Respiratory and lower limb muscle function in interstitial lung disease.

Growing evidence suggests that respiratory and limb muscle function may be impaired in patients with interstitial lung disease (ILD). Importantly, muscle dysfunction could promote dyspnoea, fatigue and functional limitation all of which are cardinal features of ILD. This article examines the risk factors for skeletal muscle dysfunction in ILD, reviews the current evidence on overall respiratory and limb muscle function and focuses on the occurrence and implications of skeletal muscle dysfunction in ILD. Research limitations and pathways to address the current knowledge gaps are highlighted.

Immune response to mycobacterial infection: lessons from flow cytometry.

Detecting and treating active and latent tuberculosis are pivotal elements for effective infection control; yet, due to their significant inherent limitations, the diagnostic means for these two stages of tuberculosis (TB) to date remain suboptimal. This paper reviews the current diagnostic tools for mycobacterial infection and focuses on the application of flow cytometry as a promising method for rapid and reliable diagnosis of mycobacterial infection as well as discrimination between active and latent TB: it summarizes diagnostic biomarkers distinguishing the two states of infection and also features of the distinct immune response against Mycobacterium tuberculosis (Mtb) at certain stages of infection as revealed by flow cytometry to date.

Daily Physical Activity in Asthma and the Effect of Mepolizumab Therapy.

For the various asthma-specific beneficial effects of physical activity, daily physical activity (DPA) and the potential of asthma therapies on DPA require better characterization. Hence, we aimed to determine (a) the DPA of asthma patients, and (b) the effect of add-on mepolizumab on the DPA of severe asthma patients. Methods: Adult outpatients with mild-to-moderate or severe asthma had accelerometer assessment of DPA. Severe asthma patients who were commenced on mepolizumab had their DPA reassessed after 12 months. Results: For the total cohort (n = 36), daily step count, time in moderate-to-vigorous physical activity (MVPA), MVPA volume and Movement Intensity (MI) were 7806 ± 3823 steps, 123 (interquartile range, 63) min, 657 ± 255 MET·min and 1.96 (0.45) m/s2, respectively. All patients met at least one recommendation for DPA but less than half met recommendations for vigorous DPA. Patients on mepolizumab therapy increased daily step count (646 steps; 9%), time in MVPA (20 min; 21%), MVPA volume (87 MET·min; 17%) and MI (0.11 m/s2; 6%) for the same amount of moving time; lung function, asthma control and health-related quality of life also improved. Conclusions: Analysis of the first national data on DPA in asthma and novel comparison against current applicable guidelines and identified beneficial thresholds showed borderline levels of DPA with room for improvement especially for severe asthma patients. In a non-sedentary cohort of severe asthma patients, mepolizumab conferred significant and meaningful improvements in DPA.

Physical Activity: A Missing Link in Asthma Care.

Asthma is the commonest respiratory disease and one of unceasingly increasing prevalence and burden. As such, asthma has attracted a major share or scientific interest and clinical attention. With the various clinical and pathophysiological aspects of asthma having been extensively investigated, the important association between asthma and physical activity remains underappreciated and insufficiently explored. Asthma impacts adversely on physical activity. Likewise, poor physical activity may lead to worse asthma outcomes. This concise clinical review presents the current recommendations for physical activity, discusses the available evidence on physical activity in asthma, and examines the causes of low physical activity in adult asthmatic patients. It also reviews the effect of daily physical activity and exercise training on the pathology and clinical outcomes of asthma. Finally, it summarizes the evidence on interventions targeting physical activity in asthma.

25-hydroxyvitamin D in malignant pleural disease: a prospective cohort study.

INTRODUCTION: Growing evidence suggests a role of vitamin D in various cancers but the significance of vitamin D in malignant pleural disease remains unexplored. We sought to investigate the concentration and diagnostic role of 25-hydroxyvitamin D (25(OH)D) in malignant pleural effusions. MATERIALS AND METHODS: Prospective study of consecutive treatment-naïve patients with a new diagnosis of pleural effusion. RESULTS: Seventy-eight patients were studied, 45 of whom had malignant pleural effusions. Concentration of 25(OH)D in pleural fluid was significantly higher than serum in both malignant (15.2 ng/mL (9.7, 25.6) versus 10.2 ng/mL (6.4, 17.7), P < .001) and benign (11.4 ng/mL (8.4, 23.6) versus 7.9 (5.9, 16.1), P < .001) pleural disease. Pleural fluid 25(OH)D was almost significantly higher in exudates compared to transudates (P = .050) but it did not differ significantly between malignant and benign effusions (P = .217) and it was not diagnostic for malignant pleural disease (area under the ROC curve .58, 95% CI .45-.71). CONCLUSIONS: In subjects with unselected pleural effusions, 25(OH)D in pleural fluid was not diagnostic for malignant pleural disease. The novel finding of convincingly and consistently higher 25(OH)D in pleural fluid than serum suggests a role for vitamin D in pleural disease and merits further research.

Validation of impedance cardiography in pulmonary arterial hypertension.

BACKGROUND: Non-invasive methods of measuring cardiac output are highly desirable in pulmonary arterial hypertension (PAH). We therefore sought to validate impedance cardiography (ICG) against thermodilution (TD) and cardiac magnetic resonance (CMR) in the measurement of cardiac output in patients under investigation for PAH. METHODS: A prospective, cross-sectional study was performed to compare single-point measurements of cardiac output obtained by impedance cardiography (COICG ) technology (PhysioFlow® ) with (i) contemporaneous TD measurements (COTD ) at rest and steady-state exercise during right heart catheterization and (ii) CMR measurements (COCMR ) at rest obtained within 72 h. RESULTS: Paired COICG and COTD measurements were obtained in 25 subjects at rest and 16 subjects at exercise. COCMR measurements were obtained in 16 subjects at rest. There was unsatisfactory correlation and agreement between COICG and COTD at rest (r = 0·42, P = 0·035; bias: 1·21 l min-1 , 95% CI: -2·33 to 4·75 l min-1 ) and exercise (r = .65, P = .007; bias: 1·41 l min-1 ; 95% CI: -3·99 to 6·81 l min-1 ) and in the change in COICG and COTD from rest to exercise (r = 0·53, P = 0·033; bias: 0·76 l min-1 , 95% CI: -3·74 to 5·26 l min-1 ). There was also a lack of correlation and unsatisfactory agreement between resting COICG and COCMR (r = 0·38, P = 0·1; bias: 1·40 l min-1 , 95% CI: -2·48 to 5·28 l min-1 ). In contrast, there was close correlation and agreement between resting COTD and COCMR (r = 0·87, P<0·001; bias: -0·16 l min-1 , 95% CI: -1·97 to 1·65). CONCLUSIONS: In a representative population of patients under investigation for PAH, ICG showed insufficient qualitative and quantitative value in the measurement of resting and exercise cardiac output when compared with TD and CMR.

Pulmonary vascular and cardiac impairment in interstitial lung disease.

Pulmonary vascular and cardiac impairment is increasingly appreciated as a major adverse factor in the natural history of interstitial lung disease. This clinically orientated review focuses on the current concepts in the pathogenesis, pathophysiology and implications of the detrimental sequence of increased pulmonary vascular resistance, pre-capillary pulmonary hypertension and right heart failure in interstitial lung disease, and provides guidance on its management.

A study of clinical and physiological relations of daily physical activity in precapillary pulmonary hypertension.

Daily physical activity is reduced in precapillary pulmonary hypertension (PH), but the underlying mechanisms are inadequately explored. We sought to investigate clinical and physiological relations of daily physical activity and profile differences between less and more active patients with precapillary PH. A prospective, cross-sectional study of 20 patients with precapillary PH who undertook 1) a comprehensive clinical assessment, 2) a preliminary treadmill test, 3) 7-day monitoring of daily walking intensity with triaxial accelerometry, and 4) a personalized treadmill test corresponding to the individual patient mean daily walking intensity with real-time physiological measurements. Significant clinical correlations with individual patient mean walking intensity [1.71 ± 0.27 (SD) m/s2] were observed for log-transformed N-terminal probrain natriuretic peptide (log NT-proBNP; r = -0.75, P = <.001), age (r = -0.70, P = 0.001), transfer factor for carbon monoxide %predicted (r = 0.51, P = 0.022), and 6-min walk distance (r = 0.50, P = 0.026). Significant physiological correlations were obtained for heart rate reserve (r = 0.68, P = 0.001), quadriceps tissue oxygenation index (Q-[Formula: see text]; r = 0.58, P = 0.008), change in Q-[Formula: see text] from rest (r = 0.60, P = 0.006), and ventilatory equivalent for oxygen uptake (r = -0.56, P = 0.013). Stepwise multiple regression analyses retained log NT-proBNP (R2 = 0.55), heart rate reserve (R2 = 0.44), and Q-[Formula: see text] (R2 = 0.13) accounting for a significant variance in individual walking intensity. Less active patients had greater physical activity-induced cardiopulmonary impairment, worse quadriceps oxygenation profile, and compromised health-related quality of life compared with more active patients. These preliminary findings suggest a significant relation between right ventricular and peripheral muscle oxygenation status and reduced daily physical activity in precapillary PH. Further research is warranted to unravel the physiological determinants, establish clinical predictors, and identify beneficial interventions.NEW & NOTEWORTHY Daily physical activity holds promise to be a meaningful, patient-related outcome measure in pulmonary hypertension. In this study, novel findings in a representative sample of patients with precapillary pulmonary hypertension link reduced daily walking activity, as measured by triaxial accelerometry, with compromised right ventricular and pulmonary vascular status, peripheral muscle oxygenation, and health-related quality of life, providing a preliminary insight into the physiological mechanisms and clinical predictors of daily physical activity in precapillary pulmonary hypertension.

Respiratory and limb muscle dysfunction in pulmonary arterial hypertension: a role for exercise training?

Respiratory and limb muscle dysfunction is emerging as an important pathophysiological abnormality in pulmonary arterial hypertension (PAH). Muscle abnormalities appear to occur frequently and promote dyspnea, fatigue, and exercise limitation in patients with PAH. Preliminary data suggest that targeted muscle training may be of benefit, although further evidence is required to consolidate these findings into specific recommendations for exercise training in patients with PAH. This article reviews the current evidence on prevalence, risk factors, and implications of respiratory and limb muscle dysfunction in patients with PAH. It also reviews the impact of exercise rehabilitation on morphologic, metabolic, and functional muscle profile and outcomes in PAH. Future research priorities are highlighted.

The epidemiology of pulmonary nontuberculous mycobacteria: data from a general hospital in Athens, Greece, 2007-2013.

BACKGROUND: The epidemiology of pulmonary nontuberculous mycobacteria (NTM) in Greece is largely unknown. OBJECTIVES: To determine the incidence and the demographic, microbiological, and clinical characteristics of patients with pulmonary NTM infection and pulmonary NTM disease. METHODS: A retrospective review of the demographic, microbiological, and clinical characteristics of patients with NTM culture-positive respiratory specimens from January 2007 to May 2013. RESULTS: A total of 120 patients were identified with at least one respiratory NTM isolate and 56 patients (46%) fulfilled the microbiological ATS/IDSA criteria for NTM disease. Of patients with adequate data, 16% fulfilled the complete ATS/IDSA criteria for NTM disease. The incidence of pulmonary NTM infection and disease was 18.9 and 8.8 per 100.000 inpatients and outpatients, respectively. The spectrum of NTM species was high (13 species) and predominated by M. avium-intracellulare complex (M. avium (13%), M. intracellulare (10%)), M. gordonae (14%), and M. fortuitum (12%). The ratio of isolation of NTM to M. tuberculosis in all hospitalized patients was 0.59. CONCLUSIONS: The first data on the epidemiology of pulmonary NTM in Athens, Greece, are presented. NTM infection is common in patients with chronic respiratory disease. However, only a significantly smaller proportion of patients fulfill the criteria for NTM disease.

A case of tracheal hamartoma resected with loop electrocautery.

The authors report on the case of a 67-year-old man with longstanding breathlessness, which was eventually attributed to a fixed mass in the upper third of the trachea causing upper airway obstruction. The lesion was amenable to loop electrocautery resection via flexible bronchoscopy that led to prompt resolution of patient symptoms. Biopsy was consistent with tracheal hamartoma, an exceedingly rare benign tracheal tumor. All the cases of tracheal hamartomas in the literature to date, the application of electrocautery and other methods of interventional bronchoscopy for resection of selected tracheal tumors are discussed.