Background: The treatment success rate for tuberculosis (TB) has stagnated at 80–81% in South Korea, indicating unsatisfactory outcomes. Enhancing treatment success rate necessitates the development of individualized treatment approaches for each patient. This study aimed to identify the risk factors associated with unfavorable treatment outcomes to facilitate tailored TB care. Methods: We retrospectively analyzed the data of patients with active TB between January 2019 and December 2020 at a single tertiary referral center. We classified unfavorable treatment outcomes according to the 2021 World Health Organization guidelines as follows:“lost to follow-up” (LTFU), “not evaluated” (NE), “death,” and “treatment failure” (TF).Moreover, we analyzed risk factors for each unfavorable outcome using Cox proportional hazard regression analysis. Results: A total of 659 patients (median age 62 years; male 54.3%) were included in the study.The total unfavorable outcomes were 28.1%: 4.6% LTFU, 9.6% NE, 9.1% deaths, and 4.9% TF. Multivariate analysis showed that a culture-confirmed diagnosis of TB was associated with a lower risk of LTFU (adjusted hazard ratio [aHR], 0.25; 95% confidence interval [CI], 0.10–0.63), whereas the occurrence of adverse drug reactions (ADRs) significantly increased the risk of LTFU (aHR, 6.63; 95% CI, 2.63–16.69). Patients living far from the hospital (aHR, 4.47; 95% CI, 2.50–7.97) and those with chronic kidney disease (aHR, 3.21; 95% CI, 1.33–7.75) were at higher risk of being transferred out to other health institutions (NE). Higher mortality was associated with older age (aHR, 1.06; 95% CI, 1.04–1.09) and comorbidities. The ADRs that occurred during TB treatment were a risk factor for TF (aHR, 6.88; 95% CI, 2.24–21.13). Conclusion Unfavorable outcomes of patients with TB were substantial at a tertiary referral center, and the risk factors for each unfavorable outcome varied. To improve treatment outcomes, close monitoring and the provision of tailored care for patients with TB are necessary.

Background: Coinfections with multiple nontuberculous mycobacterial (NTM) species have not been widely studied. We aimed to evaluate the clinical characteristics and treatment outcomes in patients with NTM-pulmonary disease (PD) caused by coinfection with multiple NTM species. Methods: We retrospectively reviewed patients with NTM-PD at a tertiary referral hospital in Korea between March 2012 and December 2018. Coinfection was defined as two or more species of NTM pathogens isolated from the same respiratory specimen or different specimens within three months. Results: Among 1,009 patients with NTM-PD, 147 (14.6%) NTM coinfections were observed (average age 64.7 years, 69.4% women). NTM species were identified more frequently (median 6 vs. 3 times, P < 0.001) in the coinfection group than in the single species group, and follow-up duration was also longer in the coinfection group (median 44.9 vs. 27.1 months, P < 0.001). Mycobacterium avium complex (MAC) and M. abscessus and M. massiliense (MAB) were the dominant combinations (n = 71, 48.3%). For patients treated for over six months in the MAC plus MAB group (n = 31), sputum culture conversion and microbiological cure were achieved in 67.7% and 41.9% of patients, respectively. We divided the MAC plus MAB coinfection group into three subgroups according to the target mycobacteria; however, no statistical differences were found in the treatment outcomes. Conclusion In NTM-PD cases, a significant number of multiple NTM species coinfections occurred. Proper identification of all cultured NTM species through follow-up is necessary to detect multispecies coinfections. Further research is needed to understand the nature of NTM-PD in such cases.

Background: Brain metastases of peri-Rolandic area is crucial as it directly impacts the quality of life for cancer patients. Surgery or stereotactic radiosurgery (SRS) is considered for peri-Rolandic brain metastases as for other brain metastases. However, the benefit of each treatment modality on functional outcome has not been clearly defined for this tumor. The purpose of this study is to compare the functional course of each treatment and to suggest an effective treatment for patients’ quality of life. Methods: Fifty-two patients who had undergone SRS or surgery for brain metastasis confirmedby enhanced MRI were enrolled retrospectively. Overall survival (OS), progression free survival (PFS), and functional outcomes were estimated using the Kaplan-Meier method, univariate, multivariate analysis, and Cox proportional hazards regression. Results: Median OS and PFS were 13.3 months and 8.9 months in our study population.Treatment modalities were not significant factors for OS and PFS. Extracranial systemic cancer progression was significant factor for both parameters (p=0.030 for OS and p=0.040 for PFS). Median symptom improvement (improvement of at least 1 grade after surgery compared to preoperative state) time was significantly shorter in surgery group than in the SRS group (10.5 days vs. 37.5 days, p=0.034). Conclusion Surgery for brain metastases can contribute to a positive quality of life for the remain-ing duration of the patient’s life.

Background: Pyomyositis (PM) is a serious soft tissue infection and despite its clinical importance, previous studies have not been able to fully determine the clinical characteristics and microbial epidemiology of PM in Korea, which we therefore aimed to investigate. Materials and Methods: We retrospectively identified 140 adult patients diagnosed with PM from 13 general hospitals between January 2012 and December 2015. We analyzed the clinical and microbial characteristics of community-onset PM and compared them with communityacquired (CA) and healthcare-associated (HCA) PM. Results: One hundred eleven organisms were isolated from 96 (68.6%) patients with PM.Staphylococcus aureus (38 patients) was the most common pathogen, followed by streptococci (24 patients), and enteric Gram-negative organisms (27 patients). Methicillin-resistant S.aureus (MRSA) was identified in four (2.9%) patients and in-hospital mortality reached 8.6% (12/140). Enterococci isolates were identified in the HCA PM subgroup only The proportion of MRSA isolates was not comparable between CA and HCA PM subgroups. In the 83 patients with PM infected by monomicrobial pathogens, isolates of Gram-negative organisms were more commonly found in HCA PM subgroup than in CA PM subgroup (47.6% [10/21] of patients with HCA PM vs. 20.7% [12/58] of patients with CA PM; P = 0.01). Conclusion Gram-positive cocci such as S. aureus and streptococci were dominant etiologies in community-onset PM, whereas MRSA appears to an uncommon causative organism of PM in Korea. Enteric Gram-negative organisms should also be considered as major etiologies, especially in HCA PM patient population in Korea.

Purpose: We aimed to determine the relationship between environmental exposure and nontuberculous mycobacterial pulmonary disease (NTM-PD) in Korea. Materials and Methods: A group of 150 patients with NTM-PD and a control group of 217 patients with other respiratory diseases were prospectively enrolled between June 2018 and December 2020 in Seoul, Korea. They were surveyed with a standardized questionnaire, and their medical records were reviewed. Odds ratio (OR) and 95% confidence intervals (CI) were calculated with multivariate logistic regression analysis. Results: The mean ages of the NTM-PD and control groups were similar (63.8±9.2 years vs. 63.5±10.0 years; p=0.737), and most patients were female (76.0% vs. 68.7%; p=0.157) and nonsmokers (82.0% vs. 72.8%; p=0.021). Mycobacterium avium (49.3%) was the most commonly identified strain among NTM-PD patients, followed by M. intracellulare (32.0%) and M. abscessus subspecies massiliense (12.7%). There were no differences in housing type or frequency of soil- or pet-related exposure between the case and the control groups. However, in subgroup analysis excluding patients with M. intracellulare infection, more case patients frequently visited public baths ≥1 time/week (35.3% vs. 19.4%, p=0.003); this remained significant after multivariate analysis (OR, 2.84; 95% CI, 1.58–5.17). Conclusion Frequent exposure to water at public baths might affect the odds of contracting NTM-PD, excluding individuals infected with M. intracellulare strains.

Purpose: We aimed to determine the relationship between environmental exposure and nontuberculous mycobacterial pulmonary disease (NTM-PD) in Korea. Materials and Methods: A group of 150 patients with NTM-PD and a control group of 217 patients with other respiratory diseases were prospectively enrolled between June 2018 and December 2020 in Seoul, Korea. They were surveyed with a standardized questionnaire, and their medical records were reviewed. Odds ratio (OR) and 95% confidence intervals (CI) were calculated with multivariate logistic regression analysis. Results: The mean ages of the NTM-PD and control groups were similar (63.8±9.2 years vs. 63.5±10.0 years; p=0.737), and most patients were female (76.0% vs. 68.7%; p=0.157) and nonsmokers (82.0% vs. 72.8%; p=0.021). Mycobacterium avium (49.3%) was the most commonly identified strain among NTM-PD patients, followed by M. intracellulare (32.0%) and M. abscessus subspecies massiliense (12.7%). There were no differences in housing type or frequency of soil- or pet-related exposure between the case and the control groups. However, in subgroup analysis excluding patients with M. intracellulare infection, more case patients frequently visited public baths ≥1 time/week (35.3% vs. 19.4%, p=0.003); this remained significant after multivariate analysis (OR, 2.84; 95% CI, 1.58–5.17). Conclusion Frequent exposure to water at public baths might affect the odds of contracting NTM-PD, excluding individuals infected with M. intracellulare strains.

Background: Pyomyositis (PM) is a serious soft tissue infection and despite its clinical importance, previous studies have not been able to fully determine the clinical characteristics and microbial epidemiology of PM in Korea, which we therefore aimed to investigate. Materials and Methods: We retrospectively identified 140 adult patients diagnosed with PM from 13 general hospitals between January 2012 and December 2015. We analyzed the clinical and microbial characteristics of community-onset PM and compared them with communityacquired (CA) and healthcare-associated (HCA) PM. Results: One hundred eleven organisms were isolated from 96 (68.6%) patients with PM.Staphylococcus aureus (38 patients) was the most common pathogen, followed by streptococci (24 patients), and enteric Gram-negative organisms (27 patients). Methicillin-resistant S.aureus (MRSA) was identified in four (2.9%) patients and in-hospital mortality reached 8.6% (12/140). Enterococci isolates were identified in the HCA PM subgroup only The proportion of MRSA isolates was not comparable between CA and HCA PM subgroups. In the 83 patients with PM infected by monomicrobial pathogens, isolates of Gram-negative organisms were more commonly found in HCA PM subgroup than in CA PM subgroup (47.6% [10/21] of patients with HCA PM vs. 20.7% [12/58] of patients with CA PM; P = 0.01). Conclusion Gram-positive cocci such as S. aureus and streptococci were dominant etiologies in community-onset PM, whereas MRSA appears to an uncommon causative organism of PM in Korea. Enteric Gram-negative organisms should also be considered as major etiologies, especially in HCA PM patient population in Korea.

Background/Aims: Delayed diagnosis and treatment of smear-negative pulmonary tuberculosis (TB) are major concerns for TB control. We evaluated characteristics of patients with smear-negative pulmonary TB who received a delayed diagnosis and identified risk factors that may have contributed to this delay. Methods: We reviewed medical records of patients with smear-negative culture-positive pulmonary TB treated at a tertiary care hospital in South Korea between January 2017 and December 2018. Patients who initiated anti-TB treatment after positive cultures were included in the missed TB group, and those who initiated empirical treatment before positive cultures were included in the control group. Results: Of 220 patients included, 117 (53.2%) and 103 (46.8%) were in the missed TB and control groups, respectively. Patients in the missed TB group were older (p = 0.001) and had a higher mean body mass index (BMI) (p = 0.019). Comorbidities (66.9% vs. 46.6%, p = 0.003) and immunocompromised patients (33.1% vs. 20.4%, p = 0.035) were more common in the missed TB group than in the control group. Old age (odds ratio [OR], 1.030; 95% confidence interval [CI], 1.012 to 1.048; p = 0.001), high BMI (OR, 1.114; 95% CI, 1.004 to 1.237; p = 0.042), and negative polymerase chain reaction (PCR) results (OR, 9.551; 95% CI, 4.925 to 18.521; p < 0.001) were associated with delayed diagnosis. Conclusions In more than half of patients with smear-negative pulmonary TB, the diagnosis was delayed. Patients with delayed TB diagnosis were older, had higher BMI, and negative PCR results.

Background: Firefighters inevitably encounter emotionally and physically stressful situations at work. Even firefighters without diagnosed post-traumatic stress disorder receive clinical attention because the nature of the profession exposes them to repetitive trauma and high occupational stress. This study investigated gray matter abnormalities related to high occupational stress in firefighters using voxel-based morphometry (VBM) and surface-based morphometry (SBM). Methods: We assessed 115 subjects (112 males and 3 females) using magnetic resonance imaging and evaluated occupational stress by the Korean Occupational Stress Scale-26 (KOSS-26). Subjects were classified into highly or lowly stressed groups based on the median value of the KOSS-26. Results: In VBM analysis, we found that firefighters with high occupational stress had lower gray matter volume (GMV) in both sides of the insula, the left amygdala, the right medial prefrontal cortex (mPFC), and the anterior cingulate cortex than firefighters with low occupational stress. In SBM analysis based on regions of interest, the GMV of the bilateral insula and right mPFC were also lower in the highly stressed group. Within the highly stressed group, low GMV of the insula was significantly correlated with the length of service (left: r = −0.347, P = 0.009; right: r = −0.333, P = 0.012). Conclusion Our findings suggest that regional GMV abnormalities are related to occupational stress. Regional gray matter abnormalities and related emotional dysregulation may contribute to firefighter susceptibility to burnout.

Asthma ; Bronchitis ; Cohort Studies ; Cough ; Diagnosis ; Disease Management ; Eosinophils ; Epidemiology ; Female ; Gastroesophageal Reflux ; Humans ; Korea ; Lung Diseases ; Multivariate Analysis ; Observational Study ; Pregnant Women ; Retrospective Studies ; Tuberculosis