Evidence of mycobacterial disease in COPD patients with lung volume reduction surgery; the importance of histological assessment of specimens: a cohort study.

BACKGROUND: Patients with COPD are at risk of non-tuberculous mycobacterial infection (NTM). This study examined the histology of lung tissue from COPD patients following lung volume reduction with particular focus on evidence of mycobacterial infection. METHODS: Retrospective histological study of 142 consecutive lung volume reduction surgical specimens (126 separate patients) at Royal Brompton Hospital between 2000 - 2013, with prospectively collected preoperative data on exacerbation rate, lung function and body mass index. RESULTS: 92% of patients had at least one other histological diagnosis in addition to emphysema. 10% of specimens had histological evidence of mycobacterial infection, one with co-existent aspergilloma. Mycobacteria were only identified in those patients with granulomas that were necrotising. These patients had higher exacerbation rates, lower TLCO and FEV1. CONCLUSION: A proportion of severe COPD patients will have evidence of mycobacterial infection despite lack of clinical and radiological suspicion. This may have implications for long-term management of these patients.

COPD causation and workplace exposures: an assessment of agreement among expert clinical raters.

BACKGROUND: Although occupational exposure is a known risk factor for Chronic Obstructive Pulmonary Disease (COPD), it is difficult to identify specific occupational contributors to COPD at the individual level to guide COPD prevention or for compensation. The aim of this study was to gain an understanding of how different expert clinicians attribute likely causation in COPD. METHODS: Ten COPD experts and nine occupational lung disease experts assigned occupational contribution ratings to fifteen hypothetical cases of COPD with varying combinations of occupational and smoking exposures. Participants rated the cause of COPD as the percentage contribution to the overall attribution of disease for smoking, occupational exposures and other causes. RESULTS: Increasing pack-years of tobacco smoking was associated with significantly decreased proportional occupational causation ratings. Increasing weighted occupational exposure was associated with increased occupational causation ratings by 0.28% per unit change. Expert background also contributed significantly to the proportion of occupational causation rated, with COPD experts rating on average a 9.4% greater proportion of occupational causation per case. CONCLUSION: Our findings support the notion that respiratory physicians are able to assign attribution to different sources of causation in COPD, taking into account both smoking and occupational histories. The recommendations on whether to continue to work in the same job also differ, the COPD experts being more likely to recommend change of work rather than change of work practice.

Ambulatory oxygen in fibrotic lung disease (AmbOx): study protocol for a randomised controlled trial.

BACKGROUND: Fibrotic interstitial lung diseases (ILDs) are chronic and often progressive conditions resulting in substantial morbidity and mortality. Shortness of breath, a symptom often linked to oxygen desaturation on exertion, is tightly linked to worsening quality of life in these patients. Although ambulatory oxygen is used empirically in their treatment, there are no ILD-specific guidelines on its use. To our knowledge, no studies are available on the effects of ambulatory oxygen on day-to-day life in patients with ILD. METHODS/DESIGN: Ambulatory oxygen in fibrotic lung disease (AmbOx) is a multicentre, randomised controlled crossover trial (RCT) funded by the Research for Patient Benefit Programme of the National Institute for Health Research. The trial will compare ambulatory oxygen used during daily activities with no ambulatory oxygen in patients with fibrotic lung disease whose oxygen saturation (SaO2) is ≥94% at rest, but drops to ≤88% on a 6-min Walk Test. The randomised controlled trial (RCT) will evaluate the effects on health status (measured by the King's Brief ILD Questionnaire: K-BILD) of ambulatory oxygen used at home, at an optimal flow rate determined by titration at screening visit, and administered for a 2-week period, compared to 2 weeks off oxygen. Key secondary outcomes will include breathlessness on activity scores, as measured by the University of California San Diego Shortness of Breath Questionnaire, global patient assessment of change scores, as well as quality of life scores (St George's Respiratory Questionnaire), anxiety and depression scores (Hospital Anxiety and Depression Scale), activity markers measured by SenseWear Armbands, pulse oximetry measurements, patient-reported daily activities, patient- and oxygen company-reported oxygen cylinder use. The study also includes a qualitative component and will explore in interviews patients' experiences of the use of a portable oxygen supply and trial participation in a subgroup of 20 patients and carers. DISCUSSION: This is the first RCT of the effects of ambulatory oxygen during daily life on health status and breathlessness in fibrotic lung disease. The results generated should provide the basis for setting up ILD-specific guidelines for the use of ambulatory oxygen. TRIAL REGISTRATION: National Clinical Trials Registry, identifier: NCT02286063 . Registered on 8 October 2014 (retrospectively registered).