FEV1 Variability Predicts Lung Transplant or Mortality in Cystic Fibrosis Patients in the US.

RATIONALE: Declines in percent predicted Forced Expiratory Volume in 1 Second (ppFEV1) are an important marker of clinical progression of Cystic Fibrosis (CF). OBJECTIVES: We examined ppFEV1 variability on a combined outcome of lung transplant or death. METHODS: We estimated the association between ppFEV1 variability and the combined outcome of lung transplant or death. We included children ages 8 years and above with CF and two prior years of ppFEV1 data before baseline between 2005 and 2021. We defined ppFEV1 increased variability as any relative increase or decrease of at least 10% in ppFEV1 from a two-year averaged baseline. A marginal structural Cox proportional hazards model was used. We examined a cumulative measure of ppFEV1 variability, defined as the cumulative proportion of visits with ppFEV1 variability at each visit. Kaplan-Meier survival curves were generated based upon quartiles of the cumulative distribution of ppFEV1 variability. MEASUREMENTS AND MAIN RESULTS: We included 9,706 CF patients in our cohort. Median age at cohort entry was 8.3 (IQR 8.2 - 8.4) years, 50% of patients were female, 94% white, and median baseline ppFEV1 was 94.4 (IQR 81.6 - 106.1). The unadjusted HR for increased ppFEV1 variability on lung transplant/mortality was 4.13 (95% CI 3.48 - 4.90) and the weighted HR was 1.49 (95% CI 1.19 - 1.86). Survival curves stratified by quartile of cumulative variability demonstrated an increased hazard of lung transplant/mortality as the proportion of cumulative ppFEV1 variability increased. CONCLUSIONS: We found a strong association between ppFEV1 variability and lung transplant or mortality in a cohort of people with CF in the US.

Interventional Procedures in Patients With Pulmonary Vascular Obstruction.

A 21-year-old patient presented with a short history of fatigue and dyspnea on a background of double-lung transplantation for cystic fibrosis and preexisting chronic superior vena cava obstruction. Computed tomography of the chest demonstrated a 3-cm mass occluding the right pulmonary veins, with associated right upper and lower lobe pulmonary parenchymal infiltrates. Two invasive procedures were performed, with similar complications in both procedures.

Diagnostic performance of endobronchial ultrasound-guided mediastinal lymph node sampling in early stage non-small cell lung cancer: A prospective study.

BACKGROUND AND OBJECTIVE: Standard nodal staging of lung cancer consists of positron emission tomography/computed tomography (PET/CT), followed by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) if PET/CT shows mediastinal lymphadenopathy. Sensitivity of EBUS-TBNA in patients with N0/N1 disease by PET/CT is unclear and largely based on retrospective studies. We assessed the sensitivity of EBUS-TBNA in this setting. METHODS: We enrolled patients with proven or suspected lung cancer staged as N0/N1 by PET/CT and without metastatic disease (M0), who underwent staging EBUS-TBNA. Primary outcome was sensitivity of EBUS-TBNA compared with a composite reference standard of surgical stage or EBUS-TBNA stage if EBUS demonstrated N2/N3 disease. RESULTS: Seventy-five patients were included in the analysis. Mean tumour size was 3.52 cm (±1.63). Fifteen of 75 patients (20%) had N2 disease. EBUS-TBNA identified six while nine were only identified at surgery. Sensitivity of EBUS-TBNA for N2 disease was 40% (95% CI: 16.3-67.7%). CONCLUSION: A significant proportion of patients with N0/N1 disease by PET/CT had N2 disease (20%) and EBUS-TBNA identified a substantial fraction of these patients, thus improving diagnostic accuracy compared with PET/CT alone. Sensitivity of EBUS-TBNA however appears lower compared with historical data from patients with larger volume mediastinal disease. Therefore, strategies to improve EBUS-TBNA accuracy in this population should be further explored.

A Prediction Model to Help with the Assessment of Adenopathy in Lung Cancer: HAL.

RATIONALE: Estimating the probability of finding N2 or N3 (prN2/3) malignant nodal disease on endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in patients with non-small cell lung cancer (NSCLC) can facilitate the selection of subsequent management strategies. OBJECTIVES: To develop a clinical prediction model for estimating the prN2/3. METHODS: We used the AQuIRE (American College of Chest Physicians Quality Improvement Registry, Evaluation, and Education) registry to identify patients with NSCLC with clinical radiographic stage T1-3, N0-3, M0 disease that had EBUS-TBNA for staging. The dependent variable was the presence of N2 or N3 disease (vs. N0 or N1) as assessed by EBUS-TBNA. Univariate followed by multivariable logistic regression analysis was used to develop a parsimonious clinical prediction model to estimate prN2/3. External validation was performed using data from three other hospitals. MEASUREMENTS AND MAIN RESULTS: The model derivation cohort (n = 633) had a 25% prevalence of malignant N2 or N3 disease. Younger age, central location, adenocarcinoma histology, and higher positron emission tomography-computed tomography N stage were associated with a higher prN2/3. Area under the receiver operating characteristic curve was 0.85 (95% confidence interval, 0.82-0.89), model fit was acceptable (Hosmer-Lemeshow, P = 0.62; Brier score, 0.125). We externally validated the model in 722 patients. Area under the receiver operating characteristic curve was 0.88 (95% confidence interval, 0.85-0.90). Calibration using the general calibration model method resulted in acceptable goodness of fit (Hosmer-Lemeshow test, P = 0.54; Brier score, 0.132). CONCLUSIONS: Our prediction rule can be used to estimate prN2/3 in patients with NSCLC. The model has the potential to facilitate clinical decision making in the staging of NSCLC.

Biomarkers to identify ILD and predict lung function decline in scleroderma lung disease or idiopathic pulmonary fibrosis.

BACKGROUND: SSc-ILD and IPF demonstrate significant morbidity and mortality. Predicting disease progression is challenging in both diseases. OBJECTIVES: We sought a serum biomarker that could identify patients with SSc-ILD or IPF and prospectively predict short-term decline in lung function in these patients. METHODS: 10 healthy controls, 5 SSc w/o ILD, 6 SSc-ILD and 13 IPF patients underwent venesection. An array of cytokines including KL-6, SP-D and MMP7 were measured. PFTs were obtained at baseline and six months. Cytokine measurements were correlated with PFTs. RESULTS: KL-6 in IPF patients (633 ng/ml, IQR 492-1675) was significantly elevated compared to controls (198 ng/ml, IQR 52-360, p<0.01) and SSc w/o ILD patients (192 ng/ml, IQR 0-524, p<0.05); KL-6 in SSc-ILD patients (836 ng/ml, IQR 431-1303) was significantly higher than in controls (p<0.05). SP-D was significantly higher in IPF patients (542 ng/ml, IQR 305-577) compared to controls (137 ng/ml, IQR 97-284, p<0.01) or to SSc w/o ILD patients (169 ng/ml, IQR 137-219, p<0.05). In comparison with controls (0.0 ng/ml, IQR 0.0-0.6), MMP7 was significantly higher in both IPF patients (2.85 ng/ml, IQR 1.5-3.6, p<0.05) and SSc-ILD patients (5.41 ng/ml, IQR 2.6-7.2, p<0.001). Using a cut-off level of 459ng/ml for KL-6 and of 1.28 ng/ml for MMP7, 18 out of 19 patients with ILD had a serum value of either KL-6 or MMP7 above these thresholds. For all ILD patients, baseline serum SP-D correlated with ΔFVC %pred over six months (r=-0.63, p=0.005, 95% CI -0.85 to -0.24). CONCLUSIONS: Combining KL-6 with MMP7 may be a useful screening tool for patients at risk of ILD. SP-D may predict short-term decline in lung function.

Microbiota and metabolite profiling reveal specific alterations in bacterial community structure and environment in the cystic fibrosis airway during exacerbation.

Chronic polymicrobial infections of the lung are the foremost cause of morbidity and mortality in cystic fibrosis (CF) patients. The composition of the microbial flora of the airway alters considerably during infection, particularly during patient exacerbation. An understanding of which organisms are growing, their environment and their behaviour in the airway is of importance for designing antibiotic treatment regimes and for patient prognosis. To this end, we have analysed sputum samples taken from separate cohorts of CF and non-CF subjects for metabolites and in parallel, and we have examined both isolated DNA and RNA for the presence of 16S rRNA genes and transcripts by high-throughput sequencing of amplicon or cDNA libraries. This analysis revealed that although the population size of all dominant orders of bacteria as measured by DNA- and RNA- based methods are similar, greater discrepancies are seen with less prevalent organisms, some of which we associated with CF for the first time. Additionally, we identified a strong relationship between the abundance of specific anaerobes and fluctuations in several metabolites including lactate and putrescine during patient exacerbation. This study has hence identified organisms whose occurrence within the CF microbiome has been hitherto unreported and has revealed potential metabolic biomarkers for exacerbation.

Bacterial cis-2-unsaturated fatty acids found in the cystic fibrosis airway modulate virulence and persistence of Pseudomonas aeruginosa.

There is an increasing appreciation of the polymicrobial nature of many bacterial infections such as those associated with cystic fibrosis (CF) and of the potentially important role for interspecies interactions in influencing both bacterial virulence and response to therapy. Patients with CF are often co-infected with Pseudomonas aeruginosa and other pathogens including Burkholderia cenocepacia and Stenotrophomonas maltophilia. These latter bacteria produce signal molecules of the diffusible signal factor (DSF) family, which are cis-2-unsaturated fatty acids. We have previously shown by in vitro studies that DSF from S. maltophilia leads to altered biofilm formation and increased resistance to antibiotics by P. aeruginosa; these responses of P. aeruginosa require the sensor kinase PA1396. Here we show that DSF signals are present in sputum taken from patients with CF. Presence of these DSF signals was correlated with patient colonization by S. maltophilia and/or B. cenocepacia. Analysis of 50 clinical isolates of P. aeruginosa showed that each responded to the presence of synthetic DSF by increased antibiotic resistance and these strains demonstrated little sequence variation in the PA1396 gene. In animal experiments using CF transmembrane conductance regulator knockout mice, the presence of DSF promoted P. aeruginosa persistence. Furthermore, antibiotic resistance of P. aeruginosa biofilms grown on human airway epithelial cells was enhanced in the presence of DSF. Taken together, these data provide substantial evidence that interspecies DSF-mediated bacterial interactions occur in the CF lung and may influence the efficacy of antibiotic treatment, particularly for chronic infections involving persistence of bacteria.

Radiologic imaging in cystic fibrosis: cumulative effective dose and changing trends over 2 decades.

OBJECTIVE: With the increasing life expectancy for patients with cystic fibrosis (CF), and a known predisposition to certain cancers, cumulative radiation exposure from radiologic imaging is of increasing significance. This study explores the estimated cumulative effective radiation dose over a 17-year period from radiologic procedures and changing trends of imaging modalities over this period. METHODS: Estimated cumulative effective dose (CED) from all thoracic and extrathoracic imaging modalities and interventional radiology procedures for both adult and pediatric patients with CF, exclusively attending a nationally designated CF center between 1992-2009 for > 1 year, was determined. The study period was divided into three equal tertiles, and estimated CED attributable to all radiologic procedures was estimated for each tertile. RESULTS: Two hundred thirty patients met inclusion criteria (2,240 person-years of follow-up; 5,596 radiologic procedures). CED was > 75 mSv for one patient (0.43%), 36 patients (15.6%) had a CED between 20 and 75 mSv, 56 patients (24.3%) had a CED between 5 and 20 mSv, and in 138 patients (60%) the CED was estimated to be between 0 and 5 mSv over the study period. The mean annual CED per patient increased consecutively from 0.39 mSv/y to 0.47 mSv/y to 1.67 mSv/y over the tertiles one to three of the study period, respectively (P < .001). Thoracic imaging accounted for 46.9% of the total CED and abdominopelvic imaging accounted for 42.9% of the CED, respectively. There was an associated 5.9-fold increase in the use of all CT scanning per patient (P < .001). CONCLUSIONS: This study highlights the increasing exposure to ionizing radiation to patients with CF as a result of diagnostic imaging, primarily attributable to CT scanning. Increased awareness of CED and strategies to reduce this exposure are needed.

Idiopathic pulmonary fibrosis: treatment update.

Idiopathic pulmonary fibrosis (IPF) is the most common of the idiopathic interstitial pneumonias. Despite multiple recent clinical trials, there is no strong evidence supporting a survival advantage for any agent in the management of patients with IPF. The limited effectiveness of current treatment regimes has led to a search for novel therapies including antifibrotic strategies. This article reviews the evidence supporting the treatments currently used in the management of IPF.

Nebulized hypertonic saline via positive expiratory pressure versus via jet nebulizer in patients with severe cystic fibrosis.

BACKGROUND: Nebulized hypertonic saline is a highly effective therapy for patients with cystic fibrosis (CF), yet 10% of patients are intolerant of hypertonic saline administered via jet nebulizer. Positive expiratory pressure (PEP) nebulizers splint open the airways and offers a more controlled rate of nebulization. METHODS: In 4 consecutive adult CF patients who were intolerant of hypertonic saline via jet nebulizer, we nebulized 6% hypertonic saline via a PEP nebulizer. We measured the number of days the patients required intravenous antibiotics from enrollment to study end, compared to an equal period before PEP, and the mean time between the patients' 3 most recent infective pulmonary exacerbation episodes before PEP to their next exacerbation after PEP. Patients also completed a Likert-scale adverse-effects questionnaire on hypertonic saline via PEP versus jet nebulizer. RESULTS: The 4 patients had severe CF pulmonary disease and all fully tolerated hypertonic saline via PEP, for 77, 92, 128, and 137 days, respectively until the study end date. There were fewer days of antibiotics in 3 of the 4 patients, from 45 to 20 days, 66 to 14 days, and 28 to 0 days (mean relative risk reduction 53%, P = .11). The other patient had 63 days of antibiotics during both the PEP and the jet nebulizer periods. There was a mean 3.6-fold longer time to next infective pulmonary exacerbation during the PEP period (P = .07). Adverse effects were less with PEP: chest tightness 68% (P = .04), bad taste 62% (P = .06), cough 47% (P = .10), and sore throat 50% (P = .20). CONCLUSIONS: Hypertonic saline via PEP nebulizer benefits CF patients who do not tolerate hypertonic saline via jet nebulizer.