A prospective, open-label, randomized clinical trial to evaluate the efficacy and safety of remimazolam in patients undergoing EBUS-TBNA: REST trial design.

BACKGROUND: Remimazolam is safe and effective for moderate sedation during flexible bronchoscopy, but its safety and efficacy during endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) remains undetermined. The REST trial (NCT06275594) will be a prospective randomized study of remimazolam in patients undergoing EBUS-TBNA with conscious sedation. The primary aim is to evaluate whether remimazolam is safe and effective for moderate sedation during EBUS-TBNA compared to real-world midazolam and on-label midazolam. METHODS: The REST trial will recruit 330 patients from four university hospitals with mediastinal lesions suspected of being lung cancer who are eligible for EBUS-TBNA under moderate sedation. The participants will be randomized into groups using remimazolam, real-world midazolam, and on-label midazolam (US prescribing information dosage) to perform EBUS-TBNA for procedural sedation. The primary endpoint will be procedural success using composite measures. DISCUSSION: The REST trial will prospectively evaluate the efficacy and safety of remimazolam during EBUS-TBNA under moderate sedation. It will provide information for optimizing sedation modalities and contribute to practical benefits in patients undergoing EBUS-TBNA. TRIAL REGISTRATION: ClinicalTrials.gov (NCT06275594). Prospectively registered on 15 February 2024.

Impact of Respiratory Bacterial Findings on Patients with Chronic Pulmonary Aspergillosis.

Background: Distinct bacterial strains may affect the prognosis of patients with chronic respiratory diseases. However, little is known about the clinical significance of respiratory bacteria in patients with chronic pulmonary aspergillosis (CPA), a progressive and debilitating disease caused by Aspergillus spp. Objectives: This study aimed to analyze data obtained from CPA patients and their sputum or bronchial washing samples and investigate the prevalence and composition of respiratory bacteria and clinical implications. Patients and Methods. We retrospectively reviewed the data of patients diagnosed with CPA between March 2019 and February 2023 in a tertiary referral hospital. We assessed the clinical characteristics and overall and pneumonia-specific survival rates of patients with CPA based on the presence of bacteria. Results and Conclusions. We included 142 patients with CPA. The most commonly identified bacteria were Klebsiella pneumoniae (22.5%), followed by Pseudomonas aeruginosa (21.8%) and Escherichia coli (4.2%). Patients with isolated bacteria had a higher prevalence of older age, female sex, diabetes, and a history of extrathoracic malignancy than those without isolated bacteria (P = 0.024, 0.013, 0.021, and 0.034, respectively). Furthermore, over a median follow-up of 11 (4-21) months, the pneumonia-specific mortality rate was 13.4% (19/142), which was higher in patients with isolated bacteria than in those without (P = 0.045, log-rank test). Particularly, patients with the presence of P. aeruginosa had a significantly higher mortality rate from pneumonia than those without the presence of P. aeruginosa (adjusted hazard ratio, 3.34; P = 0.015). In conclusion, CPA patients with isolated bacteria, especially P. aeruginosa, showed higher mortality rates due to pneumonia. Performing tests to identify bacteria in the lower respiratory tract of patients with CPA may be helpful in predicting future prognosis. Further studies are required to validate these findings in diverse ethnic groups.

Increased Lung Cancer Risk and Associated Risk Factors in Tuberculosis Survivors: A Korean Population-Based Study.

BACKGROUND: Few studies have comprehensively evaluated the risk of lung cancer in tuberculosis survivors with consideration of smoking status and chronic obstructive pulmonary disease (COPD). Furthermore, little is known about lung cancer risk factors in tuberculosis survivors. METHODS: This population-based cohort study enrolled tuberculosis survivors (n = 75 467) between 2010 and 2017 and 1:1 age- and sex-matched controls. Subjects were followed up for 1 year from the date of tuberculosis diagnosis to the date of the incident lung cancer, death, or December 2018, whichever came first. The risk of lung cancer was evaluated according to smoking and COPD status. We also evaluated the risk factors for lung cancer and developed an individualized lung cancer prediction model for tuberculosis survivors. RESULTS: During a median follow-up duration of 4.8 years, the incident lung cancer risk was 1.72-fold higher in tuberculosis survivors than in the controls. Among tuberculosis survivors, those who were current smokers with ≥20 pack-years showed the highest risk of lung cancer (adjusted hazard ratio, 6.78) compared with never-smoker, non-tuberculosis-infected controls. tuberculosis survivors with COPD had a higher risk (2.43) than non-COPD, non-tuberculosis-infected controls. Risk factors for lung cancer in tuberculosis survivors were pulmonary tuberculosis, age >60 years, smoking, and the presence of COPD or asthma. The individualized lung cancer risk model showed good discrimination (concordance statistic = 0.827). CONCLUSIONS: Previous tuberculosis infection is an independent risk factor regardless of smoking status or amount and COPD. Closer monitoring of tuberculosis survivors, especially heavy smokers or those with COPD, is needed for early lung cancer diagnosis.

Clinical characteristics and drug resistance profile of patients with endobronchial tuberculosis in South Korea: single-center experience.

BACKGROUND: Tuberculosis (TB) is a major infectious disease worldwide; there has been a significant increase in the number of elderly patients with TB, largely contributing to TB-related mortality. Although endobronchial tuberculosis (EBTB) is a unique form of pulmonary TB, available data on the clinical characteristics and drug susceptibility (DST) patterns of patients with EBTB are scarce. METHODS: We evaluated the clinical characteristics of patients with EBTB in South Korea and the culture-based DST patterns of EBTB. Further, the DST patterns were compared between elderly (≥65 years) and young (<65 years) patients. We retrospectively reviewed data of patients with EBTB who had the results of DST and were diagnosed between January 2013 and December 2019 at a tertiary referral hospital in South Korea. Phenotypic DST of 15 first-line and second-line anti-TB drugs was performed using Mycobacterium tuberculosis isolates prior to treatment. RESULTS: Of the 230 patients with EBTB, 69% were in elderly patients (≥65 years). Any-resistance occurred in 24 patients (10.4%), while multi-drug resistance (MDR) and extensive drug resistance (XDR) were observed in six patients (2.6%). Compared to that of the elderly treatment-naïve patients, previously treated elderly patients had a significantly higher proportion of resistance to rifampin (14.3% vs. 2.2%; P=0.031), ethambutol (9.5% vs. 0.7%; P=0.046), and pyrazinamide (9.5% vs. 0.7%; P=0.046). Further, MDR/XDR was observed more frequently in the previously treated elderly patients than that in the treatment-naïve elderly patients (14.3% vs. 1.4%; P=0.017). A relatively small number of drug-resistant cases (5.6%) were observed in young patients. CONCLUSIONS: Elderly EBTB patients with previous Anti-tuberculous medications had a significantly higher proportion of drug-resistant TB. These patients should be carefully assessed using DST analysis before treatment.

Impacts of Asthma in Patients With Bronchiectasis: Findings From the KMBARC Registry.

PURPOSE: Although the coexistence of asthma and bronchiectasis is common, the impacts of asthma on bronchiectastic patients (BE) have not been well evaluated because this issue using bronchiectasis cohorts has been investigated in only a few studies. METHODS: In the present study, 598 patients who were prospectively enrolled in the Korean bronchiectasis registry were evaluated. The clinical characteristics between BE with asthma and those without asthma were compared. RESULTS: Asthma was found in 22.4% of BE. BE with asthma had a higher body mass index (BMI) (P = 0.020), more dyspnea (P < 0.001), larger sputum volume (P = 0.015), and lower forced expiratory volume in 1 second (FEV1) (P < 0.001) than those without asthma. BE with asthma had a higher rate of previous pneumonia (P = 0.017) or measles (P = 0.037) than those without asthma. Regarding treatment, BE with asthma used inhaled corticosteroids, long-acting muscarinic antagonists, and leukotriene receptor antagonists more frequently than those without asthma. Although intergroup differences were not observed in disease severity of bronchiectasis (P = 0.230 for Bronchiectasis Severity Index and P = 0.089 for FACED), the Bronchiectasis Health Questionnaire (BHQ) scores indicating the quality of life, were significantly lower in BE with asthma than in those without asthma (61.6 vs. 64.8, P < 0.001). In a multivariable model adjusting for age, sex, body mass index, forced expiratory volume in 1 second %predicted, sputum volume, modified Medical Research Council dyspnea scale ≥ 2, and the number of involved lobes, asthma was associated with lower BHQ scores (ß-coefficient = -2.579, P = 0.014). CONCLUSIONS: BE with asthma have more respiratory symptoms, worse lung function, and poorer quality of life than those without asthma. A better understanding of the impacts of asthma in BE will guide appropriate management in this population.

Chronic cavitary pulmonary aspergillosis: Serial clinical and CT findings correlated with antifungal treatment and patient response.

BACKGROUND: Chronic cavitary pulmonary aspergillosis (CCPA) is the most common form of chronic pulmonary aspergillosis. OBJECTIVE: We hypothesise that by observing serial clinical and CT findings of CCPA patients with antifungal therapy, factors helping predict responses to antifungal therapy could be withdrawn. METHODS: A total of 31 patients with CCPA who received antifungal therapy for greater than six months and who had serial CT studies were included. Clinical finding analyses were performed at initial and last follow-up CT acquisition dates. Clinical characteristics and CT features were compared between clinically improving or stable and deteriorating groups. RESULTS: With antifungal therapy, neutrophil-to-lymphocyte ratio (2.66 vs. 5.12, p = .038) and serum albumin (4.40 vs. 3.85 g/dl, p = .013) and CRP (1.10 vs. 42.80 mg/L, p = .007) were different between two groups. With antifungal therapy, meaningful CT change, regardless of clinical response grouping, was decrease in cavity wall thickness (from 13.70 mm to 8.28 mm, p < .001). But baseline (p = .668) and follow-up (p = .278) cavity wall thickness was not different between two groups. In univariate analysis, initial maximum diameter of cavity (p = .028; HR [0.983], 95% CI [0.967-0.998]) and concurrent NTM infection (p = .030; HR [0.20], 95% CI [0.05-0.86]) were related factors for poor clinical response. CONCLUSIONS: With antifungal therapy, cavities demonstrate wall thinning. Of all clinical and radiological findings and their changes, initial large cavity size and concurrent presence of NTM infection are related factors to poor response to antifungal therapy.

Relationship between Resistance to Ethambutol and Rifampin and Clinical Outcomes in Mycobacterium avium Complex Pulmonary Disease.

We evaluated the associations between the in vitro activities of ethambutol and rifampin and clinical outcomes of Mycobacterium avium complex (MAC) pulmonary disease (PD). Among 158 patients with MAC-PD, there was no relationship between high MICs for ethambutol and/or rifampin and treatment failure for MAC-PD. Ethambutol and rifampin resistance was common among MAC isolates (rates of 87% and 59%, respectively), but mutations in embB, rpoB, and rpoC were rare, with detection in only 4% of the drug-resistant MAC isolates.

Clinical impact of forced vital capacity on exercise performance in patients with chronic obstructive pulmonary disease.

BACKGROUND: Forced vital capacity (FVC) has been suggested to be a good biomarker for decreased exercise performance in patients with chronic obstructive pulmonary disease (COPD). However, as FVC is highly correlated with forced expiratory volume in 1 second (FEV1), the relationship between FVC and exercise capacity should be assessed within the category of FEV1, i.e., COPD severity. However, this was not considered in previous studies. Thus, limited data are available on the association between reduced FVC and exercise capacity measured by 6-min walk distance (6MWD) based on COPD severity. METHODS: We performed a cross-sectional study using data from the Korean COPD Subgroup Study (KOCOSS) cohort. We evaluated 1,386 patients with moderate (n=895) and severe-to-very severe (n=491) COPD. Reduced FVC was defined as FVC <80% predicted and short 6MWD as <350 m. Multivariable logistic regression was used to evaluate the association between reduced FVC and short 6MWD. RESULTS: There were no significant differences in respiratory symptoms and quality of life between the patients with reduced FVC and those with preserved FVC. However, patients with reduced FVC had shorter 6MWD (30.5 cm in moderate and 34.5 cm in severe-to-very severe COPD) and higher BODE index scores than those with preserved FVC. The cubic spline model revealed 6MWD peaked around 93% predicted of FVC in moderate COPD, whereas FVC showed a positive association with 6MWD in severe-to-very severe COPD. Multivariable analyses showed that reduced FVC was significantly associated with short 6MWD in both moderate [adjusted odds ratio (aOR) =1.44, 95% confidence interval (CI): 1.03-2.02] and severe-to-very severe (adjusted OR =1.55, 95% CI: 1.01-2.40) COPD. CONCLUSIONS: Reduced FVC was significantly associated with shorter 6MWD in moderate-to-very severe COPD patients, suggesting that reduced FVC might be reflective of 6MWD-measured exercise capacity in moderate-to-very severe COPD.

Association between 16S rRNA gene mutations and susceptibility to amikacin in Mycobacterium avium Complex and Mycobacterium abscessus clinical isolates.

We evaluated the association between 16S rRNA gene (rrs) mutations and susceptibility in clinical isolates of amikacin-resistant nontuberculous mycobacteria (NTM) in NTM-pulmonary disease (PD) patients. Susceptibility was retested for 134 amikacin-resistant isolates (minimum inhibitory concentration [MIC] ≥ 64 µg/ml) from 86 patients. Amikacin resistance was reconfirmed in 102 NTM isolates from 62 patients with either Mycobacterium avium complex-PD (MAC-PD) (n = 54) or M. abscessus-PD (n = 8). MICs and rrs mutations were evaluated for 318 single colonies from these isolates. For the 54 MAC-PD patients, rrs mutations were present in 34 isolates (63%), comprising all 31 isolates with amikacin MICs ≥ 128 µg/ml, but only three of 23 isolates with an MIC = 64 µg/ml. For the eight M. abscessus-PD patients, all amikacin-resistant (MIC ≥ 64 µg/ml) isolates had rrs mutations. In amikacin-resistant isolates, the A1408G mutation (n = 29) was most common. Two novel mutations, C1496T and T1498A, were also identified. The culture conversion rate did not differ by amikacin MIC. Overall, all high-level and 13% (3/23) of low-level amikacin-resistant MAC isolates had rrs mutations whereas mutations were present in all amikacin-resistant M. abscessus isolates. These findings are valuable for managing MAC- and M. abscessus-PD and suggest the importance of phenotypic and genotypic susceptibility testing.

Translation and validation of the Korean version of the clinical frailty scale in older patients.

BACKGROUND: Frailty is a multidimensional syndrome that leads to an increase in vulnerability. Previous studies have suggested that frailty is associated with poor health-related outcomes. For frailty screening, the Clinical Frailty Scale (CFS) is a simple tool that is widely used in various translated versions. We aimed to translate the CSF into Korean and evaluated its contents and concurrent validity. METHODS: Translations and back-translations of the CFS were conducted independently. A multidisciplinary team decided the final CFS-K. Between August 2019 and April 2020, a total of 100 outpatient and inpatient participants aged ≥65 years were enrolled prospectively. The clinical characteristics were evaluated using the CFS-K. The CFS-K scores were compared with those of other frailty screening tools using Pearson's correlation coefficient and Spearman's rank correlation. The area under curve (AUC) for identifying the Eastern Cooperative Oncology Group Performance Status (ECOG PS) grade 3 or more was calculated for the CFS-K and other screening tools. RESULTS: The mean age of the participants was 76.5 years (standard deviation [SD], 7.0), and 63 (63%) participants were male. The mean CFS-K was 4.8 (SD, 2.5). Low body mass index (p = 0.013) and low score on the Korean version of the Mini-Mental State Examination (p < 0.001) were significantly associated with high CFS-K scores, except for those assigned to scale 9 (terminally ill). The CFS-K showed a significant correlation with other frailty screening tools (R = 0.7742-0.9190; p < 0.01), except in the case of those assigned to scale 9 (terminally ill). In comparison with other scales, the CFS-K identified ECOG PS grade 3 or more with the best performance (AUC = 0.99). Patients assigned to scale 9 on the CFS-K (terminally ill) had similar frailty scores to those assigned to scale 4 (vulnerable) or 5 (mildly frail). CONCLUSIONS: In conclusion, the CFS-K is a valid scale for measuring frailty in older Korean patients. The CFS-K scores were significantly correlated with the scores of other scales. To evaluate the predictive and prognostic value of this scale, further larger-scale studies in various clinical settings are warranted.

Comparative Study on the Effect of Cidofovir Treatment for Severe Adenovirus Pneumonia.

BACKGROUND: Adenovirus infection can cause severe pneumonia even in immunocompetent adults. However, there is limited data on the benefits of cidofovir treatment in severe adenovirus pneumonia. The objective of this study was to evaluate the association of cidofovir treatment with clinical improvement in immunocompetent adult patients with severe adenovirus pneumonia. METHODS: We evaluated 22 male patients who admitted to intensive care unit (ICU) with severe adenovirus pneumonia between January 2014 and December 2019. The patients were divided into 2 groups, patients treated with cidofovir or not. Clinical outcomes including time to defervescence and stopping of oxygen supplement, length of stay in ICU and hospital, and the need for mechanical ventilation (MV) and extracorporeal membrane oxygenation (ECMO) were compared between the 2 groups. RESULTS: Among 22 patients, 13 patients (59%) were treated with cidofovir and 9 (41%) were not. The difference in mean time (95% confidence interval [CI]) to defervescence and stopping of oxygen supplement between cidofovir group and no cidofovir group was 2.1 (-5.7 to 10.0) and 1.0 (-14.9 to 16.8) days, respectively. The difference in mean length of stay (95% CI) in ICU and hospital between the 2 groups was 0.2 (-7.1 to 7.5) and -0.4 (-18.3 to 17.5) days, respectively. The differences in proportion of patients requiring MV and ECMO between the 2 groups was 28.2 (-17.4 to 73.8) % and -10.3 (-52.2 to 31.7) %, respectively. CONCLUSIONS: The treatment with cidofovir for severe adenovirus pneumonia in immunocompetent patients did not improve clinical outcomes. Further studies with larger samples with prospective design are warranted.

Clinical Utility of Combined Circulating Tumor Cell and Circulating Tumor DNA Assays for Diagnosis of Primary Lung Cancer.

BACKGROUND/AIM: Although it has been suggested that circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) might be used in a complementary manner in lung cancer diagnosis, limited confirmatory data are available. In this prospective study, we evaluated the diagnostic performance of each assay separately and in combination. PATIENTS AND METHODS: From March 2018 to January 2019, patients with suspected primary lung cancer, who underwent routine lung cancer work-up and peripheral blood sampling, were prospectively enrolled in the study. Epithelial cell adhesion molecule and cytokeratin served as markers of CTCs. In terms of ctDNA analysis, single-nucleotide variants were evaluated via next-generation sequencing. RESULTS: We analyzed 111 patients, including 99 with primary lung cancer and 12 with benign pulmonary disease. The median number of CTCs in 10 ml of blood was 3. The most frequently detected single nucleotide variants of ctDNA were TP53, CDKN2A, and EGFR. The diagnostic sensitivity of conventional tumor marker (combination of carcinoembryonic antigen/CYFRA 21-1/neuron-specific enolase) was 66.7%, while those of the ctDNA and CTC assays were 72.7% and 65.7%, respectively. The sensitivity of the CTC/ctDNA combination (95.0%) was significantly greater than those of the CTC (p<0.001), ctDNA (p<0.001), or conventional tumor marker (p<0.001) alone. Subgroup analysis revealed that the sensitivity of the combination assay was greater than those of the CTC or ctDNA assays alone, regardless of tumor stage or histopathology type. CONCLUSION: The CTC/ctDNA combination assay enhanced the sensitivity of primary lung cancer diagnosis. The combination assay strategy may be clinically useful and could enhance the early detection of lung cancer (ClinicalTrials.gov number: NCT03479099).

miRNA Expression Profiles and Potential as Biomarkers in Nontuberculous Mycobacterial Pulmonary Disease.

Pulmonary disease (PD) due to nontuberculous mycobacteria (NTM) is increasing globally, but specific biomarkers for NTM-PD have not been established. As circulating miRNAs are promising biomarkers for various diseases, we investigated whether miRNAs have potential as NTM-PD biomarkers. Sera from 12 NTM-PD patients due to Mycobacterium avium, M. intracellulare, M. abscessus, or M. massiliense and three healthy controls were initially evaluated via small RNA sequencing. Multiple miRNAs showed significant differences in expression in patients compared to in healthy controls, with some expression differences unique to PD caused by a specific mycobacterial species. Notably, 14 miRNAs exhibited significant expression differences in PD associated with all four mycobacteria. Validation by quantitative reverse-transcription-PCR in an additional 40 patients with NTM-PD and 40 healthy controls confirmed that four differentially expressed miRNAs (hsa-miR-484, hsa-miR-584-5p, hsa-miR-625-3p, and hsa-miR-4732-5p) showed significantly higher serum expressions in NTM-PD patients than in controls. Receiver operating characteristic curve analysis of these four miRNAs supported the discriminative potential for NTM-PD and their combination provided an improved diagnostic value for NTM-PD. Furthermore, bioinformatics analysis revealed their 125 target genes, which were mostly associated with immune responses. Collectively, this study identified four miRNAs as potential biomarkers for NTM-PD and provided insight into NTM-PD pathophysiology.

Prognostic factors associated with long-term mortality in 1445 patients with nontuberculous mycobacterial pulmonary disease: a 15-year follow-up study.

Limited data are available regarding the prognostic factors for patients with nontuberculous mycobacterial pulmonary disease (NTM-PD). We investigated the prognostic factors associated with long-term mortality in NTM-PD patients after adjusting for individual confounders, including aetiological organism and radiological form.A total of 1445 patients with treatment-naïve NTM-PD who were newly diagnosed between July 1997 and December 2013 were included. The aetiological organisms were as follows: Mycobacterium avium (n=655), M. intracellulare (n=487), M. abscessus (n=129) and M. massiliense (n=174). The factors associated with mortality in NTM-PD patients were analysed using a multivariable Cox model after adjusting for demographic, radiological and aetiological data.The overall 5-, 10- and 15-year cumulative mortality rates for the NTM-PD patients were 12.4%, 24.0% and 36.4%, respectively. On multivariable analysis, the following factors were significantly associated with mortality in NTM-PD patients: old age, male sex, low body mass index, chronic pulmonary aspergillosis, pulmonary or extrapulmonary malignancy, chronic heart or liver disease and erythrocyte sedimentation rate. The aetiological organism was also significantly associated with mortality: M. intracellulare had an adjusted hazard ratio (aHR) of 1.40, 95% CI 1.03-1.91; M. abscessus had an aHR of 2.19, 95% CI 1.36-3.51; and M. massiliense had an aHR of 0.99, 95% CI 0.61-1.64, compared to M. avium Mortality was also significantly associated with the radiological form of NTM-PD for the cavitary nodular bronchiectatic form (aHR 1.70, 95% CI 1.12-2.59) and the fibrocavitary form (aHR 2.12, 95% CI 1.57-3.08), compared to the non-cavitary nodular bronchiectatic form.Long-term mortality in patients with NTM-PD was significantly associated with the aetiological NTM organism, cavitary disease and certain demographic characteristics.

Intermittent Treatment with Azithromycin and Ethambutol for Noncavitary Mycobacterium avium Complex Pulmonary Disease.

We evaluated the efficacy of intermittent azithromycin and ethambutol therapy for noncavitary Mycobacterium avium complex pulmonary disease (MAC-PD). Twenty-nine (76%) of 38 patients achieved sputum culture conversion after 12 months of treatment, and sputum smear positivity was an independent factor for failure to achieve culture conversion (adjusted odds ratio, 26.7; 95% confidence interval, 2.1 to 339.9; P = 0.011). Intermittent azithromycin and ethambutol may be an optional treatment regimen for noncavitary MAC-PD.

Computed tomographic findings of macrolide-resistant Mycobacterium massiliense pulmonary disease and changes after antibiotic treatment.

The purpose of this study was to present the computed tomographic (CT) findings of lung abnormalities in macrolide-resistant Mycobacterium massiliense pulmonary disease and its changes in follow-up CT after antibiotic treatment.Chest CT scans of patients with macrolide-resistant M massiliense pulmonary disease (n = 19) were retrospectively reviewed. Patients were treated with multidrug therapy, and sputum examinations were performed. Follow-up CT scans obtained during antibiotic treatment after detection of macrolide resistance were also reviewed, if available (n = 13). The CT scores at detection of macrolide resistance and at the last follow-up periods were also compared.Of all patients with macrolide-resistant M massiliense pulmonary disease, 2 (11%) patients achieved sputum culture conversion during the follow-up period. The most common CT findings of M massiliense pulmonary disease at detection of macrolide resistance were bronchiectasis and bronchiolitis (n = 19, 100%), followed by consolidation (n = 16, 84%), cavities (n = 11, 58%), and nodules (n = 6, 32%). On the last follow-up CT, overall CT scores were increased in 8 (62%) of 13 patients, and total mean CT score was significantly increased (P = .021). For each CT pattern, the cavity showed the greatest increase in CT score (P = .027), followed by bronchiectasis (P = .038).Common CT findings of macrolide-resistant M massiliense pulmonary disease were similar to those of pulmonary disease caused by other species of nontuberculous mycobacteria at presentation. However, in macrolide-resistant M massiliense pulmonary disease, serial CT scans showed deterioration with cavitary and bronchiectatic change in most patients despite multidrug antibiotic therapy.

Diagnostic Performance of Radial Probe Endobronchial Ultrasound without a Guide-Sheath and the Feasibility of Molecular Analysis.

BACKGROUND: Radial probe endobronchial ultrasound (R-EBUS), is effective for tissue diagnosis of lung lesions. We evaluated the diagnostic performance of R-EBUS both a guide-sheath and fluoroscopy and identified factors associated with accurate diagnosis. The feasibility of molecular and genetic testing, using specimens obtained by R-EBUS, was also investigated. METHODS: The study retrospectively reviewed 211 patients undergoing R-EBUS without a guide-sheath and fluoroscopy, June 2016-May 2017. After excluding 27 patients of which the target lesion was not reached, 184 were finally included. Multivariate logistic regression was used, to identify factors associated with accurate diagnosis. RESULTS: Among 184 patients, R-EBUS-guided biopsy diagnosed malignancy in 109 patients (59%). The remaining 75 patients (41%) with non-malignant results underwent additional work-ups, and 34 were diagnosed with malignancy. Based on final diagnosis, diagnostic accuracy was 80% (136/170), and sensitivity and specificity for malignancy were 76% (109/143) and 100% (27/27), respectively. In multivariate analysis, peripheral location (adjusted odds ratio [aOR], 3.925; 95% confidence interval [CI], 1.203-12.811; p=0.023), and central position of the probe (aOR, 2.435; 95% CI, 1.424-7.013; p=0.035), were associated with accurate diagnosis of malignancy. Molecular and genetic analyses were successful, in all but one case, with inadequate specimens. CONCLUSION: R-EBUS-guided biopsy without equipment, is effective for tissue diagnosis. Peripheral location and central position of the radial probe, were crucial for accurate diagnosis. Performance of molecular and genetic testing, using samples obtained by R-EBUS, was satisfactory.

In Vitro Activity of Bedaquiline and Delamanid against Nontuberculous Mycobacteria, Including Macrolide-Resistant Clinical Isolates.

We evaluated the in vitro activities of the antimicrobial drugs bedaquiline and delamanid against the major pathogenic nontuberculous mycobacteria (NTM). Delamanid showed high MIC values for all NTM except Mycobacterium kansasii However, bedaquiline showed low MIC values for the major pathogenic NTM, including Mycobacterium avium complex, Mycobacterium abscessus subsp. abscessus, M. abscessus subsp. massiliense, and M. kansasii Bedaquiline also had low MIC values with macrolide-resistant NTM strains and warrants further investigation as a potential antibiotic for NTM treatment.

Long-term natural history of non-cavitary nodular bronchiectatic nontuberculous mycobacterial pulmonary disease.

BACKGROUND: Information about the natural history of nontuberculous mycobacterial pulmonary disease (NTM-PD) is limited. The purpose of this study was to evaluate the long-term natural history of non-cavitary nodular bronchiectatic NTM-PD and the factors associated with treatment initiation and the frequency of spontaneous sputum culture conversion after diagnosis of NTM-PD. METHODS: We evaluated 1,021 patients with newly diagnosed non-cavitary nodular bronchiectatic NTM-PD caused by Mycobacterium avium complex or M. abscessus between 2003 and 2013. RESULTS: Of 1,021 patients, 562 (55%) initiated antibiotic treatment and 459 (45%) did not. Young age (adjusted hazard ratio [aHR] = 0.99; 95% confidence interval [CI] = 0.98-0.99), low body mass index (aHR = 0.96; 95% CI = 0.93-0.99), previous history of tuberculosis (aHR = 1.23; 95% CI = 1.01-1.50), respiratory complaints such as cough (aHR = 1.36; 95% CI = 1.05-1.75) and sputum production (aHR = 1.47; 95% CI = 1.13-1.91), and high number of involved lobes on high-resolution computed tomography (aHR = 1.22; 95% CI = 1.14-1.31) were associated with treatment initiation. Of 459 patients who did not initiate treatment, 157 (34%) showed spontaneous sputum culture conversion. None of the clinical factors was associated with spontaneous conversion. After spontaneous culture conversion, 26 of 157 (17%) showed redeveloped NTM-PD caused by a species different from the original species. CONCLUSIONS: The natural history of non-cavitary nodular bronchiectatic NTM-PD is variable. After diagnosis, the decision to initiate antibiotic therapy should be individualized based on consideration of the risk factors for disease progression. However, for patients who do not start antibiotic therapy, continuous and lifetime follow-up is recommended to manage underlying bronchiectasis and the possibility of late progression of NTM-PD.

Species Distribution and Macrolide Susceptibility of Mycobacterium fortuitum Complex Clinical Isolates.

The understanding of species distribution and inducible macrolide resistance in the Mycobacterium fortuitum complex (MFC) is limited. Of 90 mostly respiratory MFC clinical isolates, half were M. fortuitum, followed by M. peregrinum, M. porcinum, M. septicum, and M. conceptionense Most M. fortuitum, M. porcinum, and M. septicum isolates were inducibly resistant to clarithromycin, whereas two-thirds of the M. peregrinum isolates were clarithromycin susceptible. Clarithromycin-resistant M. fortuitum isolates exhibited common mutations of erm(39), potentially involved in clarithromycin resistance.