Improvement in Health-Related Quality of Life Following Antibiotic Treatment in Nontuberculous Mycobacterial Pulmonary Disease: Initial Analysis of the NTM-KOREA Cohort

BACKGROUND

Improving health-related quality of life (HRQOL) has emerged as a priority in the management of nontuberculous mycobacterial pulmonary disease (NTM-PD). We aimed to evaluate HRQOL and its changes after 6 months' treatment in patients with NTM-PD.

METHODS

The NTM-KOREA is a nationwide prospective cohort enrolling patients initiating treatment for NTM-PD in 8 institutions across South Korea. We conducted the Quality of Life-Bronchiectasis (QOL-B) at 6-month intervals and evaluated baseline scores (higher scores indicate better quality of life) and changes after 6 months' treatment. Multivariate logistic regression was performed to identify factors associated with improvement in the QOL-B physical functioning and respiratory symptoms domains.

RESULTS

Between February 2022 and August 2023, 411 patients were included in the analysis. Baseline scores (95% confidence interval [CI]) for physical functioning and respiratory symptoms were 66.7 (46.7-86.7) and 81.5 (70.4-92.6), respectively. Among 228 patients who completed the QOL-B after 6 months' treatment, improvements in physical functioning and respiratory symptoms were observed in 61 (26.8%) and 71 (31.1%) patients, respectively. A lower score (adjusted odds ratio; 95% CI) for physical functioning (0.93; 0.91-0.96) and respiratory symptoms (0.92; 0.89-0.95) at treatment initiation was associated with a greater likelihood of physical functioning and respiratory symptom improvement, respectively; achieving culture conversion was not associated with improvement in physical functioning (0.62; 0.28-1.39) or respiratory symptoms (1.30; 0.62-2.74).

CONCLUSIONS

After 6 months of antibiotic treatment for NTM-PD, HRQOL improved in almost one-third, especially in patients with severe initial symptoms, regardless of culture conversion.

CLINICAL TRIALS REGISTRATION

ClinicalTrials.gov identifier: NCT03934034.

Rates and Risk Factors of Progression in Patients With Nontuberculous Mycobacterial Pulmonary Disease: Secondary Analysis of a Prospective Cohort Study

BACKGROUND

The clinical course of nontuberculous mycobacterial pulmonary disease (NTM-PD) is varied, and a watchful waiting management strategy is appropriate for a subset of patients. Understanding disease progression and risk factors for progression is essential for deciding on an appropriate follow-up strategy.

RESEARCH QUESTION

What is the rate of NTM-PD progression, and what are the predictors of progression?

STUDY DESIGN AND METHODS

Patients with NTM-PD who were enrolled in a prospective observational cohort study between July 1, 2011, and December 31, 2022, were included in this analysis. Clinical, bacterial, laboratory, and radiographic data were collected at enrollment and then regularly during follow-up. NTM-PD progression was defined as either the initiation of treatment or the clinician's intention to treat. The rate of progression was calculated and the predictors for progression were analyzed.

RESULTS

Of the 477 patients enrolled, NTM-PD progressed in 192 patients over a median follow-up of 5.4 years. The incidence of NTM-PD progression was 11.0 cases per 100 person-years (95% CI, 9.5-12.7 cases per 100 person-years). The proportion of patients experiencing disease progression was 21.4% at 1 year, 33.8% at 3 years, and 43.3% at 5 years. The final multivariable analysis model identified female sex (adjusted hazard ratio [aHR], 1.69; 95% CI, 1.19-2.39), elevated erythrocyte sedimentation rate (aHR, 1.79; 95% CI, 1.31-2.43), FEV1 % predicted (aHR, 0.89; 95% CI, 0.82-0.96), and the presence of a cavity (aHR, 2.78; 95% CI, 2.03-3.80) as predictors of progression.

INTERPRETATION

About half of patients with NTM-PD experienced progression during an observation period of > 5 years. Patients with risk factors for progression should be observed closely.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01616745; URL: www.

CLINICALTRIALS

gov.

Clinical course of nontuberculous mycobacterial pulmonary disease in patients with rheumatoid arthritis

OBJECTIVES

The impact of rheumatoid arthritis (RA) on nontuberculous mycobacterial pulmonary disease (NTM-PD) has not been well established. In this study, we investigated the clinical course of NTM-PD in patients with RA and the impact of RA on the prognosis of NTM-PD.

METHODS

We analyzed patients who developed NTM-PD after being diagnosed with RA from January 2004 to August 2023 at a tertiary referral hospital in South Korea. The patient's baseline characteristics, clinical course, and prognosis were evaluated. An optimal matching analysis was performed to measure the impact of RA on the risk of mortality.

RESULTS

During the study period, 18 patients with RA [median age, 68 years; interquartile range (IQR) 59-73; female, 88.9%] developed NTM-PD. The median interval between RA diagnosis and subsequent NTM-PD development was 14.8 years (IQR, 8.6-19.5). At a median of 30 months (IQR, 27-105) after NTM-PD diagnosis, 10 of 18 (55.6%) patients received anti-mycobacterial treatment for NTM-PD and 5 (50.0%) patients achieved microbiological cure. When matched to patients with NTM-PD but without RA, patients with both RA and NTM-PD had a higher risk of mortality (adjusted hazard ratio, 8.14; 95% confidence interval, 2.43-27.2).

CONCLUSION

NTM-PD occurring after RA is associated with a higher risk of mortality than NTM-PD in the absence of RA.

Genetic stability of Mycobacterium abscessus during antibiotic treatment

OBJECTIVES

Genetic changes in Mycobacterium abscessus during antibiotic treatment are not fully understood. This study aimed to investigate the genetic changes in M. abscessus in patients receiving antibiotic treatment, and their clinical implications.

METHODS

Pretreatment and 12-month post-treatment M. abscessus isolates were obtained from patients with M. abscessus pulmonary disease. Isolates from each time point were separated into six groups based on their distinctive morphological characteristics. Twenty-four isolates, comprising 12 from patient A exhibiting progressive disease and 12 from patient B demonstrating stable disease, underwent sequencing. Subsequently, minimal inhibitory concentrations (MICs) for the administered antibiotics were measured.

RESULTS

Persistent infection with a single strain was observed in patients A and B. During 12 months of treatment, MICs for administered drugs did not generally change over time in either patient and single nucleotide variations (SNV) associated with antimicrobial resistance (rrl, rrs, erm(41), gyrA, gyrB, whiB7 and hflX) were not mutated. Although not significant, 47 and 52 non-synonymous SNVs occurred in M. abscessus from patients A and B, respectively, and the accumulation of these SNVs differed in patients A and B, except for five SNVs. The most variable positions were within a probable NADH-dependent glutamate synthase gene and a putative YrbE family protein gene in patients A and B, respectively.

CONCLUSIONS

Persistent infections by a single strain of M. abscessus were observed in two patients with different clinical courses. Genetic changes in M. abscessus during antibiotic treatment were relatively stable in these patients.

CLINICAL TRIALS IDENTIFIER

NCT01616745 (ClinicalTrials.gov ID).

Metabolomic Characteristics of Nontuberculous Mycobacterial Pulmonary Disease

BACKGROUND

The therapeutic challenges posed by nontuberculous mycobacterial pulmonary disease (NTM-PD) contribute to an unmet medical need. In this study, we aimed to investigate NTM-PD-specific metabolic pathways using serum metabolomics to understand disease pathogenesis.

METHODS

Mass spectrometry-based untargeted metabolomic profiling of serum from patients with NTM-PD (n = 50), patients with bronchiectasis (n = 50), and healthy controls (n = 60) was performed. Selected metabolites were validated by an independent cohort and subjected to pathway analysis and classification modeling.

RESULTS

Leucine, tyrosine, inosine, proline, 5-oxoproline, and hypoxanthine levels increased in the NTM-PD group compared with the healthy control group. Furthermore, levels of antioxidant metabolites (ferulic acid, α-lipoic acid, biotin, and 2,8-phenazinediamine) decreased in patients with NTM-PD. These changes were associated with arginine- and proline-related metabolism, leading to generation of reactive oxygen species. Interestingly, the observed metabolic changes in the NTM-PD group overlapped with those in the bronchiectasis group.

CONCLUSION

In NTM-PD, 11 metabolites linked to increased oxidative stress were significantly altered from those in healthy controls. Our findings enhance a comprehensive understanding of NTM-PD pathogenesis and provide insights for novel treatment approaches.

Treatment Outcomes of Clofazimine-Containing Regimens in Severe Mycobacterium avium Complex Pulmonary Disease

Background

Clofazimine is suggested as a promising drug for the treatment of nontuberculous mycobacterial pulmonary disease. However, the role of clofazimine in severe Mycobacterium avium complex pulmonary disease (MAC-PD) remains unclear. In this study, we investigated the treatment outcomes of patients with severe MAC-PD treated with regimens containing clofazimine.

Methods

This study included patients diagnosed with severe MAC-PD at Seoul National University Hospital who underwent anti-mycobacterial treatment between 1 January 2011 and 31 December 2022. We assessed the rate of culture conversion within 6 months and microbiological cure in patients receiving clofazimine-containing regimens, considering the dose and duration of clofazimine administration.

Results

A total of 170 patients with severe MAC-PD, treated with regimens containing clofazimine, were included in the analysis. The median age of patients was 68 years (interquartile range, 59-75 years), with a female predominance (n = 114 [67.1%]). Cavities were identified in 121 patients (71.2%). Within 6 months, 77 patients (45.3%) achieved culture conversion, and 84 of 154 (54.6%) patients attained microbiological cure. The dose of clofazimine (100 mg vs 50 mg) was not associated with culture conversion (adjusted odds ratio [aOR], 0.64 [95% confidence interval {CI}, .29-1.42]) or microbiological cure (aOR, 1.21 [95% CI, .52-2.81]). The microbiological cure rate reached 71.0% when clofazimine was administered for 6-12 months, compared to 23.1% when administered for <6 months.

Conclusions

Clofazimine demonstrated a relatively favorable efficacy in severe MAC-PD, regardless of the maintenance dose. This effect was more pronounced when administered for a duration exceeding 6 months.

Post-treatment Radiographic Severity and Mortality in Mycobacterium avium Complex Pulmonary Disease

Rationale: Imaging studies are widely performed when treating Mycobacterium avium complex pulmonary disease (MAC-PD); however, the clinical significance of post-treatment radiographic change is unknown. Objectives: To determine whether a deep neural network trained with pulmonary tuberculosis could adequately score the radiographic severity of MAC-PD and then to examine relationships between post-treatment radiographic severity and its change from baseline and long-term prognosis. Methods: We retrospectively collected chest radiographs of adult patients with MAC-PD treated for ⩾6 months at baseline and at 3, 6, 9, and 12 months of treatment. We correlated the radiographic severity score generated by a deep neural network with visual and clinical severity as determined by radiologists and mycobacterial culture status, respectively. The associations between the score, improvement from baseline, and mortality were analyzed using Cox proportional hazards regression. Results: In total, 342 and 120 patients were included in the derivation and validation cohorts, respectively. The network's severity score correlated with radiologists' grading (Spearman coefficient, 0.40) and mycobacterial culture results (odds ratio, 1.02; 95% confidence interval [CI], 1.0-1.05). A significant decreasing trend in the severity score was observed over time (P < 0.001). A higher score at 12 months of treatment was independently associated with higher mortality (adjusted hazard ratio, 1.07; 95% CI, 1.03-1.10). Improvements in radiographic scores from baseline were associated with reduced mortality, regardless of culture conversion (adjusted hazard ratio, 0.42; 95% CI, 0.22-0.80). These findings were replicated in the validation cohort. Conclusions: Post-treatment radiographic severity and improvement from baseline in patients with MAC-PD were associated with long-term survival.

The Impact of Trehalose Dimycolate on the Clinical Course of Mycobacterium avium Complex Pulmonary Disease

Rationale The clinical implications of trehalose 6,6'-dimycolate (TDM) in nontuberculous mycobacterial pulmonary disease have not been studied. Objective To examine the presence of TDM in clinical isolates obtained from patients with Mycobacterium avium complex (MAC) pulmonary disease (PD) and its impact on disease severity and treatment outcomes. Methods We analyzed clinical isolates from patients diagnosed with MAC-PD at Seoul National University Hospital between January 1, 2019, and December 31, 2021. The lipids were extracted from clinical isolates obtained at the time of diagnosis using mass spectrometry. Mass peaks between 300 and 3,500 m/z were obtained, and the peak patterns of the total lipids were analyzed. Results TDMs were identified in clinical isolates from 176 out of 343 patients. Cavities were more prevalent in patients with TDM-negative isolates (19.8%) than in patients with TDM-positive isolates (10.2%) (P=0.015). The time to antibiotic treatment was shorter in patients with TDM-negative isolates (4 months, interquartile range [IQR] 2-10) than in patients with TDM-positive isolates (7 months, IQR 3-16, P=0.032). Patients with TDM-negative isolates had a significantly lower proportion of culture conversions (P=0.012). TDM was associated with higher likelihood of culture conversion (adjusted hazard ratio, 2.29; P=0.035). Conclusions TDM-negative isolates were linked to a higher occurrence of cavities, earlier initiation of treatment, and worse treatment outcome in MAC-PD patients.

Microbiological Cure at Treatment Completion Is Associated With Longer Survival in Patients With Mycobacterium avium Complex Pulmonary Disease

BACKGROUND

Morbidity and mortality from nontuberculous mycobacterial pulmonary disease (NTM-PD) are increasing. Mycobacterium avium complex (MAC) is the most common cause of NTM-PD. Microbiological outcomes are widely used as the primary end point of antimicrobial treatment, but their long-term impact on prognosis is uncertain.

RESEARCH QUESTION

Do patients who achieve microbiological cure at the end of treatment have longer survival than those who do not?

STUDY DESIGN AND METHODS

We retrospectively analyzed adult patients who met the diagnostic criteria for NTM-PD, were infected with MAC species, and were treated with a macrolide-based regimen for ≥ 12 months per guidelines between January 2008 and May 2021 at a tertiary referral center. Mycobacterial culture was performed during antimicrobial treatment to assess the microbiological outcome. Patients with three or more consecutive negative cultures collected ≥ 4 weeks apart and no positive cultures until treatment completion were considered to have achieved microbiological cure. To assess the impact of microbiological cure on all-cause mortality, we performed multivariable Cox proportional hazards regression analysis adjusted for age, sex, BMI, presence of cavitary lesions, erythrocyte sedimentation rate, and underlying comorbid conditions.

RESULTS

Among 382 patients enrolled, 236 (61.8%) achieved microbiological cure at completion of treatment. These patients were younger, had lower erythrocyte sedimentation rates, were less likely to use four or more drugs, and had shorter treatment duration than those who failed to achieve microbiological cure. During a median follow-up of 3.2 (first quartile to third quartile, 1.4-5.4) years after treatment completion, 53 patients died. Microbiological cure was significantly associated with reduced mortality after adjustment for major clinical factors (adjusted hazard ratio, 0.52; 95% CI, 0.28-0.94). The association between microbiological cure and mortality was maintained in a sensitivity analysis that included all patients treated < 12 months.

INTERPRETATION

Microbiological cure at completion of treatment is associated with longer survival in patients with MAC-PD.

Identifying patients with multidrug-resistant tuberculosis who may benefit from shorter durations of treatment

OBJECTIVE

Studying treatment duration for rifampicin-resistant and multidrug-resistant tuberculosis (MDR/RR-TB) using observational data is methodologically challenging. We aim to present a hypothesis generating approach to identify factors associated with shorter duration of treatment.

STUDY DESIGN AND SETTING

We conducted an individual patient data meta-analysis among MDR/RR-TB patients restricted to only those with successful treatment outcomes. Using multivariable linear regression, we estimated associations and their 95% confidence intervals (CI) between the outcome of individual deviation in treatment duration (in months) from the mean duration of their treatment site and patient characteristics, drug resistance, and treatments used.

RESULTS

Overall, 6702 patients with successful treatment outcomes from 84 treatment sites were included. We found that factors commonly associated with poor treatment outcomes were also associated with longer treatment durations, relative to the site mean duration. Use of bedaquiline was associated with a 0.51 (95% CI: 0.15, 0.87) month decrease in duration of treatment, which was consistent across subgroups, while MDR/RR-TB with fluoroquinolone resistance was associated with 0.78 (95% CI: 0.36, 1.21) months increase.

CONCLUSION

We describe a method to assess associations between clinical factors and treatment duration in observational studies of MDR/RR-TB patients, that may help identify patients who can benefit from shorter treatment.

Prognostic serum biomarkers in non-tuberculous mycobacterial pulmonary disease

Increased serum C-reactive protein (CRP) levels at the time of diagnosis predicted worse prognosis in patients with non-tuberculous mycobacterial pulmonary disease (NTM-PD). Approximately one-quarter of the patients with NTM-PD had higher than normal CRP levels, and this elevation led to a higher risk of death.

Ethical Issues Referred to Clinical Ethics Support at a University Hospital in Korea: Three-Year Experience After Enforcement of Life-Sustaining Treatment Decisions Act

BACKGROUND

Clinical ethics support is a form of preventive ethics aimed at mediating ethics-related conflicts and managing ethical issues arising in the healthcare setting. However, limited evidence exists regarding the specific ethical issues in clinical practice. This study aimed to explore the diverse ethical issues of cases referred to clinical ethics support after the new legislation on hospice palliative care and end-of-life decision-making was implemented in Korea in 2018.

METHODS

A retrospective study of cases referred to clinical ethics support at a university hospital in Korea from February 2018 to February 2021 was conducted. The ethical issues at the time of referral were analyzed via qualitative content analysis of the ethics consultation-related documents.

RESULTS

A total of 60 cases of 57 patients were included in the study, of whom 52.6% were men and 56.1% were older than 60 years of age. The majority of cases (80%) comprised patients from the intensive care unit. One-third of the patients were judged as being at the end-of-life stage. The most frequent ethical categories were identified as goals of care/treatment (78.3%), decision-making (75%), relationship (41.7%), and end-of-life issues (31.7%). More specifically, best interests (71.7%), benefits and burdens/harms (61.7%), refusal (53.3%), and surrogate decision-making (33.3%), followed by withholding or withdrawal (28.3%) were the most frequent ethical issues reported, which became diversified by year. In addition, the ethical issues appeared to differ by age group and judgment of the end-of-life stage.

CONCLUSION

The findings of this study expand the current understanding of the diverse ethical issues including decision-making and goals of care/treatment that have been referred to clinical ethics support since the enforcement of the new legislation in Korea. This study suggests a need for further research on the longitudinal exploration of ethical issues and implementation of clinical ethics support in multiple healthcare centers.

Impact of treatment on long-term survival of patients with Mycobacterium avium complex pulmonary disease

BACKGROUND

Whether antimicrobial treatment improves long-term survival in patients with Mycobacterium avium complex pulmonary disease (MAC-PD) is unclear.

METHODS

We analyzed survival of patients aged ≥18 years who were treated for MAC-PD at a tertiary referral center in South Korea between January 1, 2009 and December 31, 2020. Treatment exposure was divided into four-time intervals: <6 months, ≥6 to <12 months, ≥12 to <18 months, and ≥18 months. Time-varying multivariable Cox proportional hazards models were used to calculate the risk of all-cause mortality in each time interval. The model was adjusted for major clinical factors related to mortality including age, sex, body mass index, presence of cavities, erythrocyte sedimentation rate, positive acid-fast bacilli (AFB) smear, clarithromycin resistance, and comorbidities.

RESULTS

A total of 486 patients treated for MAC-PD were included in the analysis. A significant inverse correlation was observed between mortality and duration of treatment (P for trend = 0.007). Patients treated for ≥18 months were significantly associated with reduced mortality [adjusted hazard ratio (aHR) 0.32, 95% confidence interval (CI) 0.15-0.71]. In subgroup analyses, patients with cavitary lesions (aHR 0.17, 95% CI 0.05-0.57) or positive AFB smears (aHR 0.13, 95% CI 0.02-0.84) at baseline maintained this significant inverse relationship between treatment duration and mortality.

CONCLUSIONS

Long-term antimicrobial treatment should be actively considered in patients with progressive MAC-PD, especially in the presence of cavities or positive AFB smears indicative of high mycobacterial burden.

The Clinical Course and Prognosis of Patients With Nontuberculous Mycobacterial Pulmonary Disease After Solid Organ Transplantation

BACKGROUND

Due to impaired cell-mediated immunity, solid organ transplantation (SOT) recipients are at increased risk of developing nontuberculous mycobacterial pulmonary disease (NTM-PD). However, the clinical course of NTM-PD in SOT patients and the impact of SOT on the prognosis of NTM-PD remain unclear.

METHODS

We analyzed patients who developed NTM-PD after receiving SOT between January 2001 and December 2020, at a tertiary referral hospital in South Korea. Baseline characteristics, clinical course, and prognosis were evaluated. Propensity score-matched analysis was performed to assess the impact of SOT on long-term survival in patients with NTM-PD.

RESULTS

Among 4,685 SOT recipients over 20 years, 12 patients (median age, 64 years; interquartile range [IQR], 59-67 years; men, 66.7%) developed NTM-PD. Seven (58.3%) and five (41.7%) patients underwent kidney and liver transplantation, respectively, before the diagnosis of NTM-PD. The incidence of NTM-PD was 35.6 cases per 100,000 person-years among kidney transplant recipients and 28.7 cases per 100,000 person-years among liver transplant recipients. The median time between transplantation and the diagnosis of NTM-PD was 3.3 (IQR, 1.5-10.8) years. The most common mycobacterial species was Mycobacterium avium (50.0%). Antibiotic treatment was initiated in five (41.7%) patients, and two patients (40.0%) achieved microbiological cure. Two patients died during a median follow-up of 4.2 (IQR, 2.3-8.8) years and NTM-PD was assumed to be the cause of death in one patient. When matched to patients without a history of SOT, patients with a history of SOT did not show worse survival (P value for log-rank test = 0.62).

CONCLUSION

The clinical course of NTM-PD in SOT recipients was comparable to that of patients without SOT, and SOT did not increase the risk of all-cause mortality in patients with NTM-PD.

Mycobacterial cavity on chest computed tomography: clinical implications and deep learning-based automatic detection with quantification

Background

This study aimed (I) to investigate the clinical implication of computed tomography (CT) cavity volume in tuberculosis (TB) and non-tuberculous mycobacterial pulmonary disease (NTM-PD), and (II) to develop a three-dimensional (3D) nnU-Net model to automatically detect and quantify cavity volume on CT images.

Methods

We retrospectively included conveniently sampled 206 TB and 186 NTM-PD patients in a tertiary referral hospital, who underwent thin-section chest CT scans from 2012 through 2019. TB was microbiologically confirmed, and NTM-PD was diagnosed by 2007 Infectious Diseases Society of America/American Thoracic Society guideline. The reference cavities were semi-automatically segmented on CT images and a 3D nnU-Net model was built with 298 cases (240 cases for training, 20 for tuning, and 38 for internal validation). Receiver operating characteristic curves were used to evaluate the accuracy of the CT cavity volume for two clinically relevant parameters: sputum smear positivity in TB and treatment in NTM-PD. The sensitivity and false-positive rate were calculated to assess the cavity detection of nnU-Net using radiologist-detected cavities as references, and the intraclass correlation coefficient (ICC) between the reference and the U-Net-derived cavity volumes was analyzed.

Results

The mean CT cavity volumes in TB and NTM-PD patients were 11.3 and 16.4 cm³, respectively, and were significantly greater in smear-positive TB (P<0.001) and NTM-PD necessitating treatment (P=0.020). The CT cavity volume provided areas under the curve of 0.701 [95% confidence interval (CI): 0.620-0.782] for TB sputum positivity and 0.834 (95% CI: 0.773-0.894) for necessity of NTM-PD treatment. The nnU-Net provided per-patient sensitivity of 100% (19/19) and per-lesion sensitivity of 83.7% (41/49) in the validation dataset, with an average of 0.47 false-positive small cavities per patient (median volume, 0.26 cm³). The mean Dice similarity coefficient between the manually segmented cavities and the U-Net-derived cavities was 78.9. The ICCs between the reference and U-Net-derived volumes were 0.991 (95% CI: 0.983-0.995) and 0.933 (95% CI: 0.897-0.957) on a per-patient and per-lesion basis, respectively.

Conclusions

CT cavity volume was associated with sputum positivity in TB and necessity of treatment in NTM-PD. The 3D nnU-Net model could automatically detect and quantify mycobacterial cavities on chest CT, helping assess TB infectivity and initiate NTM-TB treatment.

The Rise in Prevalence and Related Costs of Nontuberculous Mycobacterial Diseases in South Korea, 2010-2021

Between 2010 and 2021, the annual prevalence of nontuberculous mycobacterial (NTM) diseases in South Korea increased from 11.4 to 56.7 cases per 100 000 population. Prevalence in the population aged ≥65 years quadrupled from 41.9 to 163.1 cases per 100 000 population. Accordingly, the overall cost associated with NTM diseases increased.

9 months of delamanid, linezolid, levofloxacin, and pyrazinamide versus conventional therapy for treatment of fluoroquinolone-sensitive multidrug-resistant tuberculosis (MDR-END): a multicentre, randomised, open-label phase 2/3 non-inferiority trial in South Korea

BACKGROUND

With the introduction of new anti-tuberculosis drugs, all-oral regimens with shorter treatment durations for multidrug-resistant tuberculosis have been anticipated. We aimed to investigate whether a new all-oral regimen was non-inferior to the conventional regimen including second-line anti-tuberculosis drugs for 20-24 months in the treatment of fluoroquinolone-sensitive multidrug-resistant tuberculosis.

METHODS

In this multicentre, randomised, open-label phase 2/3 non-inferiority trial, we enrolled men and women aged 19-85 years with multidrug-resistant tuberculosis confirmed by phenotypic or genotypic drug susceptibility tests or rifampicin-resistant tuberculosis by genotypic tests at 12 participating hospitals throughout South Korea. Participants with fluoroquinolone-resistant multidrug-resistant tuberculosis were excluded. Participants were randomly assigned (1:1) to two groups using a block randomisation, stratified by the presence of diabetes and cavitation on baseline chest radiographs. The investigational group received delamanid, linezolid, levofloxacin, and pyrazinamide for 9 months, and the control group received a conventional 20-24-month regimen, according to the 2014 WHO guidelines. The primary outcome was the treatment success rate at 24 months after treatment initiation in the modified intention-to-treat population and the per-protocol population. Participants who were "cured" and "treatment completed" were defined as treatment success following the 2014 WHO guidelines. Non-inferiority was confirmed if the lower limit of a 97·5% one-sided CI of the difference between the groups was greater than -10%. Safety data were collected for 24 months in participants who received a predefined regimen at least once. This study is registered with ClinicalTrials.gov, NCT02619994.

FINDINGS

Between March 4, 2016, and Sept 14, 2019, 214 participants were enrolled, 168 (78·5%) of whom were included in the modified intention-to-treat population. At 24 months after treatment initiation, 60 (70·6%) of 85 participants in the control group had treatment success, as did 54 (75·0%) of 72 participants in the shorter-regimen group (between-group difference 4·4% [97·5% one-sided CI -9·5% to ∞]), satisfying the predefined non-inferiority margin. No difference in safety outcomes was identified between the control group and the shorter-regimen group.

INTERPRETATION

9-month treatment with oral delamanid, linezolid, levofloxacin, and pyrazinamide could represent a new treatment option for participants with fluoroquinolone-sensitive multidrug-resistant tuberculosis.

FUNDING

Korea Disease Control and Prevention Agency, South Korea.

Outcomes of Adjunctive Surgery in Patients With Nontuberculous Mycobacterial Pulmonary Disease: A Systematic Review and Meta-analysis

BACKGROUND

The burden of nontuberculous mycobacterial pulmonary disease (NTM-PD) is increasing worldwide. Amidst the poor treatment success of antibiotic therapy, adjunctive surgery is gaining attention; however, discrepancies in reported outcomes exist.

RESEARCH QUESTION

What are the treatment outcomes and complications of patients with NTM-PD undergoing adjunctive surgery?

STUDY DESIGN AND METHODS

The MEDLINE, Embase, and Cochrane databases were searched for eligible studies before January 2022. Studies reporting the outcomes of adjunctive surgery in adult patients who satisfied the diagnostic criteria for NTM-PD were included. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guidelines. Data were extracted by two independent observers. Estimates of proportion were pooled using a random-effects model. Sputum mycobacterial culture negative conversion, recurrence, complications, and in-hospital mortality after surgery were primary outcomes that had been set before data collection began. Heterogeneity was evaluated by using the I² statistic, and publication bias was assessed by using funnel plots and the Egger test.

RESULTS

Fifteen of the 2,739 screened studies, with 1,071 patients, were assessed. The weighted proportion of postoperative sputum culture negative conversion was 93% (95% CI, 87%-97%), and recurrence was 9% (95% CI, 6%-14%) for a median follow-up of 34 months. The proportion of patients who experienced postoperative complications was 17% (95% CI, 13%-23%), and in-hospital mortality was 0% (95% CI, 0%-2%). Studies that performed multilobar lung resection in > 30% of the study population showed comparable rates of complications with studies that did not.

INTERPRETATION

Adjunctive surgery is an effective therapeutic option with acceptable rates of complications for selected patients with NTM-PD.

TRIAL REGISTRY

PROSPERO; No.: CRD42022310663; URL: https://www.crd.york.ac.uk/prospero/.

Pulmonary function and chest computed tomography abnormalities 6-12 months after recovery from COVID-19: a systematic review and meta-analysis

Background

Some coronavirus disease 2019 (COVID-19) survivors experience prolonged and varying symptoms, a condition termed post-acute COVID-19 syndrome (PACS). However, the prevalence of chronic pulmonary sequelae of PACS during long-term follow-up remains unclear. Several studies have examined this issue and reported heterogeneous results.

Methods

We conducted a systematic review and meta-analysis using a random-effects model to estimate the pooled prevalence of the pulmonary sequelae of COVID-19, as demonstrated by pulmonary function testing (PFT) and chest computed tomography (CT) performed at least 6 months after initial infection. PubMed, Embase, and Cochrane Library databases were searched from January 1, 2020 to December 31, 2021 to identify related studies. We investigated whether the prevalence of pulmonary sequelae decreased over time and attempted to identify the factors associated with their development by performing multiple subgroup and meta-regression analyses.

Results

Of the 18,062 studies identified, 30 met our eligibility criteria. Among these studies, 25 and 22 had follow-up PFT and chest CT data, respectively. The follow-up durations were approximately 6 and 12 months in 18 and 12 studies, respectively. Impaired diffusion capacity was the most common abnormality on PFT (pooled prevalence 35%, 95% confidence interval [CI] 30–41%) with a prevalence of 39% (95% CI 34–45%) and 31% (95% CI 21–40%) in the 6-month and 12-month follow-up studies, respectively (P = 0.115). Restrictive pulmonary dysfunction evident as reduced forced vital capacity was less frequent (pooled prevalence 8%, 95% CI 6–11%); however, its prevalence was lower in the 12-month follow-up studies than in the 6-month follow-up studies (5% [95% CI 3–7%] vs. 13% [95% CI 8–19%], P = 0.006). On follow-up chest CT, the pooled prevalence of persistent ground-glass opacities and pulmonary fibrosis was 34% (95% CI 24–44%) and 32% (95% CI 23–40%), respectively, and the prevalence did not decrease over time. As every meta-analysis showed significant between-study heterogeneity, subgroup and meta-regression analyses were performed to identify potential effect modifiers; the severity of index infection was associated with the prevalence of impaired diffusion capacity and pulmonary fibrosis.

Conclusions

A substantial number of COVID-19 survivors displayed pulmonary sequelae as part of PACS. Except for restrictive pulmonary dysfunction, the prevalence of these sequelae did not decrease until 1 year after initial infection. Considering the association between the severity of acute COVID-19 and risk of pulmonary sequelae, patients who recover from severe COVID-19 require close respiratory follow-up.

Systematic review registration number PROSPERO CRD42021234357

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02163-x.

How to enhance students' learning in a patient-centered longitudinal integrated clerkship: factors associated with students' learning experiences

PURPOSE

Longitudinal integrated clerkships (LICs) have been introduced in medical schools, as learning relationships with clinical faculty or peers are important components of medical education. The purpose of this study was to investigate the characteristics of student-faculty and student-student interactions in the LIC and to identify other factors related to whether students understood and acquired the program's main outcomes.

METHODS

The study was conducted among the 149 third-year students who participated in the LIC in 2019. We divided the students into groups of eight. These groups were organized into corresponding discussion classes, during which students had discussions with clinical faculty members and peers and received feedback. Clinical faculty members and students were matched through an e-portfolio, where records were approved and feedback was given. A course evaluation questionnaire was completed and analysed.

RESULTS

A total of 144 valid questionnaires were returned. Logistic regression analysis showed that relevant feedback in discussion classes (adjusted odds ratio [AOR], 5.071; p<0.001), frequency of e-portfolio feedback (AOR, 1.813; p=0.012), and motivation by e-portfolio feedback (AOR, 1.790; p=0.026) predicted a greater likelihood of understanding the continuity of the patient's medical experience. Relevant feedback from faculty members in discussion classes (AOR, 3.455; p<0.001) and frequency of e-portfolio feedback (AOR, 2.232; p<0.001) also predicted a greater likelihood of understanding the concept of patient-centered care.

CONCLUSION

Student-faculty interactions, including relevant feedback in discusstion classes, frequency of e-portfolio feedback, and motivation by e-portfolio feedback were found to be important factors in the LIC program.

Treatment shortening of drug-sensitive pulmonary tuberculosis using high-dose rifampicin for 3 months after culture conversion (Hi-DoRi-3): a study protocol for an open-label randomized clinical trial

BACKGROUND

The standard treatment regimen for drug-sensitive tuberculosis (TB), comprising four companion drugs, requires a minimum duration of 6 months, and this lengthy treatment leads to poor adherence and increased toxicity. To improve rates of adherence, reduce adverse events, and lower costs, a simplified and shortened treatment regimen is warranted.

METHODS

This study is a multicenter, open-label randomized clinical trial of non-inferiority design that compares a new regimen with the conventional regimen for drug-sensitive pulmonary TB. The investigational group will use a regimen of high-dose rifampicin (30 mg/kg/day) with isoniazid and pyrazinamide, and the treatment will be maintained for 12 weeks after the achievement of negative conversion of sputum culture. The control group will be treated for 6 months with a World Health Organization-endorsed regimen consisting of isoniazid, rifampicin (10 mg/kg/day), ethambutol, and pyrazinamide. The primary endpoint is the proportion of unfavorable outcomes at 18 months after randomization. Secondary outcomes include time to unfavorable treatment outcome, time to culture conversion on liquid medium, treatment success rate at the end of treatment, proportion of recurrence at 18 months after randomization, time to recurrence after treatment completion, and adverse events of grade 3 or higher during the treatment. We predict a 10% unfavorable outcome for the control group, and 0% difference from the investigational group. Based on 80% verification power and a 2.5% one-sided significance level for a non-inferiority margin of 6%, 393 participants per group are required. Considering the 15% dropout rate, a total of 926 participants (463 in each group) will be recruited.

DISCUSSION

This study will inform on the feasibility of the treatment regimen using high-dose rifampicin with a shortened and individualized treatment duration for pulmonary TB.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04485156 . Registered on July 24, 2020.

Old age is associated with worse treatment outcome and frequent adverse drug reaction in Mycobacterium avium complex pulmonary disease

Background

The number of patients with nontuberculous mycobacterial pulmonary disease (NTM-PD) is rapidly increasing globally, especially in the older population. However, there is a dearth of evidence regarding the impact of aging on the treatment outcomes of NTM-PD.

Methods

We analyzed consecutive patients who satisfied the diagnostic criteria for Mycobacterium avium complex (MAC)-PD and received antibiotic treatment between January 2009 and December 2020 at a tertiary referral hospital in Korea. The main outcomes were (1) long-term treatment success, defined by negative culture conversion for more than 12 months; and (2) adverse drug reactions (ADRs). Multivariable logistic regression model was used to evaluate the association between age and main outcomes.

Results

A total of 614 patients (median age, 65 years, interquartile range [IQR] 57–73 years; men, 35.3%) were included. Median treatment duration (530 days, IQR 290–678 days; P for trend < 0.001) and long-term treatment success (P for trend = 0.026) decreased, whereas ADRs (P for trend < 0.001) increased significantly with age. Multivariable analyses demonstrated that age ≥ 80 years was an independent factor associated with ADRs (adjusted odds ratio [aOR] 3.29; 95% confidence interval [CI] 1.05–10.28) and worse treatment outcome (aOR 0.42; 95% CI 0.19–0.91).

Conclusions

Aging is associated with worse treatment outcome and frequent ADRs of patients with MAC-PD. Individualized treatment with reduced-intensity may be a reasonable alternative for older adults.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02063-2.

CT and 18F-FDG PET abnormalities in contacts with recent tuberculosis infections but negative chest X-ray

Close contacts of individuals with pulmonary tuberculosis are at risk for tuberculosis infection and the development of active tuberculosis. In current contact investigations, immunologic tests (the tuberculin skin test and interferon-gamma release assay) and chest X-ray examinations are used to dichotomize contacts with Mycobacterium tuberculosis infections into those with active (X-ray abnormalities) versus latent tuberculosis (normal radiographs). This article is a critical review of computed tomographic (CT) and 18-fluorodeoxyglucose positron emission tomographic (PET) findings of incipient tuberculosis without X-ray abnormalities based on a systematic literature review of twenty-five publications. The CT and 18-fluorodeoxyglucose PET studies revealed minimal pauci-nodular infiltrations in the lung parenchyma and mediastinal lymph nodes abnormalities with metabolic uptake in approximately one-third of asymptomatic close contacts with negative chest radiographic and bacteriological/molecular results for active tuberculosis. Tuberculosis with minimal changes challenge the validity of simply dichotomizing cases of recent M. tuberculosis infections in contacts depending on the presence of X-ray abnormalities as the recent infections may spontaneously regress, remain stagnant, or progress to active tuberculosis in human and nonhuman primate studies. Whether contacts with tuberculosis with minimal changes are interpreted as having active tuberculosis or latent tuberculosis has clinical implications in terms of specific benefits and harms under the current contact management. Advanced imaging tools may help further stratify contacts intensely exposed to M. tuberculosis on a continuous spectrum from latent tuberculosis to incipient, subclinical and active tuberculosis. Identifying incipient tuberculosis would provide an opportunity for earlier and tailored treatment before active tuberculosis is established.

The Association Between Bacille Calmette-Guérin Vaccination and Nontuberculous Mycobacterial Pulmonary Disease

This study aimed to investigate the association between Bacille Calmette-Guérin (BCG) vaccination and nontuberculous mycobacterial pulmonary disease (NTM-PD). Patients in the prospective NTM-PD cohort were matched to healthy controls to measure the association between BCG and NTM-PD development. The clinical course of NTM-PD patients was also evaluated to investigate the association between BCG and NTM-PD progression. BCG scars were not associated with NTM-PD development (adjusted odds ratio [OR], 2.04; 95% confidence interval [CI], 0.96-4.34) or progression (adjusted OR, 1.61; 95% CI, 0.92-2.81). In conclusion, BCG vaccination was not associated with the development or progression of NTM-PD.

Image Correlation-Based Method to Assess Ciliary Beat Frequency in Human Airway Organoids

Ciliary movements within the human airway are essential for maintaining a clean lung environment. Motile cilia have a characteristic ciliary beat frequency (CBF). However, CBF measurement with current video microscopic techniques can be error-prone due to the use of the single-point Fourier transformation, which is often biased for ciliary measurements. Herein, we describe a new video microscopy technique that harnesses a metric of motion-contrast imaging and image correlation for CBF analysis. It can provide objective and selective CBF measurements for individual motile cilia and generate CBF maps for the imaged area. The measurement performance of our methodology was validated with in vitro human airway organoid models that simulated an actual human airway epithelium. The CBF determined for the region of interest (ROI) was equal to that obtained with manual counting. The signal redundancy problem of conventional methods was not observed. Moreover, the obtained CBF measurements were robust to optical focal shifts, and exhibited spatial heterogeneity and temperature dependence. This technique can be used to evaluate ciliary movement in respiratory tracts and determine whether it is non-synchronous or aperiodic in patients. Therefore, our observations suggest that the proposed method can be clinically adapted as a screening tool to diagnose ciliopathies.

Aminoglycosides and Capreomycin in the Treatment of Multidrug-resistant Tuberculosis: Individual Patient Data Meta-analysis of 12 030 Patients From 25 Countries, 2009-2016

BACKGROUND

As new drugs are developed for multidrug-resistant tuberculosis (MDR-TB), the role of currently used drugs must be reevaluated.

METHODS

We combined individual-level data on patients with pulmonary MDR-TB published during 2009-2016 from 25 countries. We compared patients receiving each of the injectable drugs and those receiving no injectable drugs. Analyses were based on patients whose isolates were susceptible to the drug they received. Using random-effects logistic regression with propensity score matching, we estimated the effect of each agent in terms of standardized treatment outcomes.

RESULTS

More patients received kanamycin (n = 4330) and capreomycin (n = 2401) than amikacin (n = 2275) or streptomycin (n = 1554), opposite to their apparent effectiveness. Compared with kanamycin, amikacin was associated with 6 more cures per 100 patients (95% confidence interval [CI], 4-8), while streptomycin was associated with 7 (95% CI, 5-8) more cures and 5 (95% CI, 4-7) fewer deaths per 100 patients. Compared with capreomycin, amikacin was associated with 9 (95% CI, 6-11) more cures and 5 (95% CI, 2-8) fewer deaths per 100 patients, while streptomycin was associated with 10 (95% CI, 8-13) more cures and 10 (95% CI, 7-12) fewer deaths per 100 patients treated. In contrast to amikacin and streptomycin, patients treated with kanamycin or capreomycin did not fare better than patients treated with no injectable drugs.

CONCLUSIONS

When aminoglycosides are used to treat MDR-TB and drug susceptibility test results support their use, streptomycin and amikacin, not kanamycin or capreomycin, are the drugs of choice.

Anxiety and depression in patients with nontuberculous mycobacterial pulmonary disease: a prospective cohort study in South Korea

BACKGROUND

The mental health of patients with nontuberculous mycobacterial pulmonary disease (NTM-PD) has been underestimated.

RESEARCH QUESTION

What is the prevalence of, associated factors for, and clinical impact of anxiety and depression in patients with NTM-PD?

STUDY DESIGN AND METHODS

Among the patients diagnosed with NTM-PD between July 1, 2011 and December 31, 2019, who were a part of Seoul National University Hospital's prospective cohort, we included those who completed the Hospital Anxiety and Depression Scale (HADS) at least twice. Multivariable logistic regression analysis was used to identify the factors associated with anxiety and depression. Multilevel mixed-effects regression was used to analyze the HADS scores' longitudinal trends.

RESULTS

A total of 368 patients were included in this study, including 84 (22.8%) with anxiety (HADS-A score ≥8) and 83 (22.5%) with depression (HADS-D score ≥8). The presence of cough (adjusted odds ratio [aOR] 2.01, 95% confidence interval [CI] 1.19-3.39) and febrile sensation (aOR 4.45, 95% CI 2.13-9.30) were associated with anxiety, whereas dyspnea (aOR 4.13, 95% CI 1.38-12.37) and febrile sensation (aOR 2.91, 95% CI 1.38-6.13) were associated with depression. Although the HADS scores of patients with anxiety or depression at the time of enrollment and throughout the follow-up period were higher than those without, these scores declined significantly within one year after enrollment. Patients with anxiety (P=0.006) or depression (P=0.004) received antibiotic treatment more frequently than those without. Treatment outcomes did not differ depending on the initial anxiety or depression status.

INTERPRETATION

Anxiety and depression were common in patients with NTM-PD and were associated with patient-reported symptoms. While these persisted over time, the treatment outcomes did not differ.

Outcomes of adjunctive surgery for nontuberculous mycobacterial pulmonary disease

Background

Owing to the unsatisfactory results of antibiotic treatment alone, surgical resection is currently considered as adjunctive therapy in patients with nontuberculous mycobacterial pulmonary disease (NTM-PD). However, reports regarding the outcomes of surgery vary considerably by institution. Here, we investigated the surgical outcomes and risk factors associated with unfavorable outcomes after surgery.

Methods

We analyzed patients with NTM-PD who underwent pulmonary resection at Seoul National University Hospital between January 1, 2006, and December 31, 2020, and assessed the types of surgical procedures, complications, and long-term outcomes. Multivariate logistic regression analysis was used to identify the risk factors associated with treatment refractoriness or recurrence after surgery.

Results

Among 67 patients who underwent surgery during the study period, the most common indication for surgery was persistent culture positivity despite rigorous medical treatment (80.6%), followed by longstanding cavitary lesions or radiographic aggravation (10.4%) and massive hemoptysis (4.5%). Among 53 patients with positive mycobacterial cultures at the time of surgery, 38 (71.7%) achieved initial negative culture conversion, 9 (17.0%) of whom experienced recurrence. Nine (13.4%) patients experienced postoperative complications, which were managed without lasting morbidity and mortality. Female sex (adjusted odds ratio [aOR] 6.63; 95% confidence interval [CI] 1.04–42.4; P = .046), preoperative positive mycobacterial culture (aOR 5.87; 95 %CI 1.04–33.08; P = .045), and residual lesions (aOR 6.86; 95 %CI 1.49–31.56; P = .013) were associated with refractoriness or recurrence.

Conclusions

Pulmonary resection is a reasonable treatment modality for patients with refractory NTM-PD or major complications such as massive hemoptysis. The potential risk factors associated with unfavorable outcomes included female sex, preoperative positive mycobacterial culture, and residual lesions after surgery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01679-0.

Determination of Clinical Characteristics of Mycobacterium kansasii-Derived Species by Reanalysis of Isolates Formerly Reported as M. kansasii

Background

Seven genotypic subtypes of Mycobacterium kansasii were recently demonstrated to represent distinct species based on phylogenomic analysis. Mycobacterium kansasii sensu stricto (formerly known as subtype 1) is most frequently associated with human diseases; only a few studies have compared the diverse clinical characteristics of M. kansasii subtypes, including their drug susceptibilities. We determined the actual incidence of infections caused by each subtype of M. kansasii and identified their clinical characteristics.

Methods

We subtyped isolates identified as M. kansasii over the last 10 years at a tertiary care hospital. Percent identity score of stored sequencing data was calculated using curated reference sequences of all M. kansasii subtypes. Clinical characteristics were compared between those classified as subtype 1 and other subtypes. Student's t-test, Wilcoxon rank-sum test, and Fisher's exact test were used for comparisons.

Results

Overall, 21.7% of the isolates were identified as species distinct from M. kansasii. The proportion of patients with subtype 1 M. kansasii infection who received treatment was significantly higher than that of patients with other subtype infections (55.3% vs. 7.7%, P=0.003). Only patients with subtype 1 infection received surgical treatment. Non-subtype 1 M. kansasii isolates showed a higher frequency of resistance to ciprofloxacin and trimethoprim/sulfamethoxazole.

Conclusions

Non-subtype 1 M. kansasii isolates should be separately identified in routine clinical laboratory tests for appropriate treatment selection.

Efficacy of Health Coaching and an Electronic Health Management Program: Randomized Controlled Trial

BACKGROUND

For chronic disease management, self-management strategies are essential to achieve sustained improvement.

OBJECTIVE

Our study evaluated the efficacy of health coaching and a self-management strategy-based electronic program on self-management strategies for patients with osteoporosis, chronic respiratory disease, or arthritis.

DESIGN

Three-arm randomized controlled trial, pilot study PARTICIPANTS: Fifty-four participants INTERVENTIONS: The first intervention group (n = 53) received a self-management strategy-based electronic program and 12 weeks of health coaching (20 sessions). The second intervention group received the information and communications technology (ICT) program; the control group received usual care and an educational booklet about self-management of chronic diseases.

MAIN MEASURES

The primary outcome was the difference in the change of the mean of self-management strategy scores. Secondary outcomes included depression (PHQ-9), physical activity (Godin Leisure Exercise Questionnaire), and health habit maintenance (transtheoretical model) after 12 weeks in the program.

KEY RESULTS

The combination of health coaching and ICT was superior to control group (change 18.5 vs. - 2.6, adjusted difference = 24.5, p < 0.001); however, the ICT alone group was not superior to the control group (change 8.0 vs. - 2.6, adjusted difference = 8.0, p = 0.156). As a result of evaluating the change in the percentage of people with positive stage changes in the transtheoretical model of health habits, regular exercise (p = 0.008), a balanced diet (p = 0.005), helping others (p = 0.001), and living with loved ones (p = 0.038) showed significant differences. There was no significant difference in the changes in percentage of patients with depressive symptoms in comparison with control group; however, there was in comparison with control group among groups (p = 0.033). Compared to the control group, the proportion of patients who achieved an exercise amount of 12.5 MET or higher was significantly higher (p = 0.028) in the health coaching and ICT group.

CONCLUSIONS

The combination of ICT + health coaching led to improvement in self-management as well as in increasing exercise, and several healthy behaviors.

TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT03294057.

Erratum: Correction of Text and Table in the Article "Establishing a Patient-centered Longitudinal Integrated Clerkship: Early Results from a Single Institution"

This corrects the article on p. e419 in vol. 35, PMID: 33372421.

Comparison of QuantiFERON-TB Gold Plus and QuantiFERON-TB Gold In-Tube tests for patients with active and latent tuberculosis: A prospective cohort study

INTRODUCTION

We aimed to determine the diagnostic performance and clinical value of the QuantiFERON-TB Gold In-Tube (QFT-GIT) and QuantiFERON-TB Gold Plus (QFT-Plus) tests in patients with active tuberculosis (TB) or latent TB infection (LTBI).

METHODS

We prospectively enrolled 140 patients, including 63 with active TB and 77 with LTBI, between March 2017 and October 2018. QFT-GIT and QFT-Plus were performed simultaneously in all subjects.

RESULTS

QFT-Plus and QFT-GIT test results showed significant agreement, in both active TB and LTBI patients, in terms of the interferon-γ concentration and interpretation result. QFT-Plus had higher sensitivity than QFT-GIT for predicting active TB (82.5% vs. 77.8%) and showed fewer false-negative and indeterminate results in both active TB and LTBI patients due to its "TB2 tube". The QFT-Plus TB2-TB1 value was higher in the active TB group than in the LTBI group. The QFT-Plus TB1-Nil and TB2-Nil values were useful in predicting remote LTBI, rather than recent LTBI.

CONCLUSIONS

QFT-Plus showed good agreement with QFT-GIT in both active TB and LTBI patients, and higher sensitivity for predicting active TB than QFT-GIT. The QFT-Plus TB2 tube results, which reflect CD8⁺ T cell immunity, may improve predictive accuracy and detection of the immune response associated with active TB and LTBI.

Impact of COVID-19 on Lifestyle, Personal Attitudes, and Mental Health Among Korean Medical Students: Network Analysis of Associated Patterns

The current COVID-19 pandemic have affected our daily lifestyle, pressed us with fear of infection, and thereby changed life satisfaction and mental health. The current study investigated influencing cascade of changes during the COVID-19 among the lifestyle, personal attitudes, and life (dis)satisfaction for medical students, using network-based approaches. This cross-sectional survey used self-reports of 454 medical students during June and July of 2020. Depressive mood, anxiety, and intention to drop out of school were observed in 11.9, 18.5, and 38.3% of medical students, respectively. Directed acyclic graph that estimated directional propagation of the COVID-19 in medical students' daily lives initiated from the perception of unexpected event, propagated to nervous and stressed feeling, trouble relaxing, feeling like a failure, and were followed by trouble concentrating, feeling loss of control for situation, and fear of infecting colleagues. These six features were also principal mediators within the intra-individual covariance networks comprised of changed lifestyle, personal attitude, and mental health at COVID-19 pandemic. Psychosocial supports targeting nervousness, trouble relaxing and concentrating, fear of spreading infection to colleagues, feelings of a failure or loss of situational control are required for better mental health of medical students during the COVID-19 pandemic.

Deep Learning to Determine the Activity of Pulmonary Tuberculosis on Chest Radiographs

Background Determining the activity of pulmonary tuberculosis on chest radiographs is difficult. Purpose To develop a deep learning model to identify active pulmonary tuberculosis on chest radiographs. Materials and Methods Chest radiographs were retrospectively gathered from a multicenter consecutive cohort with pulmonary tuberculosis who were successfully treated between 2011 and 2017, along with normal radiographs to enrich a negative class. The pretreatment and posttreatment radiographs were labeled as positive and negative classes, respectively. A neural network was trained with those radiographs to calculate the probability of active versus healed tuberculosis. A single-center consecutive cohort (test set 1; 89 patients, 148 radiographs) and data from one multicenter randomized controlled trial (test set 2; 366 patients, 3774 radiographs) were used to test the model. The area under the receiver operating characteristic curve (AUC) was used to evaluate the performance of the model and of the four expert readers. Results In total, 6654 pre- and posttreatment radiographs from 3327 patients (mean age ± standard deviation, 55 years ± 19; 1884 men) with pulmonary tuberculosis and 3182 normal radiographs from as many patients (mean age, 53 years ± 14; 1629 men) were gathered. For test set 1, the model showed a higher AUC (0.83; 95% CI: 0.73, 0.89) than one pulmonologist (0.69; 95% CI: 0.61, 0.76; P < .001) and performed similarly to the other readers (AUC, 0.79-0.80; P = .14-.23). For 200 randomly selected radiographs from test set 2, the model had a higher AUC (0.84) than the pulmonologists (0.71 and 0.74; P < .001 and .01, respectively) and performed similarly to the radiologists (0.79 and 0.80; P = .08 and .06, respectively). The model output increased by 0.30 on average with a higher degree of smear positivity (95% CI: 0.20, 0.39; P < .001) and decreased during treatment (baseline, 3 months, and 6 months: 0.85, 0.51, and 0.26, respectively). Conclusion A deep learning model performed similarly to radiologists for accurately determining the activity of pulmonary tuberculosis on chest radiographs; it also was able to follow posttreatment changes. © RSNA, 2021 Online supplemental material is available for this article.

Management of Drug Toxicity in Mycobacterium avium Complex Pulmonary Disease: An Expert Panel Survey

Adverse events are frequent in nontuberculous mycobacteria pulmonary disease treatment, but evidence to support their management is scarce. An expert panel survey on management of adverse events shows consistent opinions on management of hepatoxicity, ocular toxicity, ototoxicity, tinnitus, and gastrointestinal upset. These opinions can provide assistance in individual patient management decisions.

Impact of Susceptibility to Injectable Antibiotics on the Treatment Outcomes of Mycobacterium abscessus Pulmonary Disease

Background

Current guidelines recommend a susceptibility-based regimen for Mycobacterium abscessus subspecies abscessus pulmonary disease (MAB-PD), but the evidence is weak. We aimed to investigate the association between treatment outcomes and in vitro drug susceptibility to injectable antibiotics in MAB-PD patients.

Methods

We enrolled MAB-PD patients treated with intravenous amikacin and beta-lactams for ≥4 weeks at 4 referral hospitals in Seoul, South Korea. Culture conversion and microbiological cure at 1 year were evaluated based on susceptibility to injectable antibiotics among patients treated with those antibiotics for ≥2 weeks.

Results

A total of 82 patients were analyzed. The mean age was 58.7 years, and 65.9% were women. Sputum culture conversion and microbiological cure were achieved in 52.4% and 41.5% of patients, respectively. Amikacin was the most common agent to which the M. abscessus subspecies abscessus isolates were susceptible (81.7%); 9.8% and 24.0% of the isolates were resistant to cefoxitin and imipenem, respectively. The clarithromycin-inducible resistance (IR) group (n = 65) had a lower microbiological cure rate than the clarithromycin-susceptible group (35.4% vs 64.7%). The treatment outcomes appeared to be similar regardless of in vitro susceptibility results with regard to intravenous amikacin, cefoxitin, imipenem, and moxifloxacin. In the subgroup analysis of the clarithromycin-IR group, the treatment outcomes did not differ according to antibiotic susceptibility.

Conclusions

We did not find evidence supporting the use of susceptibility-based treatment with intravenous amikacin and beta-lactams in patients with MAB-PD. Further research is required.

A systematic review and meta-analysis of regional risk factors for critical outcomes of COVID-19 during early phase of the pandemic

The mortality rates of COVID-19 vary across the globe. While some risk factors for poor prognosis of the disease are known, regional differences are suspected. We reviewed the risk factors for critical outcomes of COVID-19 according to the location of the infected patients, from various literature databases from January 1 through June 8, 2020. Candidate variables to predict the outcome included patient demographics, underlying medical conditions, symptoms, and laboratory findings. The risk factors in the overall population included sex, age, and all inspected underlying medical conditions. Symptoms of dyspnea, anorexia, dizziness, fatigue, and certain laboratory findings were also indicators of the critical outcome. Underlying respiratory disease was associated higher risk of the critical outcome in studies from Asia and Europe, but not North America. Underlying hepatic disease was associated with a higher risk of the critical outcome from Europe, but not from Asia and North America. Symptoms of vomiting, anorexia, dizziness, and fatigue were significantly associated with the critical outcome in studies from Asia, but not from Europe and North America. Hemoglobin and platelet count affected patients differently in Asia compared to those in Europe and North America. Such regional discrepancies should be considered when treating patients with COVID-19.

Reintroduction of Antituberculous Drugs in Patients with Antituberculous Drug-Related Drug Reaction with Eosinophilia and Systemic Symptoms

BACKGROUND

Patients who suffered drug reaction with eosinophilia and systemic symptom (DRESS) during the treatment of tuberculosis (TB) commonly experience multidrug hypersensitivity reactions resulting in limited anti-TB drug choices. Therefore, reintroduction based on a desensitization protocol may be an option to resume anti-TB medication.

OBJECTIVE

To evaluate the outcomes and safety of resuming anti-TB drugs according to reintroduction methods in patients with anti-TB drug-related DRESS.

METHODS

A retrospective cohort of patients who had experienced anti-TB drug-related severe cutaneous adverse reactions from 2011 to 2017 was established from separate 5 institutions.

RESULTS

Anti-TB medication was resumed in 27 of 29 patients with anti-TB drug-related DRESS through complete changing regimen (n = 9), reintroduction by a graded challenge (n = 5), or reintroduction using a desensitization protocol (n = 13). Nine patients completely changed their anti-TB regimen to second-line TB drugs, but only 1 (11.1%) succeeded in maintaining new anti-TB drugs. The other 8 failed to take drugs due to the occurrence of hypersensitivity reactions to the newly introduced anti-TB drugs. Two (40.0%) of 5 patients who underwent graded rechallenges successfully completed anti-TB drugs, whereas 3 (60%) failed to resume anti-TB drugs due to the recurrence of hypersensitivity reactions. In 13 patients who resumed anti-TB drugs using a desensitization protocol, no one who underwent desensitization developed recurrence of DRESS; 11 (84.6%) eventually completed anti-TB treatment and 2 eventually failed to complete anti-TB treatment due to late-onset itching and drug-induced liver injury.

CONCLUSIONS

Resuming anti-TB medication based on desensitization protocols may be a safe and effective option for those with anti-TB drug-related DRESS.

Outcomes of multidrug-resistant tuberculosis treated with bedaquiline or delamanid

BACKGROUND

Since September 1, 2016, bedaquiline and delamanid have been administered for treatment of patients with multidrug-resistant/rifampicin-resistant tuberculosis after the official approval in South Korea. This study aimed to assess and compare the final treatment outcomes of patients who received bedaquiline with those of patients who received delamanid.

METHODS

This is a nationwide cohort study of patients with multidrug-resistant/rifampicin-resistant tuberculosis in whom bedaquiline or delamanid was administered from September 1, 2016, to February 28, 2018, after receiving the official approval in South Korea. Patients were classified into the bedaquiline and delamanid group according to the first used drug. We evaluated and compared the final treatment outcomes between the groups.

RESULTS

During the study period, 284 patients with multidrug-resistant/rifampicin-resistant tuberculosis were approved to use bedaquiline or delamanid and 260 were included in the final analysis; 119 (45.8%) and 141 patients (54.2%) were classified into bedaquiline and delamanid groups, respectively. Among them, 30 patients (11.5%) exhibited additional resistance to second-line injectable drugs, 94 patients (36.2%) had additional resistance to fluoroquinolones, and 37 patients (14.2%) had resistance to both drugs. The overall treatment success rate was 79.2%. Initiation of bedaquiline rather than delamanid was not associated with treatment success (adjusted odds ratio = 0.671, 95% confidence interval = 0.350-1.285). Frequencies of adverse events were not significantly different between the two groups.

CONCLUSIONS

Initial choice of bedaquiline or delamanid did not make any significant difference in the final treatment outcome or the frequencies of adverse events among patients with multidrug-resistant/rifampicin-resistant tuberculosis.

Clinical Implications of Size of Cavities in Patients With Nontuberculous Mycobacterial Pulmonary Disease: A Single-Center Cohort Study

Background

The presence of cavities is associated with unfavorable prognosis in patients with nontuberculous mycobacterial pulmonary disease (NTM-PD). However, little is known about the characteristics of such cavities and their impact on clinical outcomes. The aim of this study was to investigate the size of cavities and their implications on treatment outcomes and mortality in patients with NTM-PD.

Methods

We included patients diagnosed with NTM-PD at Seoul National University Hospital between January 1, 2007, and December 31, 2018. We measured the size of cavities on chest computed tomography scans performed at the time of diagnosis and used multivariable logistic regression and Cox proportional hazards regression analysis to investigate the impact of these measurements on treatment outcomes and mortality.

Results

The study cohort comprised 421 patients (noncavitary, n = 329; cavitary, n = 92) with NTM-PD. During a median follow-up period of 49 months, 118 (35.9%) of the 329 patients with noncavitary and 64 (69.6%) of the 92 patients with cavitary NTM-PD received antibiotic treatment. Cavities >2 cm were associated with worse treatment outcomes (adjusted odds ratio, 0.41; 95% CI, 0.17–0.96) and higher mortality (adjusted hazard ratio, 2.52; 95% CI, 1.09–5.84), while there was no difference in treatment outcomes or mortality between patients with cavities ≤2 cm and patients with noncavitary NTM-PD.

Conclusions

Clinical outcomes are different according to the size of cavities in patients with cavitary NTM-PD; thus, the measurement of the size of cavities could help in making clinical decisions.

BACES Score for Predicting Mortality in Nontuberculous Mycobacterial Pulmonary Disease

Rationale: Because the prognosis of nontuberculous mycobacterial pulmonary disease varies, a scoring system predicting mortality is needed.Objectives: We aimed to develop a novel scoring system to predict mortality among patients with nontuberculous mycobacterial pulmonary disease.Methods: We included patients age ≥20 years with newly diagnosed nontuberculous mycobacterial pulmonary disease, with Mycobacterium avium, M. intracellulare, M. abscessus subsp. abscessus, or M. abscessus subsp. massiliense. Cox proportional hazards models were used to identify predictors of mortality in a derivation cohort, and a scoring system was developed. It was validated in an independent prospective cohort.Measurements and Main Results: A total 1,181 and 377 patients were included in the derivation and validation cohorts, respectively. In the final model, body mass index <18.5 kg/m² (1 point), age ≥65 years (1 point), presence of cavity (1 point), elevated erythrocyte sedimentation rate (1 point), and male sex (1 point) were selected as predictors for mortality. We named this novel scoring system BACES (body mass index, age, cavity, erythrocyte sedimentation rate, and sex). Harrell's C-index for the BACES score was 0.812 (95% confidence interval, 0.786-0.837) in the derivation cohort and 0.854 (95% confidence interval, 0.797-0.911) in the validation cohort, indicating excellent discrimination performance. The estimated 5-year risk of mortality was 1.2% with BACES score 0 and 82.9% with BACES score 5.Conclusions: We developed the BACES score, which could accurately predict mortality among patients with nontuberculous mycobacterial pulmonary disease caused by M. avium, M. intracellulare, M. abscessus subsp. abscessus, or M. abscessus subsp. massiliense.

Impact of body mass index on development of nontuberculous mycobacterial pulmonary disease

The incidence and prevalence of nontuberculous mycobacterial pulmonary disease (NTM-PD) have been increasing worldwide. The risk of NTM-PD may be higher in undernourished populations. In this study, we tried to elucidate the impact of body mass index (BMI) and its change on development of NTM-PD.We performed a retrospective cohort study including South Koreans aged >40 years who underwent biennial National Health Insurance System (NHIS) health check-ups in both 2005 and 2009 or 2006 and 2010. We monitored eligible individuals from the study initiation date (NHIS health check-up date in 2009 or 2010) until the diagnosis of NTM-PD or until December 31, 2017. Enroled individuals were classified based on BMI at initiation date. By calculating hazard ratios, we compared NTM-PD incidence per 100 000 person-years by BMI group and by BMI change.A total of 5 670 229 individuals were included in the final analysis. Compared with the BMI <18.5 kg·m^-2 group, the incidence of NTM-PD gradually decreased with increased BMI (adjusted hazard ratio 0.38, 95% confidence interval (CI) 0.35-0.42 for BMI 18.5-22.9; 0.17, 95% CI 0.15-0.19 for BMI 23-24.9; 0.1, 95% CI 0.09-0.11 for BMI 25-29.9; and 0.1, 95% CI 0.07-0.13 for BMI ≥30). A BMI decrease of ≥1 kg·m^-2 over 4 years increased the incidence of NTM-PD (adjusted hazard ratio 1.08, 95% CI 1.01-1.16) whereas a BMI increase of ≥1 kg·m^-2 decreased the incidence of NTM-PD (adjusted hazard ratio 0.77, 95% CI 0.71-0.83).In conclusion, BMI was inversely related to development of NTM-PD and weight loss increased the risk of NTM-PD.

How medical education survives and evolves during COVID-19: Our experience and future direction

Background

Due to the outbreak of coronavirus disease 2019 (COVID-19), school openings were postponed worldwide as a way to stop its spread. Most classes are moving online, and this includes medical school classes. The authors present their experience of running such online classes with offline clinical clerkship under pandemic conditions, and also present data on student satisfaction, academic performance, and preference.

Methods

The medical school changed every first-year to fourth-year course to an online format except the clinical clerkship, clinical skills training, and basic laboratory classes such as anatomy lab sessions. Online courses were pre-recorded video lectures or live-streamed using video communication software. At the end of each course, students and professors were asked to report their satisfaction with the online course and comment on it. The authors also compared students’ academic performance before and after the introduction of online courses.

Results

A total of 69.7% (318/456) of students and 35.2% (44/125) of professors answered the questionnaire. Students were generally satisfied with the online course and 62.2% of them preferred the online course to the offline course. The majority (84.3%) of the students wanted to maintain the online course after the end of COVID-19. In contrast, just 13.6% of professors preferred online lectures and half (52.3%) wanted to go back to the offline course. With the introduction of online classes, students' academic achievement did not change significantly in four subjects, but decreased in two subjects.

Conclusions

The inevitable transformation of medical education caused by COVID-19 is still ongoing. As the safety of students and the training of competent physicians are the responsibilities of medical schools, further research into how future physicians will be educated is needed.