patients were more prone to weight loss. Chronic lung disease was related to symptoms including cough/phlegm, dyspnoea, and haemoptysis, while autoimmune diseases were associated with fever and weight loss. Conclusions: The development of TB-related symptoms was associated with microbiological burden and clinical characteristics including underlying comorbidities, which should be evaluated carefully.

Risk adjustment model for tuberculosis compared to non-tuberculosis mycobacterium or latent tuberculosis infection: Center for Personalized Precision Medicine of Tuberculosis (cPMTb) cohort database.

BACKGROUND: The Center for Personalized Precision Medicine of Tuberculosis (cPMTb) was constructed to develop personalized pharmacotherapeutic systems for tuberculosis (TB). This study aimed to introduce the cPMTb cohort and compare the distinct characteristics of patients with TB, non-tuberculosis mycobacterium (NTM) infection, or latent TB infection (LTBI). We also determined the prevalence and specific traits of polymorphisms in N-acetyltransferase-2 (NAT2) and solute carrier organic anion transporter family member 1B1 (SLCO1B1) phenotypes using this prospective multinational cohort. METHODS: Until August 2021, 964, 167, and 95 patients with TB, NTM infection, and LTBI, respectively, were included. Clinical, laboratory, and radiographic data were collected. NAT2 and SLCO1B1 phenotypes were classified by genomic DNA analysis. RESULTS: Patients with TB were older, had lower body mass index (BMI), higher diabetes rate, and higher male proportion than patients with LTBI. Patients with NTM infection were older, had lower BMI, lower diabetes rate, higher previous TB history, and higher female proportion than patients with TB. Patients with TB had the lowest albumin levels, and the prevalence of the rapid, intermediate, and slow/ultra-slow acetylator phenotypes were 39.2%, 48.1%, and 12.7%, respectively. The prevalence of rapid, intermediate, and slow/ultra-slow acetylator phenotypes were 42.0%, 44.6%, and 13.3% for NTM infection, and 42.5%, 48.3%, and 9.1% for LTBI, respectively, which did not differ significantly from TB. The prevalence of the normal, intermediate, and lower transporter SLCO1B1 phenotypes in TB, NTM, and LTBI did not differ significantly; 74.9%, 22.7%, and 2.4% in TB; 72.0%, 26.1%, and 1.9% in NTM; and 80.7%, 19.3%, and 0% in LTBI, respectively. CONCLUSIONS: Understanding disease characteristics and identifying pharmacokinetic traits are fundamental steps in optimizing treatment. Further longitudinal data are required for personalized precision medicine. TRIAL REGISTRATION: This study registered ClinicalTrials.gov NO. NCT05280886.

Risk of loss to follow-up among tuberculosis patients in South Korea: whom should we focus on?

Introduction: In South Korea, public-private mix (PPM) has been a key strategy in national tuberculosis (TB) control program. This study aimed to identify rate of loss to follow-up (LTFU) among TB patients in nationwide PPM institutions and their risk factors. Methods: A nationwide prospective observational study including drug susceptible TB patients diagnosed from the 1st day to the 10th day of every month between July 2018 and December 2020 in PPM institutions was designed. Multivariable survival models in which death and failure were designated as events with competing risk were used to investigate risk factors for LTFU. Results: A total of 14,942 patients were included. Of them, 356 (2.4%) had an LTFU. Risk factors for LTFU were: underweight patients (adjusted hazard ratio (aHR): 1.47, 95% CI: 1.12-1.92), patients living alone (aHR: 1.43, 95% CI: 1.16-1.76), heavy drinkers (aHR: 1.67, 95% CI: 1.16-2.39), those with malignancy (aHR: 1.49, 95% CI: 1.07-2.05), foreigners (aHR: 5.96, 95% CI: 4.51-7.89), and those with previous TB history reported as an unfavorable outcome (aHR: 4.43, 95% CI: 2.77-7.08). Effect of age on LTFU was not significant. Brief interruption of anti-TB treatment (less than two months) in current session was associated with subsequent LTFU [adjusted odds ratio: 13.09 (10.29-16.66)]. Conclusion: Identifying vulnerability of patients such as living alone, being heavy alcoholics, being foreigners or having previous TB history reported as an unfavorable outcome is required. Thorough case management for these vulnerable groups could be feasible with collaboration between public and private sectors.

Effects of underweight and overweight on mortality in patients with pulmonary tuberculosis.

Background: Poor nutrition increases disease severity and mortality in patients with tuberculosis (TB). There are gaps in our understanding of the effects of being underweight or overweight on TB in relation to sex. Methods: We generated a nationwide TB registry database and assessed the effects of body mass index (BMI) on mortality in patients with pulmonary TB. The cause of death was further classified as TB-related or non-TB-related deaths. First, logistic regression analysis was performed to assess the association between BMI (a continuous variable) and mortality, and subgroup analyses of the multivariable logistic regression model were performed separately in male and female patients. Second, we categorized BMI into three groups: underweight, normal weight, and overweight, and assessed the impact of being underweight or overweight on mortality with reference to normal weight. Results: Among 9,721 patients with pulmonary TB, the mean BMI was 21.3 ± 3.4; 1,927 (19.8%) were underweight, and 2,829 (29.1%) were overweight. In multivariable logistic regression analysis, mortality was significantly increased with the decrement of BMI (adjusted odds ratio [aOR] = 0.893, 95% confidence interval [CI] = 0.875-0.911). In subgroup analyses, underweight patients had significantly higher odds of mortality, especially TB-related deaths (aOR = 2.057, 95% CI = 1.546-2.735). The association with mortality and male patients was higher (aOR = 2.078, 95% CI = 1.717-2.514), compared with female patients (aOR = 1.724, 95% CI = 1.332-2.231). Being overweight had a significant protective effect against TB-related death only in females (aOR = 0.500, 95% CI = 0.268-0.934), whereas its effect on non-TB-related death was observed only in males (aOR = 0.739, 95% CI = 0.587-0.930). Conclusion: Being underweight was linked to high mortality, whereas being overweight had beneficial effects in patients with pulmonary TB.

Deaths from tuberculosis: differences between tuberculosis-related and non-tuberculosis-related deaths.

Objective: Tuberculosis (TB) is a major cause of ill health and one of the leading causes of death worldwide. The first step in developing strategies to reduce TB mortality is to identify the direct causes of death in patients with TB and the risk factors for each cause. Methods: Data on patients with TB systemically collected from the National Surveillance System of South Korea from January 2019 to December 2020 were included in this study. We analyzed the clinical characteristics associated with TB and non-TB-related deaths, including TB-related symptoms, comorbidities, and radiographic and microbiological findings. Results: Of the total of 12,340 patients with TB, 61% were males with a mean age of 61.3 years. During the follow-up period, the overall mortality rate was 10.6%, with TB-related deaths accounting for 21.3% of all TB deaths. The median survival time in the TB-related death group was 22 days. TB-related death was associated with older age, lower body mass index (BMI), dyspnea, fever, general weakness, bilateral radiographic patterns, and acid-fast bacilli (AFB)-positive smears. Non-TB-related deaths were associated with older age, male sex, lower BMI, comorbidities of heart, liver, kidney, and central nervous system (CNS) diseases, CNS TB involvement, the presence of dyspnea, general weakness, and bilateral radiographic patterns. Conclusion: Patients with high-risk TB must be identified through cause-specific mortality analysis, and the mortality rate must be reduced through intensive monitoring of patients with a high TB burden and comorbidities.

Metabolic Disorders Are Associated With Drug-Induced Liver Injury During Antituberculosis Treatment: A Multicenter Prospective Observational Cohort Study in Korea.

Background: Drug-induced liver injury (DILI) may lead to the discontinuation of antituberculosis (anti-TB) treatment (ATT). Some studies have suggested that metabolic disorders increase the risk of DILI during ATT. This study aimed to identify risk factors for DILI, particularly metabolic disorders, during ATT. Methods: A multicenter prospective observational cohort study to evaluate adverse events during ATT was conducted in Korea from 2019 to 2021. Drug-susceptible patients with TB who had been treated with standard ATT for 6 months were included. The patients were divided into 2 groups depending on the presence of 1 or more metabolic conditions, such as insulin resistance, hypertension, obesity, and dyslipidemia. We monitored ATT-related adverse events, including DILI, and treatment outcomes. The incidence of DILI was compared between individuals with and without metabolic disorders, and related factors were evaluated. Results: Of 684 patients, 52 (7.6%) experienced DILI, and 92.9% of them had metabolic disorders. In the multivariable analyses, underlying metabolic disorders (adjusted hazard ratio [aHR], 2.85; 95% CI, 1.01-8.07) and serum albumin <3.5 g/dL (aHR, 2.26; 95% CI, 1.29-3.96) were risk factors for DILI during ATT. In the 1-month landmark analyses, metabolic disorders were linked to an elevated risk of DILI, especially significant alanine aminotransferase elevation. The treatment outcome was not affected by the presence of metabolic disorders. Conclusions: Patients with metabolic disorders have an increased risk of ATT-induced liver injury compared with controls. The presence of metabolic disorders and hypoalbuminemia adversely affects the liver in patients with ATT.

Cough Characteristics and Their Association Patterns According to Cough Etiology: A Network Analysis.

Although cough is a common respiratory symptom, determining its cause is challenging. We aimed to explore how cough severity and characteristics vary with different etiologies, while investigating their interrelations with demographic features. Adult patients (n = 220) with chronic cough and completed diagnostic work-up and the COugh Assessment Test were enrolled. A correlation network analysis was used to examine the associations between the demographic features and cough severity/characteristics across various etiologies such as upper airway cough syndrome, asthma, eosinophilic bronchitis, gastroesophageal reflux disease (GERD), and idiopathic cough. Demographic features like age and sex showed complex associations with cough characteristics and severity. Cough severity decreased with age, especially in cases of eosinophilic bronchitis and GERD. Women with eosinophilic bronchitis reported more severe cough, while men with idiopathic cough reported more severe cough. Asthma was significantly linked to more sleep disturbance and fatigue, independent of age and sex, whereas GERD showed less sleep disturbance and fatigue. Network analysis revealed overall close associations between cough characteristics, though hypersensitivity in asthma and sleep disturbance in GERD were not linked with other cough traits. In conclusion, the demographic features and cough characteristics were interrelated, exhibiting distinct patterns based on the etiology.

Summary of Korean Asthma Guideline.

Asthma is a chronic inflammatory airway disease that is characterized by variable airflow obstruction. The Korean Asthma Study Group of the Korean Academy of Tuberculosis and Respiratory Diseases has recently updated the Korean Asthma Guideline. This review summarizes the updated Korean Asthma Guideline. Asthma prevalence is increasing worldwide, and in Korea. Variable airflow obstruction can be confirmed by bronchodilator response or other tests, and should be established prior to the controller medication. A low-dose inhaled corticosteroid-formoterol is used to alleviate symptoms in all treatment step, and it can be used as a controller as well as reliever in steps 3-5. This approach is preferred, because it reduces the risk of severe exacerbations, compared to the use of short-acting ß2-agonist as reliever. In severe asthma, phenotype/endotype based on the underlying inflammation should be evaluated. For type 2 severe asthma, the biologics should be considered.

Prediction models for respiratory outcomes in patients with COVID-19: integration of quantitative computed tomography parameters, demographics, and laboratory features.

Background: We aimed to develop integrative machine-learning models using quantitative computed tomography (CT) parameters in addition to initial clinical features to predict the respiratory outcomes of coronavirus disease 2019 (COVID-19). Methods: This was a retrospective study involving 387 patients with COVID-19. Demographic, initial laboratory, and quantitative CT findings were used to develop predictive models of respiratory outcomes. High-attenuation area (HAA) (%) and consolidation (%) were defined as quantified percentages of the area with Hounsfield units between -600 and -250 and between -100 and 0, respectively. Respiratory outcomes were defined as the development of pneumonia, hypoxia, or respiratory failure. Multivariable logistic regression and random forest models were developed for each respiratory outcome. The performance of the logistic regression model was evaluated using the area under the receiver operating characteristic curve (AUC). The accuracy of the developed models was validated by 10-fold cross-validation. Results: A total of 195 (50.4%), 85 (22.0%), and 19 (4.9%) patients developed pneumonia, hypoxia, and respiratory failure, respectively. The mean patient age was 57.8 years, and 194 (50.1%) were female. In the multivariable analysis, vaccination status and levels of lactate dehydrogenase, C-reactive protein (CRP), and fibrinogen were independent predictors of pneumonia. The presence of hypertension, levels of lactate dehydrogenase and CRP, HAA (%), and consolidation (%) were selected as independent variables to predict hypoxia. For respiratory failure, the presence of diabetes, levels of aspartate aminotransferase, and CRP, and HAA (%) were selected. The AUCs of the prediction models for pneumonia, hypoxia, and respiratory failure were 0.904, 0.890, and 0.969, respectively. Using the feature selection in the random forest model, HAA (%) was ranked as one of the top 10 features predicting pneumonia and hypoxia and was first place for respiratory failure. The accuracies of the cross-validation of the random forest models using the top 10 features for pneumonia, hypoxia, and respiratory failure were 0.872, 0.878, and 0.945, respectively. Conclusions: Our prediction models that incorporated quantitative CT parameters into clinical and laboratory variables showed good performance with high accuracy.

Differential effects of sex on tuberculosis location and severity across the lifespan.

Disparities exist between sexes regarding tuberculosis (TB) incidence, as well as disease severity and outcome. Using a nationwide TB registry database, we explored the impact of sex and age on extrapulmonary TB (EPTB) among all enrolled patients by (1) calculating the female proportion for every age category according to TB-affected locations, (2) calculating the proportions of EPTB stratified by sex according to age, (3) conducting multivariable analysis to examine the impact of sex and age on EPTB likelihood, and (4) assessing the odds of EPTB for female compared to male as reference in every age category. Further, we explored the impact of sex and age on disease severity among pulmonary TB (PTB) patients. Of all the TB patients, 40.1% were female, with a male-to-female ratio of 1.49. The proportion of females was lowest in their fifties, resembling a U-shape. The male-to-female ratios in PTB and EPTB were 1.67 and 1.03, respectively. Compared to men, women were significantly associated with EPTB in their forties, fifties, and sixties. Female patients with PTB had significantly lower odds of having cavitation and positive smear test results in their fifties. Significant differences were found concerning TB location and severity between sexes, especially during reproductive age.

Association of rheumatoid arthritis with bronchial asthma and asthma-related comorbidities: A population-based national surveillance study.

Background: The aim of this study was to investigate the impact of rheumatoid arthritis (RA) on the prevalence of bronchial asthma and asthma-related comorbidities. We also aimed to identify the influence of RA on interrelationship between asthma and asthma-related comorbidities. Methods: From the Korean National Health and Nutrition Examination Survey, participants >40 years of age who completed questionnaires and spirometry tests were enrolled. Patient data on RA, asthma, allergic rhinitis, atopic dermatitis, chronic obstructive pulmonary disease (COPD), sinusitis, otitis media, and body mass index (BMI) were collected. Logistic regression and network analyses were performed. Results: A total of 14,272 subjects were enrolled, among which, 334 (2.4%) had RA. RA was significantly associated with asthma (OR 2.32; 95% CI 1.51-3.57), allergic rhinitis (OR 1.51; 95% CI 1.08-2.10), and sinusitis (OR 1.64; 95% CI 1.08-2.50). The network analysis of total patients revealed a positive interrelationship between asthma and allergic rhinitis, sinusitis, otitis media, atopic dermatitis, BMI, and RA. The interrelationship between asthma and sinusitis was stronger in the RA group. Of note, the relationship between asthma and BMI was distinctively found only in the RA group (r = 0.214, P < 0.05). In patients with asthma, the prevalence of obesity was 64% in the presence of RA, and 40% in the absence of RA (P = 0.034). Conclusion: This study supports the positive association of RA with asthma, allergic rhinitis, and sinusitis. Our analysis suggests a notable interrelationship between the presence of asthma and higher BMI values in patients with RA, indicating that asthma is more obesity-related in patients with RA.

Clinical phenotypes of chronic cough categorised by cluster analysis.

BACKGROUND: Chronic cough is a heterogeneous disease with various aetiologies that are difficult to determine. Our study aimed to categorise the phenotypes of chronic cough. METHODS: Adult patients with chronic cough were assessed based on the characteristics and severity of their cough using the COugh Assessment Test (COAT) and the Korean version of the Leicester Cough Questionnaire. A cluster analysis was performed using the K-prototype, and the variables to be included were determined using a correlation network. RESULTS: In total, 255 participants were included in the analysis. Based on the correlation network, age, score for each item, and total COAT score were selected for the cluster analysis. Four clusters were identified and characterised as follows: 1) elderly with mild cough, 2) middle-aged with less severe cough, 3) relatively male-predominant youth with severe cough, and 4) female-predominant elderly with severe cough. All clusters had distinct demographic and symptomatic characteristics and underlying causes. CONCLUSIONS: Cluster analysis of age, score for each item, and total COAT score identified 4 distinct phenotypes of chronic cough with significant differences in the aetiologies. Subgrouping patients with chronic cough into homogenous phenotypes could provide a stratified medical approach for individualising diagnostic and therapeutic strategies.

Unilateral diffuse alveolar haemorrhage with microscopic polyangiitis: A case report.

Diffuse alveolar haemorrhage (DAH) is a life-threatening condition caused by widespread damage to the small pulmonary vessels. Common chest imaging findings in patients with DAH show bilateral diffuse airspace opacities. DAH complicating antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, including microscopic polyangiitis, should be considered as a differential diagnosis in patients with progressive dyspnea, reduced haemoglobin levels, and alveolar opacities on chest imaging. We report the case of a 78-year-old woman who presented with unilateral DAH, severe dyspnea, and anaemia. DAH was confirmed using bronchoalveolar lavage. Laboratory test results, including ANCA, positive anti-myeloperoxidase antibody, and negative anti-proteinase 3, led to a diagnosis of microscopic polyangiitis. Rituximab and methylprednisolone were administered. The patient's symptoms, laboratory test results, and chest radiography findings improved after the initiation of treatment. This case highlights the importance of prompt recognition of clinical symptoms and signs, including dyspnea and anaemia, for the diagnosis of DAH.

Association of Underlying Comorbidities and Sites of tuberculosis: an analysis using surveillance data.

BACKGROUND: Tuberculosis (TB) is a highly heterogeneous disease that can affect any organ. Extrapulmonary TB (EPTB) is more difficult to diagnose due to various clinical presentations. Depending on the characteristics of the patient, the involved site of TB may vary. However, data on clinical characteristics of EPTB are inconsistent and insufficient. This study aimed to identify the characteristics of patients with pulmonary TB (PTB) and EPTB and describe characteristic differences for each involved site. METHODS: We systemically collected data of TB patients included in the national surveillance system in South Korea from July 2018 to June 2019 and compared the characteristics of patients with EPTB with that of PTB. RESULTS: A total of 7674 patients with a mean age of 60.9 years were included. Among them, 6038 (78.7%) patients were diagnosed with PTB and 1636 (21.3%) with EPTB. In PTB group, the mean age (61.7 ± 18.7 vs. 57.8 ± 19.9) and proportion of male sex (63.3% vs. 50.1%) were higher, but the body mass index was lower (21.2 ± 3.4 vs. 22.7 ± 3.5) than that of the EPTB group. Prevalence of diabetes (20.5% vs. 16.9%) and chronic lung disease (5.1% vs. 2.9%) were higher in PTB group, meanwhile, those of chronic kidney disease (CKD) (2.7% vs. 5.4%) and long-term steroid use (0.4% vs. 1.0%) were higher in EPTB group. Abdominal TB was more prevalent in patients with chronic liver disease (odds ratio [OR]: 2.69, 95% CI: 1.52-4.74), and urogenital TB was more prevalent in patients with CKD (OR: 2.75, 95% CI: 1.08-6.99). CONCLUSIONS: We found that underlying comorbidities were closely associated with the location of TB development, and therefore, the possibility of EPTB should be carefully evaluated while monitoring for underlying disease in TB-endemic areas.

Use of the Monoclonal Antibody Regdanvimab to Treat Patients Hospitalized with COVID-19: Real-World Data during the Delta Variant Predominance.

Regdanvimab is the only monoclonal antibody available in Korea that targets severe acute respiratory syndrome coronavirus 2. We retrospectively evaluated the clinical characteristics of 374 adults hospitalized with coronavirus disease 2019 (COVID-19) who were treated with regdanvimab from September through December 2021. In total, 322 (86.1%) patients exhibited risk factors for disease progression. Most patients (91.4%) improved without additional treatment. No patient died or was transferred to intensive care. This study shows that regdanvimab prevented disease progression in high-risk patients with mild to moderate COVID-19 infections during Delta variant predominance.