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BackgroundMolecular screening using next-generation sequencing (NGS) in the pathologic evaluation of lung cancer is considered the standard in clinical practice; hence, we evaluated the diagnostic yields of various sampling methods for NGS.MethodsNGS data from patients with lung cancer at the Pusan National University Hospital (Busan, South Korea), admitted October, 2020–April, 2023, was obtained. The sampling methods by which NGS data was obtained were divided into surgical and nonsurgical. Surgical methods included thoracoscopic surgery, surgical biopsy from the metastatic site, and lymph node excisional biopsy, whereas nonsurgical methods included bronchoscopy procedures and medical thoracoscopic biopsy.ResultsIn total, we obtained 319 patients’ NGS data:150 (47.0%) and 169 (53.0%) was obtained using surgical and nonsurgical methods, respectively. The overall diagnostic yield of NGS analysis was 97.5% for all samples. There were no significant differences in the success rates of deoxyribonucleic acid sequencing between surgical and nonsurgical sampling methods (98.0% vs. 96.4%, p = 0.313). On the other hand, the success rate of ribonucleic acid (RNA) sequencing was significantly lower in the surgical method group (78.0% vs. 92.3%; p < 0.001). Multivariate analysis showed that surgical sampling significantly correlated with RNA sequencing failure (Odd Ratio 4.128, 95% Confidence Interval 1.681–10.133, p = 0.002).ConclusionsSmall samples obtained using nonsurgical procedures are suitable for NGS analysis in clinical practice. However, surgical sampling showed a relatively lower success rate for RNA sequencing than nonsurgical sampling. This information may help in the development of protocols to reduce RNA degradation during the surgical process.

After the successful development of targeted therapy and immunotherapy for the treatment of advanced-stage non-small cell lung cancer (NSCLC), these innovative treatment options are rapidly being applied in the adjuvant setting for early-stage NSCLC. Some adjuvants that have recently been approved include osimertinib for epidermal growth factor receptor-mutated tumors and atezolizumab and pembrolizumab for selected patients with resectable NSCLC. Numerous studies on various targeted therapies and immunotherapy with or without chemotherapy are currently ongoing in the adjuvant setting. However, several questions regarding optimal strategies for adjuvant treatment remain unanswered. The present review summarizes the available literature, focusing on recent advances and ongoing trials with targeted therapy and immunotherapy in the adjuvant treatment of early-stage NSCLC.

Since the introduction of low-dose computed tomography (CT) screening for patients at high risk of lung cancer, the detection rate of suspicious lung cancer has increased. In addition, there have been many advances in therapeutics targeting oncogenic drivers in non-small cell lung cancer. Therefore, accurate pathological diagnosis of lung cancer, including molecular diagnosis, is increasingly important. This review examines the problems in the pathological diagnosis of suspected lung cancer. For successful pathological diagnosis of lung cancer, clinicians should determine the appropriate modality of the diagnostic procedure, considering individual patient characteristics, CT findings, and the possibility of complications. Furthermore, clinicians should make efforts to obtain a sufficient amount of tissue sample using non- or less-invasive procedures for pathological diagnosis and biomarker analysis.

Background/Aims Despite the obvious benefits of adding immune checkpoint inhibitors to platinum-etoposide chemotherapy in patients with extensive-stage small-cell lung cancer (ES-SCLC), real-world data remain scarce. Methods This retrospective study included 89 patients with ES-SCLC treated with platinum-etoposide chemotherapy alone (chemo-only group; n = 48) or in combination with atezolizumab (atezolizumab group; n = 41) and compared the survival outcomes between these two groups. Results Overall survival (OS) was significantly longer in the atezolizumab group than in the chemo-only group (15.2 months vs. 8.5 months; p = 0.047), whereas the median progression-free survival was almost the same (5.1 months vs. 5.0 months) in both groups (p = 0.754). Subsequent multivariate analysis revealed that thoracic radiation (hazard ratio [HR], 0.223; 95% confidence interval [CI], 0.092–0.537; p = 0.001) and atezolizumab administration (HR, 0.350; 95% CI, 0.184–0.668; p = 0.001) were favorable prognostic factors for OS. In the thoracic radiation subgroup, patients who received atezolizumab demonstrated favorable survival outcomes and no grade 3–4 adverse events (AEs). Conclusions The addition of atezolizumab to platinum-etoposide resulted in favorable outcomes in this real-world study. Thoracic radiation was associated with improved OS and acceptable AE risk in combination with immunotherapy in patients with ES-SCLC.

IntroductionIn 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.MethodsA 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.ResultsA 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)].ConclusionIdentifying 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.

ObjectiveTuberculosis (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.MethodsData 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.ResultsOf 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.ConclusionPatients 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.

Abstract Background Studies on the application of targeted therapies for patients with non‐small cell lung cancer (NSCLC) who harbor rare genetic mutations are ongoing. In the present study, we investigated the real‐world data of NSCLC patients who harbor rare mutations. Methods We retrospectively analyzed patients with advanced or metastatic nonsquamous NSCLC aged >20 years with confirmed rare mutations (BRAF, ROS1, MET, RET, HER2, FGFR, and NTRK) from January 2015 to September 2020 at nine tertiary hospitals. In addition, we validated the lung cancer PCR panel kit in patients with confirmed mutations by NGS. Results Among 118 patients included, 88 received platinum‐based chemotherapy as first‐line chemotherapy. The progression‐free survival of patients with BRAF, ERBB2, MET, RET, and ROS1 mutations was 10.9 months (95% confidence interval [CI]: 1.3–20.5), 5.3 months (95% CI: 3.0–7.5), 7.2 months (95% CI: 3.6–10.9), 11.4 months (95% CI: 9.2–13.6), and 10.0 months (95% CI: 3.7–16.4) respectively (p = 0.041). The median overall survival (OS) was not reached in patients with ROS1 mutations; however, in BRAF, ERBB2, MET, and RET mutant patients, median OS was 14.1 months (95% CI: 10.1–14.1), 34.5 months (95% CI: 13.2–36.9), 22.7 months (95% CI: 1.7–24.0), and 29.8 months (95% CI: 28.9–61.3), respectively (p = 0.006). Of the 27 tissue samples, 26 (96.3%) showed the same PCR panel kit result with NGS. Conclusions First‐line platinum‐based chemotherapy showed durable benefit in patients with advanced or metastatic nonsquamous NSCLC harboring rare genetic mutation other than EGFR or ALK.

Background and Objectives: BRAF mutational status in resected non-small cell lung cancer (NSCLC) in the Korean population is poorly understood. We explored BRAF (particularly BRAF V600E) mutational status among Korean patients with NSCLC. Materials and Methods: This study included 378 patients with resected primary NSCLC who were enrolled from January 2015 to December 2017. The authors obtained formalin-fixed paraffin-embedded (FFPE) tissue blocks and performed peptide nucleic acid (PNA)-clamping polymerase chain reaction (PCR) for detecting BRAF V600, real-time PCR for detecting BRAF V600E, and immunohistochemical analyses using the mutation-specific Ventana VE1 monoclonal antibody. For positive cases in any methods mentioned above, direct Sanger sequencing was additionally performed. Results: The PNA-clamping method revealed the BRAF V600 mutation in 5 (1.3%) of the 378 patients. Among these five patients, real-time PCR, direct Sanger sequencing detected BRAF V600E mutations in three (0.8%) patients. Thus, two cases showed differences in their PNA-clamping and the others. Direct Sanger sequencing of PNA-clamping PCR product was performed for two cases showing negative results on direct Sanger sequencing; both contained BRAF mutations other than V600E. All patients harboring BRAF mutations had adenocarcinomas, and all patients with V600E mutation exhibited minor micropapillary components. Conclusions: Despite the low incidence of the BRAF mutation among Korean patients with NSCLC, lung adenocarcinoma patients with micropapillary components should be prioritized in terms of BRAF mutation testing. Immunohistochemical staining using Ventana VE1 antibody may serve as a screening examination for BRAF V600E.

Background This study compared the treatment outcomes of patients with multidrug-resistant tuberculosis (MDR-TB) before and after the implementation of public–private mix (PPM). Factors affecting treatment success were also investigated. Methods Data from culture-confirmed pulmonary MDR-TB patients who commenced MDR-TB treatment at Pusan National University Hospital between January 2003 and December 2017 were retrospectively reviewed. Patients were divided into two groups in terms of PPM status: pre-PPM period, patients who commenced MDR-TB treatment between 2003 and 2010; and post-PPM period, patients treated between 2011 and 2017. Results A total of 176 patients were included (64 and 112 in the pre- and post-PPM periods, respectively). 36.9% of the patients were resistant to a fluoroquinolone or a second-line injectable drug, or both. The overall treatment success rate was 72.7%. The success rate of post-PPM patients was higher than that of pre-PPM patients (79.5% vs. 60.9%, p=0.008). Also, loss to follow-up was lower in the post-PPM period (5.4% vs. 15.6%, p=0.023). In multivariate regression analysis, age ≥65 years, body mass index ≤18.5 kg/m2, previous TB treatment, bilateral lung involvement, and extensively drug-resistant (XDR)- or pre-XDR-TB were associated with poorer treatment outcomes. However, the use of bedaquiline or delamanid for ≥1 month increased the treatment success. Conclusion The treatment success rate in MDR-TB patients was higher in the post-PPM period than in the pre-PPM period, particularly because of the low rate of loss to follow-up. To ensure comprehensive patient-centered PPM in South Korea, investment and other support must be adequate.

Background The occurrence of multidrug-resistant (MDR) bacteremia in ventilated patients may be associated with a high mortality rate. We evaluated whether Sequential Organ Failure Assessment (SOFA) score on the day of bacteremia could predict 90-day mortality in these patients. Methods Data were obtained retrospectively from 202 patients (male, 60.4%; median age, 64 years) hospitalized at a single university-affiliated tertiary care hospital. All adult patients who had were ventilated and had one of the following six MDR bacteremias between March 2011 and February 2018 were enrolled: methicillin-resistant Staphylococcus aureus, extended-spectrum β-lactamase-producing Gram-negative bacteria (Escherichia coli and Klebsiella pneumonia), carbapenem-resistant Gram-negative rods (Acinetobacter baumannii and Pseudomonas aeruginosa), or vancomycin-resistant Enterococcus faecium. Results The overall 90-day mortality rate after the day of bacteremia was 59.9%. The areas under the receiver operating characteristic curves for the SOFA and Acute Physiology and Chronic Health Evaluation (APACHE) II scores were 0.732 (95% confidence interval [CI], 0.666 to 0.792; P

We aimed to identify the association between sleep deprivation and inflammatory response. Fourteen-week old male Wistar rats were used randomly assigned to a sleep deprivation [sleep deprivation (SD) group, n = 3] or a control [healthy sleep (HS) group, n = 3] group. To induce sleep deprivation, we used a modified multiple platform method. We examined serum interleukin-1beta (IL-1β), corticosterone, the number of inflammatory cells in broncho-alveolar lavage fluid (BALF), and the histopathology of the pulmonary parenchyma (peri-bronchiolar infiltration) between the SD and the HS groups. The SD group showed an increase in serum IL-1β, corticosterone, the number of neutrophil and eosinophil in BALF, and peri-bronchiolar infiltration of eosinophils compared to the HS group. However, serum IL-1β and the number of inflammatory cells in BALF, except for corticosterone and eosinophil in lung parenchyma, were statistically insignificant. We suggest that SD may be associated with worsening of allergic inflammatory response.

Background. Ultrasound-guided percutaneous dilatational tracheostomy (US-PDT) has been adapted for use in intensive care units (ICU). US-PDT is comparable to bronchoscopy-assisted tracheostomy. However, compared to surgical tracheostomy (ST), its safety and effectiveness have not been well studied. Objectives. To determine the efficacy and safety of US-PDT compared to ST. Materials and Methods. A total of 90 patients who underwent US-PDT (n = 36) or ST (n = 54) between July 2019 and September 2020 were enrolled. US-PDT was performed in the ICU without a surgical assistant or bronchoscope. Data were collected retrospectively and analyzed regarding clinical characteristics, procedure times and details, complications, and mortality rate. Results. The success rate of US-PDT was 97.4% and the procedure time was shorter than ST (5.2 ± 3.1 vs. 10.5 ± 5.0 min). There were no significant differences in clinical characteristics and procedure details. There was no procedure-related mortality in either of the groups. Conclusions. US-PDT is time-efficient and as safe as ST. Based on our results, US-PDT may be considered a potential alternative to ST in high-risk patients and in those who cannot be transported.

Background and Objectives: Endobronchial ultrasound transbronchial lung biopsy with guide sheath (EBUS-GS-TBLB) has been regarded as a reasonable diagnostic method with an acceptable diagnostic yield. In addition, EBUS-GS-TBLB is considered safer and less invasive compared to percutaneous needle biopsy and thoracoscopic surgery. However, we encountered a case of life-threatening procedure-related fatal infection, which was successfully managed. Case presentation: A 61-year-old man with a 30 pack-year smoking history was referred to our clinic with a necrotic lung mass in the right middle lobe on a chest computed tomography scan. EBUS-GS-TBLB was performed for a pathological diagnosis without immediate complications. Eight days after the procedure, the patient visited the hospital with sudden hemoptysis and severe dyspnea with fever. A chest computed tomography revealed a ruptured lung abscess and pneumonia, developed after EBUS-GS-TBLB. Extracorporeal membrane oxygenation (ECMO) and mechanical ventilation were initiated to manage refractory hypoxia. While maintaining ECMO, video-assisted thoracoscopic surgery was performed at the patient’s bedside in the intensive care unit. After surgery, the patient’s vital signs gradually improved, and a chest computed tomography revealed a reduction in the extent of the lung abscess. Results: Although EBUS-GS-TBLB is minimally invasive and relatively safe when used for the diagnosis of peripheral lung lesions, pulmonary physicians should be aware of this rare but critical complication. Conclusions: We suggest that the careful prescription of prophylactic antibiotics before EBUS-GS-TBLB would be wise if the mass featured a necrotic, cavitary, or cystic lesion.

Background/Aims Matrix-assisted laser desorption/ionization time-of-f light mass spectrometry (MALDI-TOF MS) is a new diagnostic tool for microorganism identification. The clinical usefulness of this approach has not been widely examined in Korea. This retrospective pre–post-intervention quasi-experimental study examined the effect of MALDI-TOF MS on patients with multidrug-resistant (MDR) bacteremia in the intensive care unit (ICU). Methods All consecutive patients with MDR bacteremia in the ICU of a tertiary care hospital between March 2011 and February 2013 and between March 2014 and February 2016 were enrolled. MALDI-TOF MS was introduced between these periods. In the pre-intervention and intervention groups, microorganisms were identified by conventional means and by MALDI-TOF MS, respectively. The groups were compared in terms of time from venipuncture to microorganism identification and antimicrobial susceptibility test results. Results In total, 187 patients (mean age, 61.0 years; 56.7% male) were enrolled. Of these, 97 and 90 were in the pre-intervention and intervention groups, respectively. The intervention group had a significantly shorter time from venipuncture to microorganism identification and antimicrobial susceptibility test results (82.5 ± 21.6 hours vs. 92.3 ± 40.4 hours, p = 0.038). The antibiotics were adjusted in 52 patients (26 each in the pre-intervention and intervention groups) based on these results. These groups did not differ in terms of time from venipuncture to antibiotic adjustment, and multivariate regression analysis showed that MALDI-TOF MS–based microorganism identification was not associated with 28-day mortality. Conclusions Our study showed that MALDI-TOF MS accelerated microorganism identification in patients with MDR bacteremia, but did not inf luence 28-day mortality.

Abstract Background Myelolipoma is a rare benign tumor composed of mature adipose and hematopoietic tissues. Most myelolipomas are found in the adrenal glands, whereas intrathoracic myelolipoma is extremely rare. In particular, bronchial myelolipoma without the involvement of lung parenchyma has never been reported. Case presentation A previously healthy 38-year-old male developed dyspnea and a productive cough. Computed tomography revealed an endobronchial mass at the right bronchus intermedius and subsequent atelectasis of the right middle and lower lobes. Flexible bronchoscopy found a total obstruction of the right bronchus intermedius due to an endobronchial tumor. Using a rigid bronchoscope, the endobronchial tumor was resected and the base of the tumor was additionally ablated with a diode laser to prevent recurrence. The removed endobronchial tumor was a 13 mm × 20 mm-sized oval-shaped mass and was pathologically diagnosed as bronchial myelolipoma. Chest radiographs, obtained on the day following the procedure, showed an improvement of atelectasis, and accompanying symptoms were immediately improved. Follow-up bronchoscopy performed after 12 months evidenced no recurrence of the bronchial myelolipoma. Conclusions We used bronchoscopic intervention in patients with solitary bronchial myelolipoma and there was no evidence of recurrence.

Abstract Background Generally, structural destruction of lung parenchyma, such as pulmonary emphysema, is considered to be related to the low diagnostic yields and high complication rates of lung biopsies of peripheral lung lesions. Currently, little is known about the clinical outcomes of using endobronchial ultrasound with a guide sheath (EBUS-GS) to diagnose peripheral lesions in patients with emphysema. Methods This retrospective study was performed to identify the clinical outcomes of EBUS-GS in patients with pulmonary emphysema. This study included 393 consecutive patients who received EBUS-GS between February 2017 and April 2018. The patients were classified according to the severity of their emphysema, and factors possibly contributing to a successful EBUS-GS procedure were evaluated. Results The overall diagnostic yield of EBUS-GS in patients with no or mild emphysema was significantly higher than in those with moderate or severe pulmonary emphysema (78% vs. 61%, P = 0.007). There were no procedure-related complications. The presence of a bronchus sign on CT (P

Background The presence of EGFR mutation in patients with advanced non‐small cell lung cancer (NSCLC) plays an important role in determining the appropriate treatment, response, and survival. Therefore, this study attempted to predict the prognosis of NSCLC patients using data from quantitative mutation measurements. Methods The data of patients with advanced NSCLC who underwent EGFR mutation testing using the peptide nucleic acid (PNA) mediated clamping method at the Pusan National University Hospital from October 2015 to December 2017 were retrospectively analyzed. The efficiency of PNA clamping was determined by measuring the threshold cycle (Ct) value. The ΔCt−1 value (standard Ct value minus sample Ct value) was calculated to quantify EGFR mutation. Results During the study period, 71 patients were treated with EGFR‐tyrosine kinase inhibitors. The cutoff point for the ΔCt−1 value derived from the receiver operating characteristic curve was 5.32. A survival benefit was observed in the group with an ΔCt−1 value > 5.32 or with a common EGFR mutation type compared to the group with an ΔCt−1 value < 5.32. Conclusion EGFR mutation testing using PNA clamping may predict patient survival, especially in patients with common EGFR mutations, such as exon 19 deletion or L858R. A higher ΔCt−1 value correlates with better survival.

Abstract Background The diagnostic yields and safety profiles of transbronchial lung biopsy have not been evaluated in inexperienced physicians using the combined modality of radial probe endobronchial ultrasound and a guide sheath (EBUS-GS). This study assessed the utility and safety of EBUS-GS during the learning phase by referring to a database of performed EBUS-GS procedures. Methods From December 2015 to January 2017, all of the consecutive patients who underwent EBUS-GS were registered. During the study period, two physicians with no previous experience performed the procedure. To assess the diagnostic yields, learning curve, and safety profile of EBUS-GS performed by these inexperienced physicians, the first 100 consecutive EBUS-GS procedures were included in the evaluation. Results The overall diagnostic yield of EBUS-GS performed by two physicans in 200 patients with a peripheral lung lesion was 73.0%. Learning curve analyses showed that the diagnostic yields were stable, even when the procedure was performed by beginners. Complications related to EBUS-GS occurred in three patients (1.5%): pneumothorax developed in two patients (1%) and resolved spontaneously without chest tube drainage; another patient (0.5%) developed a pulmonary infection after EBUS-GS. There were no cases of pneumothorax requiring chest tube drainage, severe hemorrhage, respiratory failure, premature termination of the procedure, or procedure-related mortality. Conclusions EBUS-GS is a safe and stable procedure with an acceptable diagnostic yield, even when performed by physicians with no previous experience.

Background Patients with acute respiratory failure secondary to tuberculous destroyed lung (TDL) have a poor prognosis. The aim of the present retrospective study was to develop a mortality prediction model for TDL patients who require mechanical ventilation. Methods Data from consecutive TDL patients who had received mechanical ventilation at a single university-affiliated tertiary care hospital in Korea were reviewed. Binary logistic regression was used to identify factors predicting intensive care unit (ICU) mortality. A TDL on mechanical Ventilation (TDL-Vent) score was calculated by assigning points to variables according to β coefficient values. Results Data from 125 patients were reviewed. A total of 36 patients (29%) died during ICU admission. On the basis of multivariate analysis, the following factors were included in the TDL-Vent score: age ≥65 years, vasopressor use, and arterial partial pressure of oxygen/fraction of inspired oxygen ratio

BackgroundThis study investigated the time to appropriate treatment and factors affecting late treatment initiation in patients with multidrug-resistant tuberculosis (MDR-TB) in South Korea.MethodsData from patients with culture-confirmed pulmonary MDR-TB who received treatment at Pusan National University Hospital (PNUH) between January 2010 and July 2018 were reviewed retrospectively. Patients were divided into two groups according to the first institution they visited [patients who were transferred to PNUH after diagnosis of MDR-TB (Group A) and patients who were initially diagnosed with TB at PNUH (Group B)].ResultsA total of 100 patients were included (53 in Group A and 47 in Group B). The percentage of patients in whom line probe assays (LPAs) for isoniazid and rifampin or Xpert MTB/RIF assays were performed was higher in Group B than in Group A [20.8 vs. 57.4% (P < 0.001) and 17.0 vs. 46.8% (P = 0.001), respectively]. The median time from the first visit to appropriate treatment initiation was longer in Group A (102.0 vs. 77.0 days, P = 0.002). However, a subgroup analysis of patients with pre-extensively or extensively drug-resistant TB (pre-XDR- or XDR-TB) revealed that the time to appropriate treatment did not differ between Groups A and B. Although the time to appropriate treatment decreased during the study period in both Groups A and B, this trend was not evident in patients with pre-XDR- or XDR-TB in Group B. Based on multivariate analyses, performance of LPAs for isoniazid and rifampin, performance of Xpert MTB/RIF assays, and the presence of uncomplicated MDR-TB were protective against delays in appropriate treatment initiation.ConclusionsThe time to appropriate treatment in patients with MDR-TB in South Korea was not acceptable, particularly for patients diagnosed outside of PNUH and for patients with pre-XDR- or XDR-TB. The use of rapid molecular drug susceptibility tests in various healthcare settings and introduction of second-line LPAs are required.

BackgroundRadial probe endobronchial ultrasound using a guide sheath (EBUS-GS) is used to diagnose peripheral lung cancer. The aim was to identify the accuracy of molecular analysis that were performed with EBUS-GS specimens in patients with non-small cell lung cancer (NSCLC).MethodFrom December 2015 to September 2017, we retrospectively studied 91 patients with peripheral NSCLC who underwent surgery after EBUS-GS. Epidermal growth factor receptor (EGFR) mutational and anaplastic lymphoma kinase (ALK) translocation status obtained from surgical specimens served as the references.ResultsCompared to the reference data, EGFR mutational testing of EBUS-GS specimens was in 97% agreement, and the κ coefficient was 0.931 (P< 0.001). In addition, on ALK translocation testing, the results of all 91 patients were in agreement with the reference data (concordance rate of 100%, κ coefficient 1.000; P< 0.001).ConclusionWe found that EBUS-GS could be used for molecular diagnosis, such as EGFR mutational and ALK translocation status, in patients with peripheral NSCLC.

We aimed to develop a decision tree model to improve diagnostic performance of positron emission tomography/computed tomography (PET/CT) to detect metastatic lymph nodes (LN) in non-small cell lung cancer (NSCLC). 115 patients with NSCLC were included in this study. The training dataset included 66 patients. A decision tree model was developed with 9 variables, and validated with 49 patients: short and long diameters of LNs, ratio of short and long diameters, maximum standardized uptake value (SUVmax) of LN, mean hounsfield unit, ratio of LN SUVmax and ascending aorta SUVmax (LN/AA), and ratio of LN SUVmax and superior vena cava SUVmax. A total of 301 LNs of 115 patients were evaluated in this study. Nodular calcification was applied as the initial imaging parameter, and LN SUVmax (≥3.95) was assessed as the second. LN/AA (≥2.92) was required to high LN SUVmax. Sensitivity was 50% for training dataset, and 40% for validation dataset. However, specificity was 99.28% for training dataset, and 96.23% for validation dataset. In conclusion, we have developed a new decision tree model for interpreting mediastinal LNs. All LNs with nodular calcification were benign, and LNs with high LN SUVmax and high LN/AA were metastatic Further studies are needed to incorporate subjective parameters and pathologic evaluations into a decision tree model to improve the test performance of PET/CT.

BACKGROUND: The aim of this study is to describe the clinical course and outcome of patients who were diagnosed with acute respiratory distress syndrome (ARDS) caused by scrub typhus and who received ventilator care in the intensive care units (ICU) of two university hospitals. METHODS: We performed a retrospective analysis of all adult ventilated patients who were diagnosed with ARDS caused by scrub typhus. RESULTS: Eleven (1.7%) of 632 scrub typhus patients were diagnosed with ARDS (median age 72; seven were male). Eight patients had underlying diseases, the most common of which was hypertension (four patients). Eight patients (72.7%) were admitted in November. The most common chief complaints of the patients were fever and rash (63.6%). All patients had skin eschar and rash; seven were treated for shock. On the day of diagnosis with ARDS, the median Acute Physiology and Chronic Health Evaluation score was 20 (range 11-28) and Sequential Organ Failure Assessment score was 7 (range 4-14). All patients had PaO2/FiO2 < 200 mmHg, high serum aspartate aminotransferase level (> 40 IU/L), and hypoalbuminemia (< 3.3 g/dl). Nine patients were treated with doxycycline on the day of admission. Their median lengths of stay in the ICU and hospital were 10 (range 4-65) and 14 (4-136) days, respectively. The mortality rate during treatment in the hospital was 36.4%. CONCLUSIONS: In our study, the risk of ARDS among patients diagnosed with scrub typhus was at least 1.7%, with a hospital mortality rate of 36.4%.

Lung adenocarcinomas can be classified into terminal respiratory unit (TRU) and non-TRU types. We previously reported that non-TRU-type adenocarcinoma has unique clinical and morphological features as compared to the TRU type. Here we investigated whether micro (mi)RNA expression profiles can be used to distinguish between these two subtypes of lung adenocarcinoma. The expression of 1205 human and 144 human viral miRNAs was analyzed in TRU- and non-TRU-type lung adenocarcinoma samples (n = 4 each) by microarray. Results were validated by quantitative real-time (qRT-)PCR and in situ hybridization. A comparison of miRNA profiles revealed 29 miRNAs that were differentially expressed between TRU- and non-TRU adenocarcinoma types. Specifically, hsa-miR-494 and ebv-miR-BART19 were up regulated by > 5-fold, whereas hsa-miR-551b was down regulated by > 5-fold in the non-TRU relative to the TRU type. The miRNA signature was confirmed by qRT-PCR analysis using an independent set of paired adenocarcinoma (non-TRU-type, n = 21 and TRU-type, n = 12) and normal tissue samples. Non-TRU samples showed increased expression of miR-494 (p = 0.033) and ebv-miR-BART19 (p = 0.001) as compared to TRU-type samples. Both miRNAs were weakly expressed in the TRU type but strongly expressed in the non-TRU type. Neither subtype showed miR-551b expression. TRU- and non-TRU-type adenocarcinomas have distinct miRNA expression profiles, suggesting that tumorigenesis in lung adenocarcinoma occur via different pathways.

Recent guidelines recommend the use by healthcare personnel of a fit-tested N95 particulate respirator or higher-grade respiratory precaution in a patient undergoing bronchoscopy when pulmonary tuberculosis (PTB) is suspected. However, PTB may be unexpectedly diagnosed in this setting and therefore not evaluated, resulting in the unexpected exposure to Mycobacterium tuberculosis (MTB) of healthcare workers in the bronchoscopy suite. Here, we examined the incidence of unexpected exposure to MTB during flexible bronchoscopy and determined the exposure-related factors.Between 2011 and 2013, a retrospective study was conducted to evaluate unexpected diagnoses of PTB in the bronchoscopy suite. During the study period, 1650 consecutive patients for whom previous CT scans were available and who underwent bronchoscopy for respiratory disease other than PTB were included. The results of bronchial washing, bronchoalveolar lavage, and post-bronchoscopic sputum were reviewed.PTB was unexpectedly diagnosed in 76 patients (4.6%). The presence of anthracofibrosis [odds ratio (OR), 3.878; 95% confidence interval (CI), 1.291-11.650; P = 0.016), bronchiectasis (OR, 1.974; 95% CI, 1.095-3.557; P = 0.024), or atelectasis (OR, 1.740; 95% CI, 1.010-2.903; P = 0.046) as seen on chest CT scan was independently associated with unexpected PTB. Patients with both anthracofibrosis and atelectasis were at much higher risk of unexpected PTB (OR, 4.606; 95% CI, 1.383-15.342; P = 0.013).The risk of MTB exposure by healthcare personnel in the bronchoscopy suite due to patients with undiagnosed PTB has been underestimated. Therefore, in geographic regions with an intermediate PTB prevalence, such as South Korea (97/100,000 persons per year), higher-grade respiratory precaution, such as a fit-tested N95 particulate respirator, should be considered to prevent occupational exposure to MTB during routine bronchoscopy, especially in patients with CT-confirmed anthracofibrosis, bronchiectasis, or atelectasis.

The title of page 189 should be corrected.

Light emitting diode (LED) lights play an important role in the plant physiology and alter the metabolites in a significant manner. Glucosinolates (GSLs), polyphenols, flavonoids and antioxidant properties of Chinese cabbage and kale cultivated in varying LED lights were investigated. Analysis revealed 7 aliphatic, 3 indolyl and 1 aromatic GSLs in Chinese cabbage and kale. The total GSL content ranged from 1.5-19.08 and 1.85-24.87 µmol/g DW, and glucobrassicanapin was the predominant GSL (3) in Chinese cabbage, whereas; sinigrin (3.49 µmol/g DW) was in kale. Blue and red LED lights produced significantly higher amount of GSLs in Chinese cabbage and kale respectively. Results revealed higher amount of total polyphenol (3.845 µg/mL) and total flavanoids (3.939 μg/mL) in Chinese cabbage. Chinese cabbage and kale showed significant antioxidant activities when compare with positive control, and the antioxidant assays were slightly correlated with total GSLs, polyphenols and flavanoids contents. The influence of LED lights on glucobrassicin in Chinese cabbage and kale should be studied extensively, because GSL is the precursor of indole-3-carbinol, a potent anticancer isothiocyanate.