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: Recent reports have suggested that pneumonitis is a rare complication following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).However, its clinical features and outcomes are not well known. The aim of this study was to identify the clinical characteristics and outcomes of patients with vaccine-associated pneumonitis following vaccination against SARS-CoV-2. Methods: In this nationwide multicenter survey study, questionnaires were distributed to pulmonary physicians in referral hospitals. They were asked to report cases of development or exacerbation of interstitial lung disease (ILD) associated with the coronavirus disease 2019 vaccine. Vaccine-associated pneumonitis was defined as new pulmonary infiltrates documented on chest computed tomography within 4 weeks of vaccination and exclusion of other possible etiologies. Results: From the survey, 49 cases of vaccine-associated pneumonitis were identified between February 27 and October 30, 2021. After multidisciplinary discussion, 46 cases were analyzed. The median age was 66 years and 28 (61%) were male. The median interval between vaccination and respiratory symptoms was 5 days. There were 20 (43%), 17 (37%), and nine (19%) patients with newly identified pneumonitis, exacerbation of pre-diagnosed ILD, and undetermined pre-existing ILD, respectively. The administered vaccines were BNT162b2 and ChAdOx1 nCov-19/AZD1222 each in 21 patients followed by mRNA-1273 in three, and Ad26.COV2.S in one patient. Except for five patients with mild disease, 41 (89%) patients were treated with corticosteroid. Significant improvement was observed in 26 (57%) patients including four patients who did not receive treatment. However, ILD aggravated in 9 (20%) patients despite treatment. Mortality was observed in eight (17%) patients. Conclusion These results suggest pneumonitis as a potentially significant safety concern for vaccines against SARS-CoV-2. Clinical awareness and patient education are necessary for early recognition and prompt management. Additional research is warranted to identify the epidemiology and characterize the pathophysiology of vaccine-associated pneumonitis.

Purpose: Assessing lymph node metastasis, tumor-derived DNA, or tumor-derived RNA has previously been studied in place of immunohistochemical assay. Because a direct reverse transcription loop-mediated isothermal amplification method (direct RT-LAMP) has been previously developed in order to rapidly identify viruses in place of RNA extraction, our team hypothesized that a direct RT-LAMP assay can be employed as a substitute in order to detect tumor involvement of lymph nodes within breast cancer patients. Materials and Methods: A total amount of 92 lymph nodes removed across 40 patients possessing breast cancer were collected at Kyungpook National University Chilgok Hospital between the months of November 2015 and February 2016. All samples were then evaluated and contrasted via both a direct RT-LAMP assay and routine histopathologic examination. Results: The sensitivity and specificity of the direct RT-LAMP assay were 85.7% and 100%, respectively. The positive predictive value and negative predictive value were 100% and 94.4%, respectively. Conclusion Direct RT-LAMP assay is capable of facilitating the detection of sentinel lymph node metastasis within breast cancer patients intraoperatively possessing an excellent sensitivity via a cost-effective and time-saving manner.

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/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.

Purpose: Isoniazid (INH) mono-resistant tuberculosis (Hr-TB) is a highly prevalent type of drug-resistant TB, possibly associated with unfavorable treatment outcomes. However, definitive guidelines on an optimal treatment regimen and duration for Hr-TB are currently under discussion. We evaluated the characteristics and treatment outcomes of Hr-TB patients. Materials and Methods: We retrospectively reviewed the medical records of Hr-TB patients treated at a South Korean tertiary referral hospital from January 2005 to December 2018. Results: We included 195 Hr-TB patients. 113 (57.9%) were male, and the median age was 56.6 [interquartile range, 40.2–68.6] years. Mutations in katG were the most frequent [54 (56.3%)], followed by those in the inhA [34 (35.4%)]. Favorable and unfavorable outcomes were noted in 164 (84.1%) and 31 (15.9%) patients, respectively. Smoking history [odds ratio (OR)=5.606, 95% confidence interval (CI): 1.695–18.543, p=0.005], low albumin level (OR=0.246, 95% CI: 0.104–0.578, p=0.001), and positive acid-fast bacilli culture at 2 months (OR=7.853, 95% CI: 1.246–49.506, p=0.028) were associated with unfavorable outcomes. Conclusion A tailored strategy targeting high-risk patients is imperative for improved treatment outcomes. Further research on the rapid and accurate detection of resistance to INH and other companion drugs is warranted.

Objective: To compare short-term treatment outcomes at hospital discharge and hospital length of stay (LOS) in patients with spontaneous intracerebral hemorrhage (sICH) before and after introduction of resident physician work time limit (WTL). Methods: We retrospectively reviewed consecutive patients treated for sICH at our institution between 2016 and 2019. Then we dichotomized these patients into two groups, pre-WTL and post-WTL. We analyzed demographic elements and clinical features, and hospital length of stay (LOS). We evaluated short-term outcome using modified Rankin scale score at hospital discharge and then divided it into “good” and “poor” outcome groups. We subsequently, compared short-term treatment outcome and hospital LOS between the pre-WTL and post-WTL groups. Results: Out of 779 patients, 420 patients (53.9%) were included in the pre-WTL group, and 359 (46.1%) in post-WTL. The mortality rate in sICH patients was higher in the post-WTL group (pre-WTL; 13.6% vs. post-WTL; 17.3%), but there was no statistically significant difference in short-term outcome including mortality (p=0.332) between the groups. The LOS also, was not significantly different between the two groups (pre-WTL; 19.0 days vs. post-WTL; 20.2 days) (p=0.341). The initial Glasgow Coma Scale score, personal stroke history, and mean age were the only independent outcome predicting factors for patients with sICH. Conclusions Some neurosurgeons may expect poorer outcome for sICH after implementation of the WTL of the K-MHW for resident physician however, enforcement of the WTL did not significantly influence the short-term outcome and hospital LOS for sICH in our hospital. Further well-designed multi-institutional prospective studies on the effects of WTL in sICH patient outcome, are anticipated.

PURPOSE: To identify prognostic factors for the outcomes of empirical antifungal therapy, we performed a multicenter, prospective, observational study in immunocompromised patients with hematological malignancies. MATERIALS AND METHODS: Three hundred seventy-six patients (median age of 48) who had neutropenic fever and who received intravenous (IV) itraconazole as an empirical antifungal therapy for 3 or more days were analyzed. The patients with possible or probable categories of invasive fungal disease (IFD) were enrolled. RESULTS: The overall success rate was 51.3% (196/376). Age >50 years, underlying lung disease (co-morbidity), poor performance status [Eastern Cooperative Oncology Group (ECOG) > or =2], radiologic evidence of IFD, longer duration of baseline neutropenic fever (> or =4 days), no antifungal prophylaxis or prophylactic use of antifungal agents other than itraconazole, and high tumor burden were associated with decreased success rate in univariate analysis. In multivariate analysis, age >50 years (p=0.009) and poor ECOG performance status (p=0.005) were significantly associated with poor outcomes of empirical antifungal therapy. Twenty-two patients (5.9%) discontinued itraconazole therapy due to toxicity. CONCLUSION: We concluded that empirical antifungal therapy with IV itraconazole in immunocompromised patients is effective and safe. Additionally, age over 50 years and poor performance status were poor prognostic factors for the outcomes of empirical antifungal therapy with IV itraconazole.
Antifungal Agents/adverse effects/*therapeutic use ; Female ; Hematologic Neoplasms ; Humans ; Immunocompromised Host ; Itraconazole/adverse effects/*therapeutic use ; Male ; Middle Aged ; Prospective Studies ; Republic of Korea