Nontuberculous Mycobacteria.

Nontuberculous mycobacteria (NTM) are ubiquitous in the environment and 193 species of NTM have been discovered thus far. NTM species vary in virulence from benign environmental organisms to difficult-to-treat human pathogens. Pulmonary infections remain the most common manifestation of NTM disease in humans and bronchiectasis continues to be a major risk factor for NTM pulmonary disease (NTM PD). This article will provide a useful introduction and framework for clinicians involved in the management of bronchiectasis and NTM. It includes an overview of the epidemiology, pathogenesis, diagnosis, and management of NTM PD. We will address the challenges faced in the diagnosis of NTM PD and the importance of subspeciation in guiding treatment and follow-up, especially in Mycobacterium abscessus infections. The treatment of both Mycobacterium avium complex and M. abscessus, the two most common NTM species known to cause disease, will be discussed in detail. Elements of the recent ATS/ERS/ESCMID/IDSA NTM guidelines published in 2020 will also be reviewed.

Long-term outcomes of tracheobronchial stenosis due to tuberculosis (TSTB) in symptomatic patients: airway intervention vs. conservative management.

BACKGROUND: Patients with tracheobronchial stenosis due to tuberculosis (TSTB) have a variable clinical course and response to treatment including airway intervention. There are no clear guidelines on the best approach to manage such patients. This study examines long-term outcomes of patients with TSTB and factors associated with recurrent symptoms or need for repeat airway intervention following initial bronchoscopic intervention. METHODS: This is a retrospective analysis of patients with TSTB over an 18-year period. Symptoms, radiological, bronchoscopic findings, airway interventions and complications were obtained. Multivariate logistic regression analysis was performed to identify factors predictive of recurrence of symptoms or need for repeat airway intervention. RESULTS: A total of 131 patients with mean age 50±18 years and median follow-up 5 (interquartile range, 2-10) years were included. Nineteen (29.7%) patients underwent balloon dilatation alone, 22 (34.4%) had additional resection or stenting, and 19 (29.7%) underwent all 3 procedures. Among patients conservatively managed, a larger proportion (55.6%) of patients with no recurrence of symptoms had active TB. Patients who developed recurrent symptoms had longer symptom duration (12 vs. 3 months, P=0.025), and more had recurrent lower respiratory tract infections (50% vs. 5.6%, P=0.003), lung collapse (90.0% vs. 41.7%, P=0.011) or linear fibrosis (70.0% vs. 30.6%, P=0.033) compared to those without recurrent symptoms. Bronchomalacia (OR =17.18; 95% CI, 3.43-86.18) and prior bronchoscopic airway resection (OR =4.97; 95% CI, 1.20-20.60) were strongly associated with the recurrence of symptoms or need for repeat airway intervention on multivariate logistic regression analysis. CONCLUSIONS: Bronchomalacia and prior bronchoscopic airway resection are associated with the recurrence of symptoms despite airway intervention. Patients who are diagnosed with TSTB early in the course of active TB may be conservatively managed.

Asthmatic adult with marked blood eosinophilia: is it truly asthma?

A middle-aged woman presented with symptoms suggestive of allergic asthma but with markedly elevated peripheral eosinophilia. She did not respond to inhaled corticosteroids, thereby prompting further investigations. Chest radiograph was normal. CT of the chest revealed bi-apical ground glass opacities. Bronchoalveolar lavage revealed predominantly eosinophilic yield. Autoimmune screen was negative. Bone marrow biopsy showed a normocellular marrow with increased eosinophils. A diagnosis of chronic eosinophilic pneumonia (CEP) was made after exclusion of other causes of eosinophilia. Treatment of her CEP with systemic corticosteroids (prednisolone 0.5 mg/kg/day) resulted in dramatic improvement in symptoms and peripheral eosinophilia.

Impact of simulation training on performance and outcomes of endobronchial ultrasound-guided transbronchial needle aspiration performed by trainees in a tertiary academic hospital.

BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has a high diagnostic yield and low complication rate. Whilst it has been included in international guidelines for the diagnosis and staging of lung cancer, current results are mostly based on EBUS experts performing EBUS-TBNA in centres of excellence. The impact of simulation training on diagnostic yield, complications, scope damage and repair cost in a real-world teaching hospital is unclear. METHODS: A review of our hospital EBUS-TBNA registry from August 2008 to December 2016 was performed. A positive diagnosis was defined as a confirmed histological or microbiological diagnosis based on EBUS sampling. Complications were classified as major or minor according to the British Thoracic Society guidelines. In addition, we assessed the cost of repairs for scope damage before and after simulation training was implemented. Using CUSUM analysis, the learning curves of individual trainees and the institution were plotted. RESULTS: There were 608 EBUS-TBNA procedures included in the study. The number of procedures performed by trainees who underwent conventional training was 331 and those who underwent simulation training performed 277 procedures. Diagnostic yield for trainees without simulation training was 88.2% vs. 84.5% for trainees with simulation training (P=0.179). There was no statistical difference in the diagnostic yield between the groups of trainees (OR: 0.781, 95% CI: 0.418-1.460, P=0.438) after adjusting for risk factors. There was an increase in overall complications from 13.6% to 16.6% (OR: 2.247, 95% CI: 1.297-3.891, P=0.004) after introduction of the simulation training, but a trend to decrease in major complications 3.6% to 0.7% (P=0.112). The cost for scope repairs for the trainees without simulation training was SGD 413.88 per procedure vs. SGD 182.79 per procedure for the trainees with simulation training, with the mean difference being SGD 231.09 per procedure (95% CI: 178.40-640.60, P=0.268). CUSUM analysis showed an increasing learning curve for the trainees with simulation training after an initial competency period. CONCLUSIONS: There was no statistical difference in diagnostic yield from EBUS-TBNA and cost of scope damage after simulation training was introduced into our training program. Interestingly, there was an increase in minor complications. CUSUM analysis can provide additional information on institutional learning curves. The value of simulation training in EBUS-TBNA remains uncertain.